LEGEND project, Pre-investment analysis (GeoZS)

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The project is co-funded by the European Union Instrument for Pre-Accesion Assistance

LEGEND PROJECT

Pre-investment analysis for large Ground Source Heat Pump investments in Obalno-kraška region

Project partner Geological Survey of Slovenia Dimičeva ulica 14 1000 Ljubljana Slovenia www.geo-zs.si


LEGEND PROJECT


Name of the action

Pre-investment analysis for large GSHP investments in Obalno-kraška (Coastal-Karst) region (Slovenia)

AF Reference

4.3 a – Elaboration of pre-investments

Leader of the action

Province of Ferrara

Responsible

Francesco Tinti Contacts: E-mail: francesco.tinti@unibo.it Ph Num: +39 0512090477 Cell: +39 3358239415

Institution name

Geological Survey of Slovenia (GeoZS)

Address (street, number, postal code, City, Country)

Dimičeva ulica 14, SI - 1000 Ljubljana, Slovenia

Contact data (Ph Num, Fax, E-mail, website)

Ph Num: 386-1-2809-700 Fax: 386-1-2809-753 E-mail: www@geo-zs.si Website: http://www.geo-zs.si

Prepared by: Joerg Prestor Simona Pestotnik Dušan Rajver

September 2014

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Content 1. Executive summary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 1. 1. Introductory explanations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 1. 2. Executive summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 1. 2. 1. Subject of the analysis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 1. 2. 2. Concerned variants. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7 1. 2. 3. Investment value. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 1. 2. 4. Timetable. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 1. 2. 5. Sources of financing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 1. 3. Basic information about the investor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 1. 4. Objectives or strategy goals. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 2. Analysis of the present situation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 2. 1. Analysis of the present situation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 2. 2. The existing and anticipated needs for investment (trends of demand) in the area of heating and cooling sector. . . . . . . . 11 2. 2. 1. Boundary conditions from Local energy concepts of municipalities. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 2. 2. 2. Forecast of expected shares of RES for the heating and cooling of public buildings in the municipality of Piran. . . 15 2. 3. Consistency of the investment project with the development strategy of Slovenia, EU guidelines, spatial planning documents and other long-term development programmes and policies, by also taking into account the consistency of policy areas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 3. An analysis of market opportunities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 3. 1. An analysis of the business environment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 3. 1. 1. The potential of shallow geothermal energy in the Obalno-kraška (Coastal-Karst) region. . . . . . . . . . . . . . . . . . . . . . . 21 3. 1. 2. Rapid estimation of geothermal potential on the site of the building. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 3. 2. Review of climatic and geological data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 3. 3. Review of energy data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 3. 3. 1. Critical review of existing energy audit of selected building. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 3. 4. An analysis of the existing prices. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 3. 5. SWOT analysis with setting targets. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 4. Analysis of the options with an estimation of project costs and benefits and efficiency calculations for the economic useful life of the investment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 4. 1. Modelling of energy needs for delivered energy to the building and preparation of proposal for investment. . . . . . . . . . . . . 35 4. 2. Geothermal input data for modelling the abstraction (intake) of shallow geothermal energy . . . . . . . . . . . . . . . . . . . . . . . . . . 40 4. 3. BHE modelling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44 4. 4. Benefit assessment for proposed solutions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49 4. 5. Project efficiency for the economic useful life of the investment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50

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5. Impact analysis with a description of the major impacts of the investment from the environmental acceptability perspective. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52 5. 1. Environmental impact analysis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52 5. 2. Efficient use of space, in accordance with the needs of regional development and sustainable development of the society. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52 6. Human resources’ analysis by individual options and an analysis of the impact on employment from the economic and social structure perspectives. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53 7. An indicative timetable for implementing the investment with investment dynamics by option. . . . . . . . . . . . . . . . . . . . . . . 55 8. An indicative financing structure for each option, including the obligatory analysis of the reasonability of using publicprivate partnership concept . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56 9. A calculation of financial and economic indicators. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57 9. 1. Investment from a perspective of financial and economic indicators. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57 9. 2. A specification of the costs and benefits that cannot be evaluated in terms of money. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59 10. A risk analysis and a sensitivity analysis for each option. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60 11. Presentation of the appraisal criteria and weights for the selection of the optimum variant. . . . . . . . . . . . . . . . . . . . . . . . . 61 12. A comparison of the options with a proposal and a justification of the choice of the best option (optimum variant). . . . . 62 13. Annexes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63 Annex 1: Energy consumption assessments – heating, hot water and electricity, actual energy use and expenses. . . . . . . . . . 63 Annex 2: Case studies selected as BPs and their main features.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64 Annex 3: Ground Source Heat Pumps demonstration cases in public and residential buildings utilizing GSHP in the Adriatic area.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66 Annex 4: Locations of sewer pipes, water supply network, gas network, heat energy network.. . . . . . . . . . . . . . . . . . . . . . . . . . . . 75 Annex 5: Working diagrams for selected GCHPs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77

This report has been produced with the financial assistance of the IPA Adriatic Cross-Border Cooperation Programme. The contents of this report are the sole responsibility of Geological Survey of Slovenia and can under no circumstances be regarded as reflecting the position of the IPA Adriatic Cross-Border Cooperation Programme Authorities.

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1. Executive summary 1. 1. Introductory explanations The present report has been prepared within the framework of the project LEGEND “Low Enthalpy Geothermal Energy Demonstration cases for Energy Efficient building in Adriatic area” (IPA Adriatic Cross-Border Cooperation Programme). The overall objective of the LEGEND project is the promotion of energy efficiency concepts and the low-enthalpy geothermal energy benefits in the Adriatic area. The pre-investment analysis provide information about the cost/benefit for the introduction of massive ground source heat pump investments in highly populated and CO2 high emission areas (old and new buildings fund) fitting with the local energy concepts. The target area is the densely populated coastal area in Obalno-kraška region (Slovenia) where there are favourable natural conditions (flysch and clayey layers) for ground source heat pump (GSHP) implementations. The pre-investment analysis has been prepared in line with Decree on the uniform methodology for the preparation and treatment of investment documentation in the field of public finance (OG RS, 60/2006, 54/2010)1. It determines a uniform methodology for the preparation and treatment of investment documents in the field of public finance. The pre-investment analysis was demonstrated on the basis of real data and the intended refurbishment of existing public building - the kindergarten Morje in the municipality of Piran – selected as a demonstration building. The elaboration follows the required chapters in two parts. In the first part there are key analyses of the: • present situation and the existing and anticipated needs for investment, • market opportunities, • options for the economic useful life of the investment, • major impacts of the investment, • human resources. The second part of the elaborate summarizes the results of the preceding analysis and presents the: • indicative timetable of the investment, • indicative financing structure, • calculation of financial and economic indicators, • risk and sensitivity assessment, • criteria and weights for the selection of the optimum variant, • justification of the choice of the optimum variant. The task of the pre-investment analysis is to examine the possible project solutions and from a plurality - three selected possible variants present it to the contracting entity. These three variants enable the contracting entity for detailed examination in the feasibility study. The inventory of energy consumption of the kindergarten Morje, thermographic analysis, microclimatic measurements, 3D dynamic model of thermal response of building elements and estimation of heat rating of the building were performed by external expert for building physics (by the aid of IDA IC v4.6 software). In order to assure replicability of such a system in the entire Obalno-kraška region the kindergarten Morje was placed in 3 different (hydro)-geological conditions (flysch / karst / alluvial gravel) and 2 different climate conditions (continental and coastal climate). The heat extraction rates and the costs of borehole heat exchanger (BHE) field were calculated using the Earth Energy Designer 3.0 software. A dynamic long-term development of fluid temperature was calculated using the numerical model FeFlow 6.2. For comparison of annual costs for different energy systems we used the calculation spreadsheet adapted after Swiss Heat Pump Association. The economic viability of the investments was assessed following the Swiss Standard SIA 480. 1 http://www.pisrs.si/Pis.web/pregledPredpisa?id=URED3708 (art.:12).

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1. 2. Executive summary 1. 2. 1. Subject of the analysis The subject of the pre-investment analysis was to demonstrate how to include and present shallow geothermal energy as one of the most effective and environmental-friendly heating and cooling technology for public buildings in Obalno-kraška region. Public bodies can play an important role in promoting investments in renewable sources of energy and encouraging best practice in their buildings. This was the main reason for the selection of an old public building. The main motivation for the investments in energy efficiency and renewable energy sources are lower energy bills, primary energy savings and enhanced thermal comfort. Energy efficient renovation provides also health benefits – reducing cold related illnesses. The latter shall be necessary to consider in buildings such as schools and kindergartens. On the basis of that one of the kindergartens in Obalno-kraška region was selected for pre-investment analysis. Energy performance certificates categorize buildings from ‘A’ to ‘G’ where ‘A’ is the most efficient category. Local energy concepts of municipalities in Obalno-kraška region show that public schools and kindergartens are dominantly using oil and gas, non-renewable energy sources. They are mainly energy efficient rating performing buildings (‘D’ rating). The selected building for pre-investment analysis - kindergarten Morje - has ‘F’ grade and is classified as wasteful type of building. The territory of the analysis was Obalno-kraška region with favourable natural conditions (flysch and clayey layers) for ground source heat pumps (GSHP) implementations in particular for closed loop systems (ground coupled heat pump - GCHP). In preinvestment analysis for the case study of kindergarten Morje a closed loop system with six boreholes, each 147.5 meters deep and layout in a U-shape has been chosen.

1. 2. 2. Concerned variants For energy efficient reconstruction of kindergarten Morje four possible variants have been considered. Baseline variant is the existing situation – conventional energy sources (LPG heat plant), with heat requirement 161 MWh/a. Option 1 variant is replacement of heating system with ground coupled heat pumps and installation of mechanical ventilation with heat recovery and energy consumption 148 MWh/a, of which at least ¾ is renewable. Option 2 variant is renovation of the building envelope - external wall, windows, roof, leaving 101 MWh/a of energy demand. Option 3 variant is replacement of heating system with ground coupled heat pumps, renovation of the building envelope and installation of mechanical ventilation with heat recovery) with lowest heat requirements 97 MWh/a. Calculated financial indicators show in favour to option 1 (net present value 279,402 EUR, internal rate of return 11.2 % and payback period 9 years). The most unfavourable financial indicators are in option 2 (net present value -57,693 EUR, internal rate of return 3.5 % and payback period 19 years). Environmental indicators, reduction of CO2 emission and reduction of primary energy show in favour to option 3 (emission CO2 -28.77 t/a, primary energy -149.57), followed by option 2 (emission CO2 -18.45 t/a, primary energy -92.17) and option 3 (emission CO2 -9.88 t/a, primary energy -60.43). In order to assure replicability of such a system in the entire Obalno-kraška region the kindergarten Morje was placed in 3 different (hydro)-geological conditions (flysch / karst / alluvial gravel) and 2 different climate conditions (continental and coastal climate). For selected building, which is situated in the coastal climate, there is 60 % less energy demands for space heating and 40% more energy demands for space cooling in comparison to the same building situated in the continental climate. For the assessment of the heat extraction rate of borehole heat exchangers (BHEs) under different (hydro)-geological and climate conditions the numerical model Fe-Flow 6.2 was used. The heat extraction rates were compared and calibrated with results of the analytical model Earth Energy Designer (EED) 3.0. The results show that groundwater flow has significant positive influence on the performance of BHEs. The thermal conductivities, volumetric heat capacities, porosities of materials make a lower impact on the heat extraction rates. The differences between the analytical and numerical results are likely accounted for discrepancies between the considered flow conditions. The EED model does not consider groundwater flow.

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1. 2. 3. Investment value For comparison of the annual costs for different energy systems two different models for comparison of the annual costs for different energy systems were prepared. The first model was adapted after existing Swiss Heat Pump Association model. The calculation was made for the following energy sources: natural gas, heating oil, liquefied petroleum gas (LPG), ground source heat pump, air source heat pump and pellets. For calculation of viability the following factors were taken into consideration: total annual energy consumption for heating, total costs of investment in heating plant and system (without subsidies), energy costs and other energy costs such as service and repair costs, costs of sources of financing, taxes on energy etc. The results of comparison of annual costs have shown that ground source heat pumps are the cheapest option for heating of the kindergarten Morje while the LPG is the most expensive option. The initial investment costs are highest for ground source heat pump system and make up 47 % of annual costs. The lowest costs of the initial investment are for heating oil system which is 4 % of annual costs. Energy costs are highest for LPG (88 % of annual costs) and lowest for ground source heat pumps (48 % of annual costs). Other energy costs are highest for pellets system (5 % of annual costs) and lowest for ground source heat pumps (1 % of annual costs). Taxes on energy are highest for heating oil system (14 % of annual costs) and lowest for pellets system (0 % of annual costs). The second model was adapted after Swiss Standard SIA 480 for economic viability calculation for investment. The results of the calculation are presented in form of following indicators: capital appreciation, investment output (return), payback time, annual net income and cost price for unit of exploitation. The selection of one or more indicators is carried out depending on the specific questions to which the viability calculation must answer. Abovementioned indicators were calculated for case study of the kindergarten Morje, Option 1 as follows: capital appreciation 242,161 EUR, investment output 11.17 %, payback time 9 years, annual net income 10,372 EUR/a and cost price for unit of exploitation 0.09 EUR/kWh. We assume that in a given case in feasibility study it is necessary to examine the possibility of implementation of Option 1_HCD. If we consider that the lifetime of BHE is at least 30 years, in the meantime we can expect that the savings might be invested in new building envelope. The savings at the cost of savings from Option1_HCD can be invested in new building envelope from Option 1 already after 17 years of operating the ground coupled heat system. By that the need for delivered and consumed energy would be lower and heat pump with capacity of 55 kW would be adequate. In consequence, afterwards the BHE will be significantly more energy efficient (higher SPF) and cost effective. The energy costs for heating and cooling would be in that case more than 4-times less than the present-day (Table 25).

1. 2. 4. Timetable Procedures for thermo technical system elaboration, geological investigation, implementation design, authorization procedures (except for closed loop systems with boreholes up to 300 m, which are not situated in aquifers, protected areas and areas under threat, or where deposits of coal or hydrocarbons are located), installations of boreholes, installations of thermo technical system (heat pumps) and installations of monitoring system takes about 1 year. For public sector a public tender procedure is obligatory for any proceedings which can cause delays.

1. 2. 5. Sources of financing There are many more financial measures available to promote renewable energy sources and energy efficiency to households, private and public sector. The Ecological Fund of the Republic of Slovenia (RS) has loans and subsidies: low interest loans for companies, households and municipalities (3 month Euribor + 1.5 %). Ecological Fund provides also non-refundable subsidies for households (25 % of the total and not more than 2,500 EUR). Slovenian Regional Development fund has favourable loans for municipalities, entrepreneurs and companies and agricultural holdings (3 month Euribor + 0.80 % + 2.50 % (based on development indicator for municipality)). SID Bank provides favourable loans for municipalities and for small and medium enterprises (conditions determined on a case-by-case basis). There are funds available from European Cohesion Policy for private and public sector (co-financing part shall not exceed 85 %) and national co-financing (Ministry of Economic Development and Technology). Also public-private finance business models are more and more frequent.

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1. 3. Basic information about the investor The investor in our case is the municipality of Piran. Presentation of the municipality of Piran: Investor:

municipality Piran

Address:

Fazanska ulica 3, 6320 Portorož, Slovenia

Phone:

+386 (0) 5 6710-326

Contact person:

Mr. Boris Kočevar

Area:

45 km2 (SURS, 2011)

Number of settlements:

15 (SURS, 2011)

Population:

17,687 (SURS, 2011)

Number of dwellings:

10,694 (SURS, 2011)

Density of population:

397/km2 (SURS, 2011)

Figure 1. Geographical location of the Municipality of Piran in Slovenian space.

1. 4. Objectives or strategy goals With investment in energy efficiency and renewable energy sources in buildings the following objectives will be reached: • Reduce energy costs; • Increase energy security; • Enhanced comfort and improved health; • Expanding markets for ground source heat pumps technologies worldwide; • Develop skills and supply chains. The mentioned objectives will be achieved with following actions: • Replacement of heating system with vertical ground coupled heat pumps (GCHPs) and installation of mechanical ventilation with heat recovery. After nine years, when the investment will be refunded, through savings; • Option 2: Renovation of the building envelope (PURES 2,2010); • Option 3: Replacement of heating system with vertical GCHPs, *renovation of the building envelope (PURES 2, 2010) and installation of mechanical ventilation with heat recovery.

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2. Analysis of the present situation 2. 1. Analysis of the present situation In the Adriatic region where the EU program IPA Adriatic runs, Slovenia has three regions, namely Obalno-kraška, Notranjskokraška and Goriška region. Within the LEGEND project we had focused on the Obalno-kraška region. A characteristic of this region is that it comprises the Adriatic coast and has a typical Mediterranean climate. Due to the warmer climate the buildings in the coastal zone have approximately 30 – 40 % less heating demands as buildings in the continental part. On the other hand, this area is also characterized by greater heat surpluses and greater cooling needs. In addition, the Obalno-kraška region has some other characteristics that are typical for many regions of the Adriatic coast: the specific geological structure of the territory. The flysch and carbonate rocks strongly predominate, consisting by mostly marl, sandstone and limestone. Along the coast there is relatively little flat land, and then the surface quickly enlivens and turns to the hills in the hinterland in exceeding 1000 m above sea level. Along the coast in the surroundings of Portorož, the climate is so warm that the mean air temperatures during the heating season achieve around 8 °C; external project temperature is -4 °C. To that end the air source heat pumps are much more efficient in the coastal area than in the continental area. However, the ground source heat pumps are more efficient due the higher temperature of the soil at the surface. Geothermal heat pumps most effectively exploit the energy of the Sun. The buildings represent, together with transport and industry, one of the key sectors in the strategy of energy saving and reducing the greenhouse gas emissions. As an important part of the building stock is in the public domain, the public buildings may be considered as an example of good practice and therefore the public administrations should be forefront in the investments in resources to achieve at least the minimum energy efficiency and use of renewable energy sources. Public buildings have without a doubt the major role in promoting investments in renewable energy sources, because the public can follow what the actual return on investment is. At the same time they are mainly larger consumers where it is possible to introduce advanced technology and the latest knowledge. For an example of the integration of shallow geothermal energy in the pre-investment analysis, we therefore chose between public buildings. The Register of buildings includes more different data and information on buildings, such as use, year of construction, renovations, installations, etc. Besides, if we look only public buildings, they are very different. These are, for example, sheltered housing, commercial premises of public administration, stations, fire halls, halls for social events, libraries, schools, kindergartens, facilities for education, health care facilities, prisons, barracks, and so on. Only in the area of the Obalno-kraška region there is 1,424 different parts of public buildings at 888 locations. Of these, 23 different types of land use, which is particularly important for the project due to various internal temperature during heating and cooling season. Therefore the kindergartens have internal temperature up to 24 °C at the time of heating, a bus station or a hall, for example, only 18 °C. Buildings with lower project inlet temperatures are of particular interest for heating with shallow geothermal energy. This applies even more if geothermal energy can be directly exploited (without heat pump). The selection of most appropriate public building was made in compliance with the following criteria: • an existing public building; • renewable technology for heating have not yet been installed in the building; • greater distance from existing gas transmission network; • minor accessibility of biomass; • building with higher required heating power > 30 kW; • a large number of available data on energy consumption and building physics; • building is in the plan for renovation or replacing of heating system; • building has also energy needs for cooling; • building has lower standards for indoor temperature ~ 20 °C (eg. stations or other public places); • building has limited spatial options for the installation of larger boilers, storage tanks… Based on these criteria (with the exception of point 9) and principally, of course, depending on the willingness of representatives of the municipality to cooperate we chose a kindergarten VVZ Morje in Lucija.

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LEGEND PROJECT


2. 2. The existing and anticipated needs for investment (trends of demand) in the area of heating and cooling sector The main motivation for the investments in energy efficiency and renewable energy sources are lower energy bills, primary energy savings and enhanced thermal comfort. Energy efficient renovation provides also health benefits – reducing cold related illnesses. The latter is particularly important in those public buildings such as schools and kindergartens. Other important factor is statutory requirement. In cases of major renovations (renovation of at least 25 % of the surface of the building envelope) beside investment to improve energy efficiency there is also required investment in renewable energy source (PURES 2, 2010). Important stimuli for such investments are also financial incentives. The analysis of existing and anticipated needs for investments in shallow geothermal energy in the area of heating and cooling sector in Obalno-kraška region was made on the basis of the review of the Local energy concepts (LEC) and Spatial planning documents for seven municipalities in Obalno-kraška region.

2. 2. 1. Boundary conditions from Local energy concepts of municipalities It is important that the public is informed about the annual shares of renewable energy sources in the energy mix, as well as the energy shares from geothermal heat pumps. These contributions should be published or freely available for public. Ideally, it should be presented together with the objectives of National renewable energy action plan (NREAP) and with the objectives of individual municipalities (LEC). The lead role in the implementation of this can have signatories of the Covenant of Mayors. The goals must come from local level, it is therefore essential that this information is presented to the public in local communities. From the LEC of the municipality of Divača it is clearly visible, that the planned growth of total contribution from shallow geothermal energy is approximately 24 MWh per year and by 2020 an overall increase of 210 MWh. About two smaller buildings per year or two bigger buildings within ten years are meant. Table 1. Local energy concept of the municipality Divača: RES technology for heating and cooling – estimated total contribution to the binding targets for 2020 and indicative shares for 2010-2020 (GOLEA, 2011). Values in MWh

Year LEC

2010

2012

2014

2016

2018

2020

Renewable energy through heat pumps:

400

454

508

562

616

670

800

Aerothermal

250

280

310

340

370

400

440

Geothermal

150

174

198

222

246

270

360

Hydrothermal

0

0

0

0

0

0

0

On the basis of Energy act the municipalities must accept the Local energy concepts (LEC). LEC is an important tool in planning strategy of municipal energy policy (an analysis of existing situation of energy use and energy supply, a proposals relating to the measures to be taken to maximizing energy efficiency). Energy policy of the municipality should follow the National energy program and energy policy of the Republic of Slovenia and EU. On this basis is possible an overview of energy use and energy products for heating and cooling in entire Slovenia. At the same time the overview of the potential of renewable energy sources could be developing. Within this the active role of local communities on policies of energy supply in the future is based. All of this is aimed to increase energy efficiency and independence. In the Local energy concepts data (in some more detailed as elsewhere) are given from simple energy audits of public buildings and proposed measures for individual public buildings. This is a base for future orientations of energy measures at the national level, for example, for Operational programmes or for National renewable energy action plan. This logically means the realization of particular interests of local communities. Based on the Local energy concepts (LEC) of the municipalities in the Obalno-kraška region, we have provided a conclusions concerning energy supply for heating and cooling and utilisation of shallow geothermal energy. In Obalno-kraška region seven municipalities exist: Komen, Piran, Sežana, Koper, Hrpelje–Kozina, Izola and Divača (Figure 2), and all have adopted the LECs.

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Figure 2. Municipalities in the Obalno-kraška region. From LECs we can conclude that the most commonly used source for heating in households are wood or heating oil; in public buildings this is liquefied petroleum gas or heating oil; and in industry are electricity, heating oil and small amounts of wood. Weaknesses of energy supply in the municipalities are similar to each other. The greatest problems are decrepit windows and doors, poor insulation, no thermostatic radiator valves, old roof covering, etc. The renewable energy potential is the highest for exploitation of solar and wind energy. In the municipalities Komen, Sežana, Hrpelje-Kozina and Divača a very high biomass potential exists. As provided in LECs the potential of geothermal energy in the Obalno-kraška region has not been sufficiently studied. As stated in the LEC of the municipality of Hrpelje - Kozina, there is some potential for use of shallow geothermal energy, in terms of GCHPs for heating and cooling purposes. Based on LEC of the municipality of Divača there is no exploitation of geothermal energy. In the municipality of Komen a plan exists to conduct one heat pump in a public building. In the municipality of Piran they intend to use hydrothermal heat pumps by which they will have heat from the sea exploited for heating and cooling of individual buildings in Piran. In LEC of Sežana stays that the potential of geothermal energy in municipality is difficult to be predict. At the municipality of Koper as provided in LEC the potential of geothermal energy has not been sufficiently studied. In the municipality of Izola there is an estimate that the potential for exploitation of geothermal energy, but it has to be explored and proven as economical to use. Measures to support geothermal energy are not provided. On the territory of the municipalities of Hrpelje–Kozina, Koper, Izola and Piran a plan exists for construction of a natural gas transmission system M6 Ajdovščina – Lucija. On the territories fitted with distribution or district heating systems the connection on this system is obligatory with the exception of those, which more than two-thirds of heating needs cover with renewable energy sources.

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The analysis showed that present heating and cooling was very weakly counting on geothermal energy and that there was still high share of non-renewable sources. It is also evident that the municipalities do not count on shallow geothermal energy sources; they are not controlling the targets of National renewable energy action plan (NREAP) of Slovenia to reach 43 ktoe for heating and cooling from ground source heat pumps (including hydrothermal heat pumps) till 2020 and the shallow geothermal potential is not known to them. Overview of the public building stock in the municipality of Piran Noting the contents of Local Energy Concept (LEC) the total area of public buildings owned by the municipality of Piran is 159,680 m2. Of these, there are 26 public buildings (total area 37,824 m2), which are significant for the municipality as well as for energy situation analysis in the municipality. The kindergarten Morje is one of them. According to Real Estate Register data the Obalno-kraška region has 1,424 public buildings and flats, of which 287 are schools and kindergartens. The Municipality of Piran has 287 public buildings and flats, of these 146 are schools and kindergartens (Table 2). Table 2. Public building stock in numbers (Real Estate Register). Municipality of Piran

Obalno-kraška region

School / kindergarten

146

287

detached or free-standing building

124

179

semi-detached or twin house

0

0

first or last of the row house

0

5

row house in the middle

11

16

n.a.

11

87

Public building / flat

364

1,424

detached or free-standing building

209

651

semi-detached or twin house

0

10

first or last of the row house

8

39

row house in the middle

20

40

n.a.

127

684

Figure 3 shows public building stock, location of the selected public building kindergarten Morje for the pre-investment analysis and typical geological situation in the municipality of Piran.

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Figure 3. Public building stock and typical geological situation in the municipality of Piran.

Figure 4. Statistics of energy efficiency of schools and kindergartens from Local energy concepts of the municipality of Piran (2009).

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LEGEND PROJECT


From the LEC of the Municipality of Piran we have summarized the basic energy data of selected schools and kindergartens. The first assessment of the energy efficiency of the building shows an energy number that represents the annual energy consumption per heated net floor area. Energy performance certificates (EPCs) rate how energy efficient a building is, using grades from ‘A’ to ‘G’ where ‘A’ is the most efficient grade. Figure 4 show that public buildings in the municipality of Piran have a major part of energy - efficient rating performing buildings (‘D’ rating) for heating however, all without the use of renewable energy sources (only heating oil and liquefied petroleum gas). Target value for public buildings is 80 kWh/m2/y2 . According to LEC the municipality of Piran has 13 from 26 examined public buildings that have higher energy number than 80 kWh/m2/y. The kindergarten VVZ Morje in Lucija is one of the 20 % of the most wasteful schools and kindergartens in Piran (class F) (Figure 4). Assessment from LEC (2009) shows: heating costs 15,478 € / year (31,641 litters LPG: 6.9 kWh / litter; 1452.38 m2), energy number 150 kWh / m2. Table 3 shows the total amount of energy consumed in public buildings in the municipality of Piran. Table 3. Total amount of energy consumed in public buildings in the municipality of Piran (LEC, 2009). Parameter

Extra light fuel oil [l/y]

LPG [l/y]

Total

Amount of fuel consumed

212,994

123,672

-

Energy consumption for heating [kWh/y]

2,129,940

853,357

2,983,279

Annual costs for heating and ventilation [€]

_

_

454,674

Electricity consumption [kWh/y]

_

_

1,187,153

Annual costs – electricity [€]

_

_

205,912

2. 2. 2. Forecast of expected shares of RES for the heating and cooling of public buildings in the municipality of Piran Figure 7 gives an indication of the expected growth of ground source heat pump technologies in the heating and cooling sector as provided in National renewable energy action plan (NREAP).

Figure 5. Development of GSHPs in the heating and cooling sector in Slovenia. 2 Tomšič, M. Sodobni pristopi in orodja za spremljanje in nadzor rabe energije v stavbah ter hitro in robustno oceno potenciala učinkovite rabe in rabe obnovljivih virov energije v javnem sektorju, Gradbeni inštitut ZRMK d.o.o., 2006

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To achieve this target in national level, the municipalities need to step up their efforts to strengthen skills and include investments in ground source heat pumps in their Local energy concepts. The table below gives an estimation of the needed investments in ground source heat pumps by 2020 for the Obalno-kraška region. Table 4. Estimation of achieving the targets for GSHPs in accordance with the NREAP for the Obalno-kraška region.

Objective 2013-2020 for GSHP in Obalno-kraška region [GSHP / year] New construction

Reconstruction

<30 kW

7

>30 kW

1

<30 kW

17

>30 kW

2

Sum

27

2. 3. Consistency of the investment project with the development strategy of Slovenia, EU guidelines, spatial planning documents and other long-term development programmes and policies, by also taking into account the consistency of policy areas An investment is in line with policies and objectives specified in the following strategic documents: Directives in the field of renewable energy sources and energy efficiency in buildings • Climate Action and Renewable Energy Package • Directive EPBD: Directive 2010/31/EU of the European Parliament and of the Council of 19th May 2010 on the energy performance of buildings • Directive 2012/27/EU: Directive 2006/32/EC of the European Parliament and of the Council of 25th October 2012 on energy efficiency • Directive 2010/30/EU: Directive 2010/30/EU of the European Parliament and of the Council of 19th May 2010 on the indication by labelling and standard product information of the consumption of energy and other resources by energy-related products • Directive 2009/125/EC: Directive 2009/125/EC of the European Parliament and of the Council of 21st October 2009 establishing a framework for the setting of Eco design requirements for energy-related products • Directive 2009/28/EC: of the European Parliament and of the Council of 23rd April 2009 on the promotion of the use of energy from renewable sources • Directive 2004/8/EC: Directive 2004/8/EC of the European Parliament and of the Council of 11th February 2004 on the promotion of cogeneration based on a useful heat demand in the internal energy market Legal bases for energy performance of buildings • Spatial Planning Act • Construction Act • Construction Products Act • Energy Act • Energy performance certificate - Rules on the methodology of construction and issuance of building energy certificates: Energy performance certificate contains three indicators which reflect energy needs (delivered) for heating (kWh /

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LEGEND PROJECT


m2∙year); final energy use (delivered) for HVAC systems and lightening – space heating and cooling, hot water preparation, operation of ventilation systems, (de)humidification and lightening (kWh / m2∙year); and related CO2 emissions (kg / m2∙year) (calculated from delivered primary energy). For non-residential buildings and public buildings an operational rating certificate is considerate following the procedure energy metering according to SISTEN 15603 (Figure 14). The indicators are presented with the use of a sliding scale. • Rules on feasibility study of alternative energy systems for energy supply in buildings • National Energy Programme • National action plans • National efficiency energy action plan for the period 2008-2016 • National renewable energy action plan 2010-2020 (NREAP) Building technical regulations and technical guidelines for the construction • Rules on efficient use of energy in buildings (PURES-2) and obligatory technical guidelines for construction (TSG-1-004) in line with EPBD: In compliance with the regulation the energy performance in buildings is achieved by fulfilling the minimum requirements for: • maximum U-values of the envelope elements • maximum allowed specific transmission heat losses (Ht’), • maximum annual heat demand for space heating and for residential buildings also for cooling (Qnh, Qnc), • maximum primary energy for operation of the energy systems (incl. lighting) • minimum requirements for systems • Public buildings must comply with 10% more severe requirements! • The use of RES is mandatory in all new buildings since 2008, i.e., min. 25% of total final energy use for operation of the energy systems in the building must be covered by RES. This requirement can be fulfilled also if the share of RES used for space heating and cooling and hot water is obtained in one of the following ways: at least 25 % from solar energy, 35 % from gas biomass, 50 % from solid biomass, 70 % from geothermal energy, 50 % from heat from environment, 50 % from CHP (combined heat and power), 50 % from energy efficient district heating / cooling; or if the building demonstrates at least 30 % lower annual heat demand than defined in the minimum requirements; or by installation of solar collectors for hot water (min. 6 m2 / residential unit). Minimum requirements apply to all new buildings as well as to major renovations (renovation of at least 25 % of the surface of the building envelope). For minor renovations only the minimum requirements for U-values of the envelope must be considered. • Technical guideline paper TSG-01-004:2010 Efficient use of energy • Rules on the ventilation and air-conditioning of buildings Municipality strategies Parallel to the preparation of the strategic and programming documents for the period 2014-2020 at the national level, Regional Development Programme 2014-2020 for South Primorska region (working version, 19.5.2014) for municipalities of the Obalnokraška region is being prepared. Regional development programme defines regional development potentials and the strategic objectives of the development at the regional level and the relation with the national strategic objectives. Regional development programme and agreements for the development of region defines the measures and projects, which are regional or sectorial in character. Energy Efficiency and Renewable Energy Sources are specified in document.

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Table 5. Measures in connection with geothermal energy in Regional Development Programme 2014-2020 for South Primorska region. Subject

Project

Proposer

Purpose

Estimated value/ Financing source

Coverage in OP/ Priority axes

Sustainable energy EE, RES

Research of utilisation heat from sea water and geothermal energy potential in region Project idea

Urban municipality Koper, municipality Piran

The aim of this study is to research and estimate potential for energy utilisation of heat from the sea water and geothermal sources; and with feasibility study to point out technical possibilities for utilisation and economic viability of such projects.

2.1 mio

2.3. Sustainable use, energy production, smart grids

Local Energy Concepts (LEC) On the basis of Energy act municipalities must accept the Local energy concept (LEC). LEC is an important tool in planning strategy of municipal energy policy (an analysis of existing situation of energy use and energy supply, a proposal relating to the measures to be taken to maximizing energy efficiency). LEC is the basis for the preparation of Sustainable Energy Action Plan (SEAP). The Covenant of Mayors The Covenant of Mayors is the mainstream European movement involving local and regional authorities, voluntarily committing to increasing energy efficiency and use of renewable energy sources on their territories. By their commitment, Covenant signatories aim to meet and exceed the European Union 20 % CO2 reduction objective by 2020. A Sustainable Energy Action Plan (SEAP) is the key document in which the Covenant signatory outlines how it intends to reach its CO2 reduction target by 2020. It defines the activities and measures set up to achieve the targets, together with time frames and assigned responsibilities. Currently there are 11 SEAPs in Slovenia and none of those in the Obalno-kraška region. Regulations supporting geothermal energy exploitation Various programmes are in place in Slovenia, through which non-returnable funds are available for the energy renovation of public buildings and installation of renewables. For the investment cases in renewable technology the most representative is the Operational Programme for Developing Environmental and Transport Infrastructure 2007-2013 (OPDETI). The main priority areas for allocation of financial support are: • Energy restoration and sustainable use of buildings in the public sector - low energy and passive buildings, use of modern heating technologies, air conditioning and environment friendly decentralized energy supply systems with emphasis on renewable sources and cogeneration; • Efficient use of electrical energy: implementation of measures in industry, public and service sectors; • Innovative local energy supply systems: more extensive individual systems and remote and joint systems for production of heat and electrical energy, with emphasis on renewable energy sources and cogeneration; • Demonstrational and pilot projects and energy consulting programmes, informing programmes and training of energy users, potential investors, energy services providers and other target groups. Operational Programme for the implementation of the EU Cohesion Policy in the period 2014-2020 is published as working document (24th April 2014).

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LEGEND PROJECT


Incentive programmes supporting GE exploitation Currently available financial incentives for energy efficiency improvement and renewable energy sources in buildings in Slovenia: • Eco Fund: Eco Fund is a state owned fund. Eco Fund publishes public calls for subsidies for investments in energy efficient (re) construction and renewable energy sources. It provides soft loans with a favourable interest rate to legal entities, entrepreneurs and citizens, and grants to citizens and certain public legal entities (municipalities). Normally there are public calls to citizen ready for investments in installation of renewable heating systems (solar, wood biomass, heat pumps), windows replacement, thermal insulation of the facade, attic and rooftop, installation of heat recovery ventilation, thermostatic valves and hydraulic balancing, construction or purchase of low-energy or passive house, purchase of apartment in multi-dwelling buildings, built or reconstructed in passive standard (Qh ≤ 15 kWh/m2a). Subsidies to municipalities are for buildings occupied by public educational institutions (schools, kindergartens, libraries etc.), newly constructed of renovated in passive standard. • Cohesion Fund: The non-returnable subsidies from Cohesion fund financing for energy restoration and sustainable use of buildings are being be used for restoration of public buildings and low energy new public buildings (school buildings, buildings for research and homes for elderly people). In the heat sector for heating and cooling, the support is provided for investments in the construction of new heating systems and reconstruction of existing heating systems, as well as for incentives for connection of new users to already existing capacities (geothermal heating systems, solar panels, biomass boilers in the public sector, service sector and industry, biomass district heating systems at 1 MW, local biomass district heating systems up to 1 MW, heat pumps). The greatest share of grand resources was used for investments in biomass. Calls for proposals to receive financing from EU fund are published by Ministry of Infrastructure and Spatial Planning of the Republic of Slovenia (MZIP). In the following an example of tendering for grant for 100 % co-financing operations for the energy-saving building restoration owned by local communities is given. The tender documents are published on a web page of Ministry of Infrastructure and Spatial Planning of the Republic of Slovenia - http://www.energetika-portal.si/javne-objave/arhiv-energetika/javni-razpisi/r/javnirazpis-za-sofinanciranje-operacij-za-energetsko-sanacijo-stavb-v-lasti-lok-937/. Table 6. Criteria for assessment of an application: POINTS Specific savings from energy use (heating and electrical energy) in kWh/m2/a

Max. 40%

0< x< 50 (using the formula: Points= 0.6* Specific savings)

0 - 29.99

50≤ x< 300 (using the formula: Points= 0.04* Specific savings+ 28)

30 - 39.99

≥ 300

40 30%

Specific level of investment €/MWh/a of final energy savings (heating and electricity)* ≥ 4,000

0

1,000≤ x< 4,000 (formula: Points= - 0.01* Specific level of investment+ 40)

0 - 29.99

< 1,000

30

30%

Share of renewable energy sources or heat generation from cogeneration after implementation of rehabilitation <1

0

1≤x≤5

10

5 < x ≤ 10

20

10 < x ≤ 50

25

> 50

30

*Specific level of investment is the total eligible costs of operation divided by the provided annual energy savings resulting from energy renovation.

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The project’s consistency with the policy areas Directive 2009/28/EC on the promotion of use of energy from renewable sources sets binding targets for renewable energy (20 % share of renewable energy in the EU overall energy consumption by 2020). Slovenia has to reach individual targets set out in NREAP for the overall share of renewable energy in energy consumption, including low-enthalpy geothermal energy. Article 4 of the Directive 2012/27/EU requires from Member States to establish a long-term strategy for mobilising investment in the renovation of the national building stock (by 30th April 2014). National strategy is not yet elaborated (http://ec.europa.eu/ energy/efficiency/eed/article4_building_strategies_en.htm). Article 5 of the Directive 2012/27/EU requires from Member States either to renovate each year (from 2014 to 2020) 3% of the floor space of their public building stock in eligible buildings that does not meet minimum energy performance standards, or to take alternative measures to achieve equivalent energy savings by 2020 in eligible public buildings.

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LEGEND PROJECT


3. An analysis of market opportunities 3. 1. An analysis of the business environment Availability of companies with experiences in the installation of GHPs and the availability of experts for the design of GHPs in Slovenia is satisfactory. Presently there are more than 30 companies involved in the installation of GHPs in Slovenia. There are currently four major manufacturers of GHPs and three smaller ones in Slovenia. In the domestic market there are about 20 drilling companies which deal with capturing for GHPs. Shallow geothermal energy is an activity that requires high cooperation between different professionals – energy expert, driller, geologist and installer. Above all as these systems require solutions that need to be adapted to the local natural conditions - on site solutions, which are different from case to case (not copy-paste solutions).

3. 1. 1. The potential of shallow geothermal energy in the Obalnokraška (Coastal-Karst) region Within the LEGEND project we prepared on the Geological Survey of Slovenia a typical cross-section for the Coastal-Karst region, for the purpose of presenting the potential of shallow geothermal energy.3

Figure 6. Geothermal data for typical cross-sections in the Coastal-Karst region. A geological cross-section through the territory of the Coastal-Karst region (Figure 6) extends from the sea coast near Koper over the Karstic edge and Slavnik mountain to Matarsko podolje area. From the cross-section it is obvious that layers of limestone heavily dominate. Layers of flysch dominate in the coastal part, up to a depth of several hundred meters. Other layers are thin and are almost not visible in the cross-section. These are layers of clay, silt, sand and gravel from marine debris and alluvium sediments of Rižana, Badaševica, Dragonja and other streams in the periphery. These layers are up to 40 m thick.

3 http://www.legend-geothermalenergy.eu/si/publications/

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1. Favourable aquifer for pumping of groundwater: The most common water - water: In the Coastal-Karst region no highly abundant regional aquifers are present, for which would be considered to be highly favorable for the water – water HP system. The medium abundant aquifer is an alluvial backfilling of Rižana River in its lower part, roughly from a village Bivij above the Ankaran crossing to the coast in Koper. Yield of the aquifer is favorable between Sermin and the coast. It would also be suitable for higher intake of shallow geothermal energy from groundwater, however, it should be noted that groundwater is more saline close to the sea (it accounts for about one-third the salinity of the sea) and that its level is almost at the surface. For this reason, it is necessary to pay special attention to protection against corrosion and to reinjection of pumped water back into the aquifer. In the area of Rižana alluvial aquifer the settlements are relatively small, the aquifer is relatively limited and could not handle the uncontrolled expansion of geothermal heat pumps. Because the aquifer is hydro-dynamically of closed type and relatively thin, this can lead to interactions between the wells or between the pumping and reinjection well at a greater distance, as is usual with open aquifers. When making the capture it is particularly important to determine in detail the impact of the intake radius and the possibility of geothermal short circuit between the pumping and the reinjection well. It is expected that the potential of this aquifer will be in the future certainly utilized. 2. Favorable soil for excavation: Common Ground - Water horizontal pipes, baskets, piles, water - water (Figure 6 - light blue color) Except in the Rižana river valley the alluvium depositions of rivers and streams in the region are low abundant aquifers (valid for valleys of Badaševica, Dragonja, Drnica, Osp River and other streams). The reason for this is the worse permeability and thinner wetted parts of the aquifer. In the urban area of Koper, the groundwater flows in the alluvial backfilling of Badaševica. In this aquifer there are already few intakes, including geothermal heat pumps of water – water type, but they are small amounts of water that are most suitable for family dwelling buildings and homes. Wetted aquifer layer is thin, however, yield of the aquifer and the intake feasibility are necessary to be identified in detail from place to place. These sediments are very suitable and simple for horizontal and vertical excavations; consequently different shallow heat exchangers prevail there with a much cheaper execution than drilling. These are horizontal heat exchangers (geocollectors) at a depth of 1.5 to 2 m below the surface, or from 4 to 8 m deep energy baskets of 4 to 5 m in diameter. Marine depositions (eg. in the area of Bonifika in Koper) are unfavourable regarding the construction stability, so the foundation piles are often used there. With the installation of heat exchangers in the piles we get the energy piles, which are both structural element and the energy source for heating and cooling. 3. Most frequently ground – water, vertical/horizontal (Figure 6 – brown color) The characteristic of flysch layers is an alternation of sandstones and marls and quite thick top layer of weathered or fractured rocks. Because of this top layer it is possible to carry out simple excavations to depths of 1.5 to 2 m in a large part of the flysch territory. In these cases very suitable are horizontal heat exchangers as buried pipe loops, spirals and other. Usually they are regularly installed in excavated trenches and filled up with backfill and excavated soil. In some places, up to a depth of 4 meters or more a rather simple excavation with backhoe is possible. In this case, installation of energy baskets is very convenient and inexpensive. In places with shortage of space in the vicinity of the building, vertical or borehole heat exchangers (BHEs or geoprobes), installed in the boreholes, are a matter of consideration. Drilling in flysch layers is relatively cheap, but challenging. Driller must be prepared for a quick change of the rock hardness. Even at greater depth driller must reckon with the possibility of unconsolidated or softer layers and options of water intrusions through particular fracture. In such cases, there may be caving of borehole or problems with the installation of BHEs. Driller must be aware of the risks and equipped to deal with any problems that arise. Flysch layers are an aquifer only when local or limited sources of groundwater appear. Groundwater occurs more in separate point, usually from cracks in the sandstone, from contacts between layers or from fault zones. Forecast of inflows and the well yield in these layers is always associated with the risk and may not be 100% reliable. In the case that the borehole encounters water, longer pump testing is recommended, possibly during the low water conditions. It is possible to prove the stability of groundwater recharge and its quality and only on this basis it makes sense to install water – water type of installation system. Due to these uncertainties, the water – water system is a disadvantage for the investment planning in these layers and must in the background include the backup option solution with BHE. Groundwater in flysch layers has a beneficial effect on the efficiency of BHE, as its flow can provide a much faster regeneration of heat or cold in the vicinity of BHE. This may render geothermal heat pump to work at more favourable temperature, resulting that relationship between acquired and an input energy is increased.

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4. Most frequently ground – water, vertical (Figure 6 – green color) There are usually very little weathered rocks in the Karstic territory, built by limestone rocks. Very rarely is on the surface such a soil, which would be favourable for the excavation and installation of horizontal systems. Locally, however, where layers of clay, gravel and the like exist (for example in the uvala’s, dry valleys, etc.), the possibility for horizontal system is certainly expediently to be exploited. However, while designing it should be noted that the values of geothermal parameters here are lower than in the wetted moist soil on flysch layers. It is therefore necessary to consider that it is likely dry noncohesive soil. This can be improved by replacing the soil and by backfill buried pipe loops with a more favorable material, which must be established by geologist or designer. Limestone Karstic territory constitutes a normal solid rock, which is generally more favourable than flysch for drilling and installation of BHEs. The risk that occurs in such drilling and on which driller should be ready, are mainly Karstic caverns. Before planning the BHEs it is necessary to ascertain what is the probability of encountering the caverns, and then in accordance with this to anticipate appropriate solutions (such as shallow boreholes and greater number of boreholes, reserve boreholes, over casing the caverns and the like). Limestone has good thermal conductivity and may even be better than the flysch layers. However, planning the greater BHE fields in the karstic rocks is questionable. Due to the variety in rock fracturing and karstification it is difficult to reckon with homogeneous characteristics of the entire BHE field, especially on a big field with multiple BHEs. Limestone layers are very unfavourable as an aquifer. Their permeability and yield is extremely variable, ranging from very low abundance in solid rock to high abundance in the caverns and Karstic channels. Massive limestone, which is free of cracks, is impermeable almost as concrete. In addition, it is difficult to predict the quality of the water. We need to make sure what is turbidity of the water during the rains and what is the temperature fluctuation between summer and winter time. In the Karstic aquifer water level in a large part of the territory is very deep below the surface (> 50 m), as well as it varies considerably as a function of rainfall (up to 100 m and more).

Figure 7. The suitability of the site for a type of geothermal heat pumps (GHPs) and public buildings in the real estate registry (The Surveying and Mapping Authority of the Republic of Slovenia).

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3. 1. 2. Rapid estimation of geothermal potential on the site of the building Hydrothermal energy: Utilising seawater (heat extracted from seawater) or other surface water is certainly the most attractive option for heating and cooling. If we are allowed to install hydrothermal heat pump water to water with coefficient of performance COP = 5, we should construct pumping station with capacity of at least Q = 5.72 l/s (Figure) for acquisition of heating capacity QH = 90 kW. The temperature differences no more than dT = 3 °C between abstracted and returned water is taken into account.

Q=

1 ) COP (dT • 4,2)

QH • (1 –

For cooling with the same cooling capacity QC = 90 kW (COP = 5, dT = 3 °C) we should have the capture with pumping capacity Q = 8.57 l/s.

Q=

1 ) COP (dT • 4,2)

QC • (1 +

The kindergarten Morje in Lucija town is located around 1 km from the sea-coast; building plot is located at altitude around 4 metres above the sea. Despite its vicinity to the sea we have assumed that the distance in the given case is too large. If in the future appears to be realized such a project, the sea water would be probably captured with the objective of district heating, within the meaning of overall solution for several important public buildings, because it can be also an environmental problem and consequently environmental costs follow. Geothermal energy from groundwater: The Obalno-kraška region is characterized by having relatively small territory with medium and high yields of aquifers with high potential for exploitation of shallow geothermal energy. If we want to carry out a geothermal heat pump system with heating capacity of 90 kW, we should provide pumping capacity of 5.72 l/s, the same as for hydrothermal heat pump (Figure 8). Also a construction of one or more pumping wells and rejection ones should be taken into account.

Figure 8. Graph for the assessment of required capacity of an aquifer with regard to desired heating capacity. Below the surface land of kindergarten Morje the aquifer yields, which can ensure reliable option for BHE and exploitation of geothermal energy from groundwater, are not available. The options for capture of hydrothermal energy from sea or geothermal energy from groundwater in the particular case were not studied. For this uncertainty an option for geothermal capture with closed loop system has been studied. Hydrothermal system from surface water and geothermal system from groundwater are systems, which allow both heating and cooling. Geothermal energy from soil: Over a wide area of kindergarten Morje the soil is favourable for shallow excavations. However the kindergarten is located in dense residential neighbourhood agglomeration for which we find out that due to space limitations it is not possible to figure neither on horizontal heat pump exchangers nor on energy baskets.

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Nevertheless, we wanted to get a rough estimation of horizontal heat pump exchanger size. For a single-dwelling building we can assume a rough estimation after the Standard SIST EN 15450:2007, p. 27, which resumes (summarizes) the German standard VDI 4640 – second part (Table 7). Table 7. An example of geothermal specific heat extraction for an estimation of required area for installation of horizontal heat exchanger (4, p. 27).5 Soil quality

Specific heat extracted from soil (5, p. 27)

Operating hours, 1800 h/year

Operating hours, 2400 h/year

Dry, non-cohesive soil

10 W/m2

8 W/m2

Moist cohesive soil

20 to 30 W/m2

16 to 24 W/m2

Moist sand and gravel

40 W/m2

32 W/m2

For central Europe is typical to bring the heat carrier fluid temperature entering the condenser to 12 K during continuous operation. It has to be properly projected so that temperature difference does not cause problems. In a given land for cohesive moist soil and for 2,100 operating hours per year a specific heat extraction 23 W/m2 could be presumed. After this estimation and for smaller capture up to 30 kW the area of about 1,250 m2 would be required in case of square of about 35 x 35 m. For 3-times bigger capture we may conclude that 3-times bigger area would be needed. In order to get precise estimation we should carry out a detailed dimensioning or modelling. Literature with data on methods for quick assessments and dimensioning of energy baskets was not found. We assumed empirical assessment, which says that with one energy basket with a depth of 5 m it is possible to cover about 1 – 3 kW. For coverage of 90 kW some 30 baskets would be need. Because the soil is favourable for shallow excavations, this is an interesting option. Baskets could be placed deeper; perhaps even 7 – 8 m which in turn would took significantly less space than horizontal collectors. However, this option is not discussed hereinafter; we were focused on more complex investment with the geoprobes (BHE). In any case it is necessary to consider the possibilities for energy baskets wherever the soil is favourable for shallow excavations up to depth of 4 – 8 m. In a territory where soil excavation is feasible to depths of 4 – 8 m, the possibility of using energy baskets should be urgently addressed. These may represent, for example, also a supplement or covering peaks for existing systems. Horizontal system is appropriate only for heating, while the energy baskets can be appropriate also for cooling or for peak energy storage. BHE: While there are possibilities for groundwater capture related to areas with good aquifers beneath the surface, the BHEs can be adjusted to great majority of different geological conditions. Also for smaller BHE (to 30 kW) a tools for quick estimation can be useful (6 , p. 27). If we consider specific extraction value from aforementioned standard, which is for sandstone 65 W/m, we would need (after very rough estimation) 462 m of probes for capture with capacity of 30 kW. And for three similar captures total is over 1300 m. In a given case of kindergarten Morje we adopt that the solution with BHE has probably the highest potential. The space for the execution of probes is located south of the building in an undeveloped gap, which serves as children playground (Figure 16). It may also be located north of the building in the undeveloped gap, which is presently available green area between the buildings. The probes can be arranged also in straight line along the boundaries of the parcels and in this way we can reduce the impact on environment in very small area.

4 SIST EN 15450:2007, p. 37 5 SIST EN 15450:2007, p. 37 6 SIST EN 15450:2007, p. 37

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The main advantages of BHE are 7: • Their stability in the sense of productivity: • If correctly dimensioned the BHE systems are more powerful than air source heat pumps, due to minor temperature changes of energy source (this is the temperature of the soil in comparison to air temperature), • Heat loss in the hydraulic system is minor due to lower working temperatures; • Higher share of renewable energy • Possibilities of its use for cooling and in particular also passive cooling without the use of a compressor.

3. 2. Review of climatic and geological data During the first phase basic spatial data should be collected, required to take decision on investment in shallow geothermal energy. Therefore a GIS viewer has been designed for the entire area of the Adriatic region. The viewer provides several databases, namely, topography and land uses of the area; geological and hydrogeological settings; thermal and hydraulic parameters depending on the properties of soil, climate data, water protection areas and locations of public building stock. To display different data each layer can be switched on or off (Figure 9). Data and information resources: Slovenian Environment Agency (climate data, water protection areas), Surveying and Mapping Authority of the Republic of Slovenia (topographic data, building stock), Geological Survey of Slovenia (temperatures at depths of 100 m and 250 m, hydrogeological map – IAH and LAWA, litho-geochemical map, map of potential for geothermal heat pumps), Ministry for Agriculture, Forestry and Food (land use). More and more public data are already in the open access. Climate data: Climate data are accessible on the web site of Slovenian Environment Agency. In dynamic modelling of building energy balance data of the test referential year can be used. Test referential year represents 365-day series of hourly values of selected meteorological variables, which are necessary for calculation of the energy balance of a building. Files with the referential year include hourly data of air temperature, relative air humidity, series of mean global solar irradiance on a horizontal plane in the hour prior to the given time, mean wind speed and direction in the hour prior to the given time.8 Other climate data are: consecutive day in a year of entry and end of heating season, degree days deficit, average monthly and yearly temperatures, project temperatures for 30-years period 1971 - 2000. These data are available for optional location (GKX, GKY).9 Coordinates of the treated building (GKX, GKY) can be obtained by use of Environmental atlas of Slovenia10.

7 Monnot, P., 2012. Guide technique. Les pompes à chaleur géothermique sur champs des sondes. Manuel pour la conception et la mise en oeuvre. ADEME & BRGM, Paris.104 p. (p. 9). 8 http://meteo.arso.gov.si/met/sl/climate/tables/test_ref_year/ 9 http://meteo.arso.gov.si/met/sl/climate/tables/pravilnik-ucinkoviti-rabi-energije/ 10 http://gis.arso.gov.si/atlasokolja/profile.aspx?id=Atlas_Okolja_AXL@Arso

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Table 8. An estimation of distribution of required annual energy demands for heating and cooling in months. (Own calculations; data resources: Slovenian Environment Agency for stations 136, 158 and 464, daily values of degree days deficit (outdoor temperature T < 12 °C) and cooling degree days (outdoor temperature T > 21 °C)).

Postojna 136 [%]

Nova vas na Blokah 158 (without 2002) [%]

Portorož 464 (without 1991) [%]

Month

Heating

Cooling

Heating

Cooling

Heating

Cooling

1

18

0

17

0

22

0

2

16

0

15

0

20

0

3

14

0

13

0

16

0

4

9

0

9

0

6

0

5

3

1

4

1

0

2

6

1

20

1

22

0

20

7

0

46

0

47

0

40

8

0

32

1

30

0

35

9

2

0

4

0

0

3

10

7

0

8

0

4

0

11

13

0

12

0

12

0

12

17

0

16

0

20

0

One of important boundary conditions for GSHP dimensioning is also average monthly or daily temperatures of the ground. These data are available for different stations in Slovenia at depths from -2 cm to -100 cm.11 The huge number of practicable data on current measuring and statistics, for example on solar irradiance, air temperature, wind speed and direction, are available on web site of ecological stations of Nova Gorica and Koper.12 Geological, hydrogeological and geothermal data: Geological, hydrogeological and geothermal data have been collected and compiled by Geological Survey of Slovenia. On the bases of such data cartographic information are updated, like Basic geological map, lithostratigraphic units, hydrogeological map, and geothermal map, register of boreholes and base of geological profiles. Some data are available in digital format. For orders of the data, which are not freely accessible through website, is necessary to complete a form, which is available in electronic form on the website.13 Geological Survey of Slovenia is preparing a map of temperatures at the ground surface (T0). This is one of the basic information for the BHE dimensioning. The map will be based on the data from geothermal measurements in the boreholes and will assist in the dimensioning of geothermal heat pumps. If you decide for dimensioning, for example of geoprobes (BHEs), you can verify at Geological Survey of Slovenia whether there is any borehole in the vicinity of discussed building from which you can get the most comparable measured geothermal data. Water protection areas: Water protection areas are visible on the Environmental atlas of Slovenia6. For a specific area information on the ordinance or decree indicating the safeguard measures may be obtained. From this it is evident what are the limitations or conditions, which are relevant for the execution of shallow geothermal systems.

11 http://meteo.arso.gov.si/met/sl/climate/tables/yearbook/2012/ 12 http://193.95.233.105/econova2/ (http://www.koper.si/) 13 http://www.geo-zs.si/podrocje.aspx?id=113

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Figure 9. Print screen of LEGEND viewer (map of ground temperatures at depth of 100 m). Already issued water rights: In the Environmental atlas of Slovenia are also data on already issued water rights. This allows you to check whether in the vicinity of discussed building there is already another well in use.

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3. 3. Review of energy data Construction data about the building are required for definition of dimensional and thermal properties of the building (heat losses) and for calculation of required heating power. These data can be obtained from existing project documentation (first design, the project for acquiring the building permit, the project for the tender, the project for execution, energy audit), the missing information is often gained from caretaker. For public buildings some energy data are available also in Local energy concepts and in particular in Energy audits.

3. 3. 1. Critical review of existing energy audit of selected building The kindergarten Morje is located in Fazanska ulica 3, 6320 Portorož. The main part of kindergarten was constructed in 1976, it was extended in 1989 (Figure 10, Figure 11, Figure 12, Figure 13). The roof was renovated in 2009. The windows were renovated only in the kitchen.

Figure 10. Northern side of the building where the kitchen is situated.

Figure 11. Northern and western side of the building.

Figure 12. Northern side of the building where classrooms are located.

Figure 13. Eastern and southern side of the building where classrooms are located.

An existing gas boiler by which the building is heated has power of 145 kW. In Energy audit a required heating power was calculated to 109 kW (Table 9). Required energy for heating was estimated to 166.34 MWh after static calculation. Table 9. Data from Energy audit of kindergarten Morje, project heat demands of kindergarten (p. 38).

External project temperature T

-6.0

°C

Internal project temperature T

21.0

°C

Transmission heat loss HT

85.59

kW

Ventilation heat loss HV

23.34

kW

Projected power

108.93

kW

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From data referred to Energy audit (2010) some ambiguities proceed: • How much energy is actually consumed for cooling with air condition? It is only an estimation, that for ventilation and air conditioning 35 % of electrical energy is consumed, which is approximately 30,149 kWh (average over three years 2007 2009), or 4,294.15 EUR. • How much energy is consumed for domestic hot water? In winter, the domestic hot water is heated from heat plant, which is gas boiler and in summer from wall-hung gas boiler. In both cases the energy consumption for domestic hot water is not specifically measured. From such results the conclusions over the costs of few thousand EUR for domestic hot water can be drawn. What is the average energy consumption through several seasons and does the consumed energy have increasing or decreasing trend. In general 3-year data on actual energy consumption for heating and cooling are recommended. In existing Energy audit some data are given only for one year (for example data on energy consumption and energy costs for heating). Energy costs for heating and cooling from Energy audit (2010) deviates very much from costs identified from invoices received in 2013. In 2013 the costs were significantly higher. Because there is no long-term analysis, it is not clear what are the annual fluctuations and what is true value. For this reason it is necessary to use calculated, modelled values for the BHE dimensioning. In 2013 an inventory of energy consumption for that year and thermographic measurements were carried out in the kindergarten Morje. Losses were detected due to leakages from windows as possible consequence of poor installation. Losses are obvious also at junction of the foundation plate and the outer wall, perhaps as result of poor insulation of the foundation plate. The humidity of the indoor air is on average favourable – between 41 and 52 %; however, the humidity fell also to only 30 % during the measurements. An average indoor temperature was between 21.7 and 22.6 °C at the end of the heating season.14 Heating temperature range is 70/50 °C. Final energy, supplied for heating from liquefied petroleum gas was 204 MWh. For preparation of domestic hot water and hot water for kitchen 76 MWh of final energy were consumed, but it has not been possible to specify the share of domestic hot water. It has been established that in the building some 30 air conditioning units with power up to 3 kW are found, but it has not been possible to specify the share of electric energy consumption for cooling in total consumption. For more accurate estimation of energy consumption for domestic hot water (DHW) we can use two methods:

l kW Q[W]=1,163 • QDHW[ day ] • (Tt – Th)=74,63 day • 242 days =18,06 MWh Tt = temperature of hot water (60 °C) Th = temperature of cold water (13.5 °C) QDHW = consumption of domestic hot water (5 l/day/per child, staff member x 276 children and staff members) = 1,380 l/day. An average consumption of hot water after SIST EN ISO 13790 would be 10 kWh/m2/year, which is total 15.86 MWh/year, or approximately 16 MWh/year (taking into account the heated floor area of the building, i.e. 1,586.4 m2). Table 10. Display of calculation of the costs of final energy and delivered useful energy. A

B

C

D

E

F

Costs identified from invoices received for

Costs [€] from invoices without VAT 2013

Final energy [MWh]

Costs for final energy without VAT [€/MWh]

Efficiency [%]

Useful energy [MWh]

Heating

25,150.63

204

123.37

82

167

DHW+kitchen

8,669.90

76

113.5

92

70

Electricity

17,724.36

130

136.69

100

130

TOTAL

51,544.89

410

367

14 Gjerkeš, H., Stegnar, G., 2014. Nadgradnja in dopolnitev energetskega pregleda določene stavbe z dodatnim ukrepom plitve geotermalne energije v okviru projekta LEGEND. GI ZRMK, Ljubljana. 32 str.

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Table 11. Display of calculations of the energy demands for building (delivered and exported heat) and of the costs for heating and cooling. G

H

I

J

K

Consumer

Share of energy from invoices [%]

Share of useful energy [MWh]

Energy demands – delivered and exported [MWh]

Costs [€] for heating and cooling without VAT

Heating

100

167

167

25,150.63

DHW

23

16

16

1,994.08

Cooling (COP air-conditioner = 3)

17

22

65

2,959.97

TOTAL

248

30,104.68

Table 12. Display of method for calculations of results in the tables above (Table 10, Table 11). Step

Calculations

1

B/C=D

2

CxE=F

3

FxH=I

4

I = J (except for air-conditioner in which case the default value for COP is 3, and the electric energy consumption is 3-times smaller than it is energy demand for cooling)

5

K=HxB

The needed amount of energy for cooling (65 MWh – Table 11) could not be possible to be estimated neither from invoices nor from other existing data. In fact this value can be only assessed by modelling.

Figure 14. Digital orthophoto map and cadastral data of area where the kindergarten Morje is situated.

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3. 4. An analysis of the existing prices Energy prices increased in the period 2008-2012. In the same period, the most increased price was for the natural gas industry (almost 53 %), followed by price for natural gases for households by 38%, price of heating oil, for household electricity, price of petrol NMB 95, diesel D2, and the least increased price was for electricity for industry, for less than 6%.15 Figure 17 shows the comparison of final energy prices in Slovenia for heating in EUR/MWh for a period from 2007 to 2013.

Figure 15. Economic efficiency – energy prices for heating (SURS; http://www.biomasstradecentre2.eu; MGRT; Nike Krajnc, 2013, Stanje na trgu z lesnimi gorivi, EGES konferenca, H. Gjerkeť, 1LF)

15 http://kazalci.arso.gov.si/?data=indicator&ind_id=637&lang_id=94

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3. 5. SWOT analysis with setting targets The current status of awareness and information availability about shallow geothermal is still limited. Policymakers do not understand the overall role that ground source heat pumps can play in the entire energy sector. People are informed in general what is geothermal energy, but do not know what is shallow geothermal energy. Actually, engineering shallow geothermal systems do not require any extraordinary natural conditions when looking for a source; the main challenge is to make good use of local geological conditions. The barrier for massive ground source heat pump implementation is relatively high initial investment. Nevertheless, the low operation cost and comfort are among the numerous benefits of this application. STRENGTHS • Availability of the resources – mostly everywhere, there is variety of heat exchangers’ applications that could be adapted for all natural conditions. • There are financial subsidies for RES within which GSHP is included (cash grants, loans at lower interest than market rates, lower interest on investment). • Application procedures for GSHP are not more complicated than for other types of RES. • Low environmental impact, including CO2 emissions. • Significant energy cost savings. • Availability of professional design experts. • Availability of experienced installation companies. • Security of energy supply during the building’s life. • GSHP systems can ensure the steadiest performance throughout the year.

OPPORTUNITIES • Favourable natural conditions for GSHP implementations: elaboration of expert bases for achievement of the highest possible degree of energy self-supply in respect of local natural conditions. • Combining/coupling GSHPs and other RES technologies. • There are 4 bigger national producers of GSHPs. • Article 5 of the Energy Efficiency Directive requires from Member States, each year from 2014 to 2020, either to renovate 3 % of the floor space of their central government building stock in eligible buildings, which do not meet minimum energy performance standards, or to take alternative measures to achieve equivalent energy savings by 2020 in eligible buildings owned and occupied by central government. In Slovenia 3 % of the government building stock, both national as well as municipal public buildings, should be considered. • Energy performance certificates of a building: large public buildings have obligation to display an energy performance certificates – this enables to facilitate decision-making by the definition of priorities of refurbishment also according to the shallow geothermal potential criteria. For example, owners of the buildings situated on highly productive shallow aquifers should be informed that water to water system could be the most economical favourable solution.

WEAKNESSES

THREATS

• Cost of the sub-soil preparation (e.g. drilling) compared to the fossil-fuel systems

• Bad practices of shallow geothermal sources applications (lack of continuous trainings for the professionals).

• Profitability depends on the fossil fuel energy prices (the ratio of natural gas prices and electricity tariffs, obligations to district heating connections and gas networks)

• Lack of information about legislation and regulation framework for the public prevents people from investment in the GSHPs.

• Complex implementation (case-by-case design, multiple professions involved) • There is no Slovenian Association for GSHPs • Lack of transparency of CO2 fees: the public have a negative opinion about the CO2 fees and other RES and EE (energy efficiency) contributions in the energy price - it looks like we all pay more costly energy in order to ensure incentives for individuals. Purpose of the fees is lost due to wrong interpretation.

• Uninformed public is convinced that GSHP is not renewable source because electricity is used for the operation. • To prevent conflicting uses in the case of massive GSHP introduction these activities should be registered.

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4. Analysis of the options with an estimation of project costs and benefits and efficiency calculations for the economic useful life of the investment Selected building in Obalno-kraška region was a kindergarten in Piran (cadastral municipality number: 2631 - Piran, cadastral number of the plot: 5483/2, ID number of the building: 3758). The kindergarten is situated in highly populated area and is within a 1000 meters radius from sea coast (air distance). GKY: 391536 GKX: 41074 Z: 3.9 m a.s.l. Lat: 45o30’19.73’’ (45.505481o) Lon: 13o36’25.90’’ (13.607193o) ETRS89 X:391166, ETRS89 Y:41559

Figure 16. Siting of the kindergarten Morje. A selected building kindergarten Morje was built in 1976 (Figure 17). The analysed building has no basic insulation, the roof is not insulated, heating is central with old boiler of very low efficiency, windows and doors are old with very poor insulation properties. It is a building that requires a comprehensive energy refurbishment. For the selected building the existing LEC of the municipality of Piran (OIKOS, d.o.o., 2009) and Energy survey (EL-TEC Mulej, d.o.o., 2010) were reviewed and analysed. The results of existing Energy survey were upgraded from the experts in the field of civil engineering and energetics (ZRMK, d.o.o., 2014).

Figure 17. Kindergarten Morje in Local energy concept (Lokalni energetski koncept občine Piran – I. Analiza stanja, 2009).

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4. 1. Modelling of energy needs for delivered energy to the building and preparation of proposal for investment In existing Energy audit (2010) of the Municipality of Piran investments and organizational measures are proposed as well as estimations of costs and savings for the kindergarten Morje. In the table below two largest proposed investments and the sum of all the other proposed measures are given (Table 13). Table 13. Selection of proposed available measures from Energy audit (2010). Measure

Investment / payback period

Energy savings [MWh]

Savings [€]

Reconstruction of facades and replacement of windows

137,630.18 € / 20.5 years

100.4

6,726.37

Reconstruction of the heating station

22,100.00 € / 24.3 years

13.5

909.89

All proposed measures

171,130.00 € / 19.8 years

123.2

8,630.00 29.495 T CO2

BHE provides heating and cooling. For this reason, we adapted its scenarios by modelling the measures and we assumed the installation of a ventilation system that could replace air conditioners (Table 14). Table 14. Description of scenarios for modelling the building energy demands (conditions of renovation) and measures for cost reduction of heating and cooling. Scenario

Condition of renovation, measures

Baseline (BL)

Baseline without investments in the renovation. Building in the present state.

Option 1 (O1)

Replacement of heating system with GCHPs and *installation of mechanical ventilation with heat recovery

Option 2 (O2)

Renovation of the building envelope (PURES 2, 2010) without any works on heating system

Option 3 (O3)

Replacement of heating system with GCHPs, *renovation of the building envelope (PURES 2,2010) and installation of mechanical ventilation with heat recovery

*The mechanical ventilation is assumed to be with 80 % heat recovery and exchange rate 0.81 L / (m2 s); (Rules on the ventilation and air-conditioning of buildings, OG RS, n. 42/2002) For the chosen building a 3D dynamic model of thermal response of building elements (programme IDA Indoor Climate and Energy v4.6) and estimation of heat rating of building was performed by an external expert for building physics. In the table 15 below the climate data and general characteristics of building are given that have been used for dynamic modelling.

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Figure 18. 3D Model of the building in the programme IDA ICE v4.6.

Table 15. Climate data and general characteristics of the building that have been used for dynamic modelling. Climate data

Value

Unit

Data source

Ambient temperature

Deg-C

ARSO

Ambient humidity

%

ARSO

Diffuse component of solar radiation

W/m2

ARSO, Strahlung method

Direct normal component of solar radiation

W/m2

ARSO, Strahlung method

X component of direction of the wind speed

m/s

ARSO

Y component of direction of the wind speed

m/s

ARSO

General characteristics of the building

Heated area

1,586.4

m2

Heated volume of the building

4,553.2

m3

Building envelope area

4,199.1

m2

Factor Awindows/Abuilding_envelope

5.7

%

Average heat transfer of the building components

0.5884

W/(m2K)

Form factor

0.9222

m2/m3

36

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Table 16. Data on building envelope and heating and cooling systems. Heat transfer of the building envelope components

Value

Unit

Data source

External wall

0.69

W/(m2K)

Energy audit (EL-TEC, 2010)

Roof

0.53

W/(m2K)

architectural plans

Floor on the ground

0.46

W/(m2K)

architectural plans

Windows

2.63

W/(m2K)

valid rules during the construction

Windows (kitchen)

1.40

W/(m2K)

valid rules during the construction

Doors

0.71

W/(m2K)

assumed

Usage regime of the building

Users of the building

4

h/day

SIST EN ISO 13790

Lightening

1

W/m2

total 1500 hours of operation

Total internal sources

4

W/m2

TSG-1-004:2010

Heating and cooling systems

Internal temperature set in summer

26

°C

SIST EN ISO 13790

Internal temperature set in winter

20

°C

SIST EN ISO 13790

Rules on the ventilation and air-conditioning of buildings

Two-stage heat pump COP

3

Projected power of heat pump

90

kW

Calculated after SIST EN 12831

Temperature regime of heating distribution

70/50

°C

Interviews with housekeeper

Radiators dimensioned in the model in relation to thermal loads

145

kW

Energy audit (EL-TEC, 2010)

Average use of hot water

10

kWh/m2/year

SIST EN ISO 13790

Maximal power for individual air conditioners

3000

W

field inspection, survey

In the modelling of the existing condition of the building an energy expert wanted in the first place to calculate the energy consumption for heating to be close to the actual measured as much as possible. Therefore, a larger number of simulations were performed with different projected internal temperatures. At an internal temperature of 20 °C the difference between the energy required and measured energy for heating was about 50 %. The best approximation to the measured energy consumption was obtained at an internal temperature of 24 °C. The measurements of the micro-climate in the rooms also lead to the conclusion that the internal temperature is actually higher than 20 °C. So it was agreed that for modelling of actual situation and other scenarios projected internal temperatures of 24 °C in winter and 26 °C in summer are to be assumed.

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Table 17. Delivered energy for heating and cooling according to the different projected internal temperatures. Projected internal temperatures

Delivered energy for heating

째C

MWh

20

101

22

129

23

144

24

161

25

182

Final results of the modelling scenarios are dynamic hourly and monthly values of delivered energy and energy exported (feedin energy) to achieve the agreed project internal temperatures (Table 17). From the dynamic hourly needs for delivered and exported energy we can predict the necessary power of heat generator (Figure 19, Figure 20, Figure 21). These are also the input data for more detailed geothermic design of shallow geothermal field and geothermal heat pumps.

Figure 19. Delivered energy to the kindergarten Morje for heating and cooling, present position (ZRMK, 2014).

Figure 20. Delivered energy to the kindergarten Morje for heating and cooling, after building envelope renovation (ZRMK, 2014).

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In case of renovation of building envelope the energy expert calculated the most optimal power of heat generator with which the minimum requirements for the internal temperature will be achieved with regard to the installed radiators. A heat generator with 55 kW and 58 kW has been tested. Table 18. Monthly needs for delivered / exported energy of building: comparison of the results obtained in modelling of four different scenarios. Projected internal temperature

24 °C

State of renovation

Baseline, BL

Option 1

Delivered energy

Qf,h

Qf,c

Qf,h

Qf,c

Qf,h

Qf,c

Qf,h

Qf,c

Month

kWh

kWh

kWh

kWh

kWh

kWh

kWh

kWh

January

36344

342

32566

314

23268

263

23948

271

February

27230

577

24138

507

17132

298

17249

324

March

20963

951

19722

808

13280

425

12571

441

April

10602

1857

10329

1264

6335

842

5436

587

May

2420

5139

2420

3078

1117

2026

433

1007

June

235

12708

250

11481

56

6308

0

5519

July

34

17778

3

17188

0

9338

0

9627

August

12

16707

1

15420

0

8830

0

9591

September

1658

6382

1516

5166

686

3008

168

1982

October

9773

1483

9596

1071

5921

684

4712

478

November

21808

451

19967

395

13921

279

13477

285

December

29906

388

27478

352

19540

278

19076

288

Option 2

Option 3

Annual needs Calculated

MWh

161

65

148

57

101

34

97

30

Calculated

kWh/m2

102

41

93

36

64

21

61

19

Measured

MWh

167

167

167

167

Measured

kWh/m2

105

105

105

105

Baseline variant is the existing situation – conventional energy sources (LPG heat plant), with heat requirement 161 MWh/a. Option 1 variant is replacement of heating system with GCHPs and installation of mechanical ventilation with heat recovery and energy consumption 148 MWh/a, of which at least ¾ is renewable. Option 2 variant is renovation of the building envelope - external walls and windows, leaving 101 MWh/a of energy demand. Option 3 variant is replacement of heating system with GCHPs, renovation of the building envelope and installation of mechanical ventilation with heat recovery, with lowest heat requirements of 97 MWh/a. Coverage ratio: Coverage ratio with heat pump is defined as a ratio between heat provided with heat pump and total delivered heat for heating of a building and domestic hot water preparation (intersection of red and orange curves on the graph below). Geothermal heat pump with 60 kW heat output can ensure 82 % of heat energy from geothermal energy for space heating in building, which is more than 70 %. In accordance with Article 16 of the Regulation on efficient use of energy in buildings (PURES-2) the energy efficiency of the building is achieved.

Pre-investment analysis for large Ground Source Heat Pump investments in Obalno-kraška region

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Figure 21. Delivered energy to the kindergarten Morje for heating and cooling (present demands) in relation to coverage ratio.

4. 2. Geothermal input data for modelling the abstraction (intake) of shallow geothermal energy An overview of the range of geothermal parameters in the area shall be readily identifiable from the ready-section. For a more detailed assessment of the on-site planning investment the interpretation of geothermal specialist is needed. For land, where kindergarten Morje stands, the results of previous research on the territory between Piran, Portoro탑 and Lucija have been collected by a geologist. The structure of the geological layers at depth has been predicted on the basis of already drilled boreholes in the near and distant surroundings. The kindergarten Morje is located in the part of the Slovenian coast, which is built on the surface of the Eocene flysch. In the area of kindergarten the flysch layers are almost horizontal. The layers of marl, sandy siltstone and coarse carbonate sandstone interchange. In them, at a depth of -90 m a layer of calcarenite, up to 5 meters thick, has been determined. In the area of the Portoro탑 Marina the flysch rocks are covered by 20 to 40 m thick package of recent marine sediments (clay), whose thickness decreases towards the slopes. Limestone of Paleocene age lie beneath the flysch rocks, approximately at a depth of -260 meters.

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Figure 22. The forecast of cross-section of geological strata in the kindergarten Morje area and valuation of geothermal parameters. The forecast of geological strata cross-section has been reviewed by hydrogeologist along with geologist. From the experimental data from other boreholes the hydrogeologist estimated that the permeability of the flysch was between 10-6 m/s (the greater part of sandstone) and 2.7 ∙ 10-7 m / s (the predominant component of marl). Effective porosity of flysch is estimated at 0.1%. Permeability of predominantly clay layers is certainly bad, probably only about 5 ∙ 10-9 m / s. In the area of kindergarten Morje probably more permeable sandstone rubble dominates in the upper few meters. Groundwater flow in the flysch is possible in sandstones or in cracked (fissured) parts of the rocks and in gravel slope and deluvium. Cracking of flysch decreases with depth, except in the area of fault zones. Also, the deeper part is dominated by less permeable marl. Most of the wells for groundwater exploitation in Lucija abstract the water from typical calcarenite layer. Their yield is from 0.5 to 1 l/s, however, there is also a hydraulic connection between them. This indicates that the shallow aquifer is very limited. The groundwater level in the Marina is about a meter below the surface. Hydrogeologist has made the following findings: 1. Groundwater level is shallow beneath the surface, even at a depth of 2 to 3 meters. Under the sea level the geological layers are certainly wet. 2. The geological layers in this area form a low-yield aquifer with local or limited sources of groundwater. With the most likelihood a low well yield can be expected, probably less than 2 l/s, perhaps also lower than 0.5 l/s, even with drilling more than 260 m deep. Although local major inflows are possible. With additional tests, it is possible to predict where in the wider area is a greater likelihood for occurrence of such inflows. However, the prediction of satisfactory abundance of the well cannot be 100 % reliable. 3. We estimate that the announcement of the desired flow rate of 6 l/s of water is rather uncertain in the given limited land area. Favourable yield could be proved only by testing well and test pumping. It would be necessary to determine with the test pumping whether the groundwater, which could be abstracted with a well, restores sufficiently and in constant quantity.

Pre-investment analysis for large Ground Source Heat Pump investments in Obalno-kraška region

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4. In depth of 260 m and more limestone layers can be expected. These are generally slightly more permeable and porous than flysch layers. In order to capture and demonstrate the desired water flowrate, a deep well of at least 350 m should be anticipated. 5. The land that is available at this kindergarten is too small to allow pumping and reinjection of water back into the aquifer. In this case, a geothermal short circuit would happen, because the flows of water are bound to the narrow and limited fractured zones or contacts between layers of sandstone and marl. Geothermal specialist is of opinion that the field borehole heat exchangers are reliable solution at a given site. He reviewed more specifically the data from geothermal borehole Lu-1 / 94. This shows the mean heat-flow density (q) of 40 mW/m2 at Lucija site, while the measured temperatures in this borehole show the expected temperatures of 19.5 °C at a depth of 285 m and about 28 °C at 800 m depth. Thermal conductivity of Eocene sandstones was measured at 2.0 W/(m∙K), for a well-permeable Cretaceous limestone to 2.61 W/(m∙K), while flysch marl has mean thermal conductivity of about 2.36 W/(m∙K). Geothermal specialist has estimated for the upper layers of silt and clay that their thermal conductivity is likely to 1.75 W/(m∙K). This value is chosen as he looked the average values of thermal conductivity for measured samples of clay and silt (Figure 23). This value was compared also with the recommended values, 1.4 to 2.4 W/(m∙K), which the Swiss standard SIA 384/6 (2010) provides for water-saturated clay and water-saturated sand. For flysch layers it was evaluated similarly, but slightly higher value, 2.25 W/(m∙K), than it is recommended for thermal conductivity of marl rocks (2.1 W /(m∙K)) in the SIA 384/6 (Table 10). Marl may be in fact somewhere also sandy, and in between there may also be layers of calcarenite. At depth of 94-99 m below the surface, we expect as much as 5 m thick layer of this calcarenite rock. Table 19. Estimation of average thermal conductivity λ [W / (m ∙ K)] of geological strata to a depth of 150 m in the land of kindergarten Morje in Lucija. λ ∙ D [W/K]

Thermal conductivity

Thickness of drilled strata

Share of flysch rocks

λ [W/(m∙K)]

D [m]

[%]

Clay and silt

1.75

24

Sandstone

2.00

37.8

30

75.60

Marl

2.36

88.2

70

208.15

Cross-section forecast to 150 m depth

42.00

Weighted average thermal conductivity at depth of 0 to 150 m

2.17

Weighted average thermal conductivity of flysch

2.25

Geothermalist has chosen a value of 2.22 MJ/(m3∙K) for volumetric heat capacity, slightly higher than the weighted mean value if taken from standard SIA 384/6 (Table 11). Table 20. Assessment of the average volume related heat capacity ρc [MJ/ (m3∙K)] of geological strata to a depth of 150 m in the land of kindergarten Morje in Lucija. Cross-section forecast to 150 m depth

Volumetric heat capacity (after SIA 384/6)

Thickness of drilled strata

Share of flysch rocks

D [m]

[%]

ρc ∙ D [MJ/(m2∙K)]

ρc [MJ/(m3∙K)] Clay and sand, water saturated

2.35

24

Sandstone

2.1

37.8

30

79.38

Marl

2.2

88.2

70

194.04

Weighted average volumetric heat capacity

42

56.40

2.20

LEGEND PROJECT


Figure 23. Thermal conductivity of rock samples from boreholes in south-western Slovenia (Prestor et al., 2013).

Figure 24. Thermal conductivity of rock samples from boreholes for the entire Slovenia (Rajver, geothermal data base).

Pre-investment analysis for large Ground Source Heat Pump investments in Obalno-kraška region

43


Especially for bigger BHEs (> 30 kW) it is considered that in addition to detailed predictions also detailed field measurements, particularly thermal response test (TRT) is necessary. This measurement is done in the initial boreholes by which it is determined the response of geological strata to extraction of heat, by which is clearly shown whether the undertaken projections are correct. On this basis the original plan of BHE can be upgraded and we can save a lot of money.

4. 3. BHE modelling For BHE modelling an analytical model Earth Energy Designer v3.16 was used. When setting location of BHE we were limited by the land use (uninhabited and unpaved surface without underground cables, conduits and installations) and with the ownership of the parcel.

Figure 25. Municipal parcel around the kindergarten, red hatching area in the north is possible location for setting BHE (min. 12 x 30 m).

44

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The input data for the design of BHE Table 21. Geothermic inputs parameters. Ground Properties

Thermal conductivity

2.170

W/(m.K)

GeoZS

Volumetric heat capacity

2.220

MJ/(m³∙K)

GeoZS

Ground surface temperature

13.5

°C

ARSO

Geothermal heat flux

0.040

W/m²

GeoZS

Borehole and Heat Exchanger (BHE)

Type

double-U

Diameter

110.0

mm

Outer diameter

32.0

mm

Wall thickness

3.0

mm

Thermal conductivity

0.420

W/(m∙K)

Shank spacing

70.0

mm

Filling thermal conductivity

0.60

W/(m∙K)

Contact resistence pipe/filling

0.0

(m∙K)/W

Borehole thermal resistence

Series factor

3

Heat carrier fluid

Thermal conductivity

0.480

W/(m·K)

Specific heat capacity

3795.0

J/(kg·K)

Density

1052

kg/m³

Viscosity

0.0052

kg/(m·s)

Freezing point

-14.0

°C

Flow rate

5.4

l/s

Seasonal performance factor (SPF)

Estimated average SPF (domestic hot water)

3

Estimated average SPF (heating)

3.2

Estimated average SPF (cooling)

2.2

Pre-investment analysis for large Ground Source Heat Pump investments in Obalno-kraška region

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Table 22. Input data for BHE costs estimates. Fix cost per borehole

400 €/borehole

Cost per drilled unit length

60 €/m

Fix additional cost per borehole

100 €/borehole

Cost per additional unit length of borehole

60 €/m

Total additional length of drilling

5 m/borehole

Cost per unit length of ditch

10 €/m

Fix initial cost Investigations and dimensioning

7,500.00 €

Works management

6,500.00 €

TRT – thermal response test

2,500.00 €

Heat pump HP 53 kW (B0W65)

13,571.43 €

HP 34,5 kW (B0W65)

10,178.03 €

reversible > 20 kW

766.50 €

Basic starting

284.70 €

Delivery

219.00 €

Module for cascade configuration of HPs

863.96 €

The selection of the configuration of the boreholes with regard to availability of space and drilling depths: We assumed that the investor chose Option 1 with heating, cooling and domestic hot water (O1_HCD). In basic solution of the configuration of the boreholes the following boundary conditions were set up: the space on north parcel of the building in the size of 30 x 12 m is available for drilling of boreholes. We were looking for those solutions where the geoprobes will not be deeper than 150 m, the distance between them will be between 5 and 10 m, the number of geoprobes will not be greater than 20. Then, we looked for two additional solutions for the same place. In one of them we set up the condition that all geoprobes are laid in a straight line, in order to occupy the minimum possible part of the parcel (Option 2). With solution 3, it was foreseen that the area of 30 x 12 m is oasis, which is available to be fully occupied with geoprobes. At the same time we wanted to carry out BHE with a depth of less than 100 m, to facilitate the difficulty of drilling, or reduction of the level of risk for implementation. With the fourth solution, it was assumed that the investor preferred solution with execution of boreholes in a straight line along the edge of the playground, south of the building and that the depth of geoprobes would be up to 120 m.

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Table 23. Optimization of borehole configuration with regard to availability of space.

Number of boreholes

Configuration

Spacing [m]

Depth [m]

Total depth [m]

Cost [€]

Boundary conditions

< 20

30 x 12 m

5 to 10

50 to 150

-

-

Solution 1

6

4 x 2 U-(type 111)

10

147

885

98,536

Boundary conditions

<20

30 x 5 m

5 to 10

50 to 150

-

-

Solution 2

7

1 x 7 in line (type 6)

5

134

941

102,490

Boundary conditions

< 20

30 x 12 m

5 to 10

50 to 100

-

-

Solution 3

10

6 x 3 U-( type 130)

6

98

981

107,543

Boundary conditions

< 20

60 x 5 m

5 to 10

50 to 120

-

-

Solution 4

8

1 x 8 in line (type 7)

9

115

922

102,463

Solution 1:

Solution 2:

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47


Solution 3:

Solution 4:

The impact of the geoprobes’ configuration on the effectiveness of BHE: At the end we assumed that it was necessary to finally decide between solutions 1 and 3. The first solution is the cheapest, while the second solution provides significantly shallower geoprobes - 98 m instead of 147 m. Due to reduction of the level of risk for implementation of boreholes the solution 3 is maybe better. The comparison of efficiency of the explained solutions is shown in figure below (Figure 26). The progress of temperatures of heat carrier fluid following the years of GCHP operation is more favourable in a denser and shallower BHE as indicated in figure below (Figure 26). This is even more obvious in the summer, when the difference from the second year of operation and up to 25 years of operation is around 2 °C.

48

LEGEND PROJECT


Figure 26. Comparison of maximum and minimum mean monthly temperatures of heat carrier fluid at two different boreholes’ configuration (Solution 1 and Solution 3).

4. 4. Benefit assessment for proposed solutions Technology of ground source heat pumps uses renewable thermal energy from the underground. It is very stable energy resource and available all over the area. Another benefit is that the installations are “invisible” (low noise and out of sight, low maintenance, low running costs). It can also contribute strongly to emission reduction (NOx, SOx, CO2 and particles to the air), reduces dependency on fossil fuels and contribute to primary energy savings (especially when using RES electricity, Solar PV installation or cogeneration systems using biofuel). There is no need to transport, distribution and fuel stock. The technology is very safe and there is no risk of fire, explosion, or fuel leaks. From the economical view, with the ground source heat pumps we can combine an efficient system for heating and cooling energy with no risk for availability 24 hours a day throughout the year. For 1 kWh of energy input we get 4 kWh of output. This means about 50 % savings in annual operating costs in both heating and cooling mode compared to a conventional system. These systems are very cost effective with a simple pay-back period of 2 to 10 years. The user is less sensitive for price changes on the energy market due to the high efficiency of such systems. Application potential is good in new building and renovation, residential (single, multi-family residency) and non-residential (commercial) buildings. Also important is its capability to store the energy surpluses in the ground and abstract it seasonally. The service life of these systems is very long (>30 years).

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4. 5. Project efficiency for the economic useful life of the investment This chapter provides information about the assessment of the investment costs in constant prices for proposed solutions. In upper part of the table below (Table 24) the calculated dimensions of BHE chosen by the minimum price criterion are given. In lower part of the table are given calculated mean temperatures of heat carrier fluid – fluid in the geoprobes. Marginal condition for mean temperature of heat carrier fluid was 0 – 30 °C. The first three scenarios are O1_H (only heating), O1_HC (heating and cooling) and O1_HCD (heating, cooling and domestic hot water). This comparison was calculated to show the importance of storage share of heat surpluses in case of cooling of the building. With storage of heat in the underground the cost of BHE construction is cheaper by a quarter. By the additional heating of domestic hot water the cost of BHE construction vary just a little. Scenario O3_HC is option 3 (heating and cooling). Scenarios O1_HC_L2 and O1_HC_L3 were being carried out by reason of sensitivity analysis of the calculation. The first scenario (O1_HC_L2) is calculated for case if the building with the exact heating demands like kindergarten VVZ Morje would be located in the area of Dragonja (in the hinterland of Izola and Koper), therefore in other and different geothermal conditions. The second scenario (O3_HC_L3) is in the same manner calculated for geothermal conditions in the area of Podgrad (limestone dominated conditions). Table 24. Results of modelling after different scenarios. Scenario

O1_H

O1_HC

O1_HCD

O1_HC_L2

O1_HC_L3

O3_HC

BHE and HP cost [€]

127,690.00

94,527.00

98,536.00

95,601.00

113,741.00

80,228.00

Number of boreholes

9

6

6

6

8

6

Length of boreholes [m]

149.21

136.36

147.50

139.34

138.55

130.26

Total length of boreholes [m]

1,342.86

818.15

884.97

836.05

1,108.39

781.56

Basic loads: mean temperature of heat carrier fluid (at the end of the month) [°C] after 10 years of operation JAN

1.81

0.29

0.47

0.43

0.38

0.69

FEB

3.58

3.29

3.32

3.15

2.21

3.53

MAR

4.6

5.11

5.04

4.79

3.31

5.77

APR

6.96

9.28

8.9

8.61

5.93

9.48

MAJ

9.13

14.31

13.56

13.19

9.1

12.54

JUN

9.92

23

21.59

21.15

14.66

16.76

JUL

10.2

28.97

27.09

26.62

18.52

20.62

AVG

10.38

28.37

26.5

26.1

18.24

21.21

SEP

10.15

19.34

18.08

17.86

12.58

15.39

OKT

8.2

12.23

11.42

11.38

8.11

11.8

NOV

5.47

6.86

6.41

6.46

4.69

6.96

DEC

3.28

3.09

2.94

2.99

2.23

3.66

50

LEGEND PROJECT


For each obtained design of BHE the balance of heat energy was calculated, extracted from the underground and electrical input to run the compressor, the circulation pumps and other heating needs that are not covered by geothermal energy (Table 25). Furthermore, the costs for electrical input to run the ground coupled heat pumps and all other heating needs of the building are calculated (needs for cooling or domestic hot water, it depends on scenario). Table 25. Balance of heat energy, extracted from the underground and electrical input to run heat pumps (calculated using the programme EED) and other heating needs that are not covered by geothermal energy.16 Cost [€/MWh]

BL [MWh]

O1_H [MWh]

O1_HC [MWh]

O1_HCD [MWh]

O2 [MWh]

O3_HC [MWh]

LPG for heating (123,37 € / 82%)

150.45

161

101

Cooling

65

65

34

Electricity for cooling COP = 3

136.69

21.7

21.7

11.3

Heat from ground

0

101.7

101.7

101.7

77.7

Electricity for HP - heating

136.69

46.2

46.2

46.2

19.4

Cool from ground

0

-83.0

-83.0

-39.1

Electricity for HP - cooling

136.69

25.9

25.9

8.7

Heat from ground – DHW

0

10.7

Electricity for HP – DHW

136.69

5.3

LPG for DHW

150.45

16

16

16

16

16

SAVINGS

0.0

114.8

110.5

121.2

70.4

154.6

ENERGY COSTS

29,591

11,690

12,273

10,594

19,152

6,249

Maintenance (1% invest.; estimation)

2,000

1,277

945

985

2,000

1,493

COST

31,591

12,967

13,218

11,580

21,152

7,742

SAVINGS

0

18,624

18,373

20,012

10,440

23,850

RES share17

%

3

66

76

81

3

78

16 During the calculation the 31.4% share of renewable energy in the electricity mix was taken into account.

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51


5. Impact analysis with a description of the major impacts of the investment from the environmental acceptability perspective 5. 1. Environmental impact analysis The main environmental impacts associated with ground source heat pump systems are listed below (17). • All ground source heat pump systems can result in undesirable temperature changes in the ground and the water environment with impacts on water quality or aquatic ecology. • Both open loop systems and closed systems installed at depth can result in the interconnection of different aquifer units during drilling - affecting water quality or flow. • Closed loop systems may contain thermal transfer fluids which are toxic and can pollute groundwater when leaking. Open loop systems present the following additional environmental risks: • Localised increase in groundwater levels which could affect adjacent structures. • The potential impact of groundwater abstraction on the environment or other users of groundwater or surface water. Developers of open loop systems should contact the Environment Agency at an early stage to discuss the intended location, proposed design, and operation of their system. Developers of closed loop schemes with possibility of the environmental risks, such as within a groundwater source protection zone, should also contact us at an early stage. Significant consideration must be given to the design of both open and closed loop schemes in order to ensure their longevity and efficient performance. Such design considerations do not fall within our competence. A significant increase of the applications could have relevant effects on the reduction of polluting emissions, and therefore on the pursuit of targets of the European strategy on environment and energy.

5. 2. Efficient use of space, in accordance with the needs of regional development and sustainable development of the society Selected building and surrounding land is not located in any protected areas (e.g. Water Protection Areas). Locations of sewer pipes, water supply network, gas network, heat energy network are shown in Annex 4.

17 http://www.gshp.org.uk/pdf/EA_GSHC_Good_Practice_Guide.pdf

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6. Human resources’ analysis by individual options and an analysis of the impact on employment from the economic and social structure perspectives Availability of companies with experiences in the installation of ground source heat pumps and the availability of experts for the design of ground source heat pumps in Slovenia is satisfactory. Presently there are more than 30 companies involved in the installation of ground source heat pumps in Slovenia. There are currently four major manufacturers of ground source heat pumps and three smaller ones in Slovenia. In the domestic market there are about 20 drilling companies which deal with capturing for ground source heat pumps. Shallow geothermal energy is an activity that requires high cooperation between different professionals – energy expert, driller, geologist and installer. Above all as these systems require solutions that need to be adapted to the local natural conditions - on site solutions, which are different from case to case (not copy-paste solutions). Presently, unfortunately, we do not have reliable examination into market development and market growth. Consequently, it is certainly less capacity for joint appearances and promotion in a wide range of offers of energy sources. In addition, the estimation of the total contribution of shallow geothermal energy to renewable energy sources is less reliable. It would be advisable to establish cooperation and trust between the administration and market holders of ground source heat pumps, as this would facilitate the exchange of key information for a reliable analysis of the situation on the ground source heat pump market. In this way, the market can be more effectively directed and can adapt faster for bringing a new technology forward. At the same time this participation would allow more reliable estimation of market growth and the annual contribution of GHPs within the total balance of renewable energy sources. The Slovenian experts in designing of ground source heat pumps have performed many larger complexes of low enthalpy geothermal installations. At least 60 cases are actually known from a separate research, while according to recent inquiring concluded there are about 220 shallow geothermal systems in the country with a capacity in range between 20 kW (kilowatts) and 1000 kW. These systems demonstrate that competence in the design of shallow geothermal systems in Slovenia is available. The presence of domestic manufacturers, designers, installers and drillers facilitates the GSHP solutions to be adapted to individual needs of clients and at the same time that the particularities offered by the natural conditions and advanced technology are optimally exploited. The “Settlement 15th May” in Koper (residential sector) is the first major facility in Slovenia, which uses energy foundation piles for heating (67 apartments with 6,200 m2, plus office and retail spaces with 3,400 m2). The foundations piles are necessity in this part of Koper due to soft silty soil rocks in depths of several tens of meters. More precisely, of total 240 foundation piles there are 192 energetic foundation piles functioning as BHEs. For the preparation of the heating and cooling medium, a reversible HP is built in the central engine building. It uses Earth’s thermal energy by two modules delivering 250 and 200 kW of heating power. Operation of the system in the summer time is reciprocal to operation in the winter. In the summer time, the produced cold is used in the buildings, while waste heat is used for hot water; the difference is stored through boreholes into the earth. A Slovene civil engineering company SGP Pomgrad GNG d.o.o. (Slovenska Bistrica) developed the system together with designers and architects of Slovene companies Veling-Deol d.o.o. (Lendava) and Studio Kalamar (Ljubljana). The second outstanding practice which has to be demonstrated is the new Pipistrel Research & Development building (productive sector). Its footprint measures 2,400 m2 and has been designed as environmentally friendly and emission-free and to be completely energetically self-sufficient using renewable energy sources (RES) alone. The construction of the building was a huge challenge, especially since it represents a big short-term expense while the results of nature protection are only visible in long-term. The building incorporates geothermal heat exchangers in symbiosis with a large geothermal accumulation field. A total of 1,200 metres of vertical geothermal BHEs provide approximately 36 kW of thermal energy. BHEs are connected to the

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“geothermal accumulation field” so that it is also possible to run the system without using the heat pump on days when pumping the heat transfer medium around the building suffices. As requirements for the higher or lower temperature of the medium arise, the heat pump is activated by the system automatically. Spare heat is accumulated inside the “geothermal accumulation field”. The heart of the building is one of Slovenia’s largest solar power plants, which (combined with a cogeneration module) covers all energy needs of the building, electricity and thermal energy conditioning included. Air conditioning is established in an innovative and efficient manner using ground radiation heating and cooling. This allows for the minimum possible temperature difference between highest and lowest fluid temperature in the building and yields maximum efficiencies and reduced costs. Economic savings (pay-off period and other economic indicators) were intentionally not considered in the project, as the environmental benefits outweigh them by far. Being energetically independent in the case of energy use limitations in the future was more important. The figure below (Figure 27) shows the numbers of installed GSHP units and employment in the ground source heat pump sector in Slovenia on the basis of information from the Rajver et al., 2014 and GEOTRAINET, 201118. Based on the estimations from the report of GEOTRAINET project, 201119 for 1 ground source heat pump installation, the following professionals are directly needed: 1 designer - 1 working day; 2 drillers plus 1 assistant - 2 working days; 1 HP installer plus 1 assistant - 2 working days. In total, 1 GSHP system requires 10 working days. If we consider we have 210 working days per year, and 930 GSHP units have been installed in 2010, the total number of jobs in the sector is= 930 (units) * 10 (working days) = 9300 (days); 9300 (days) / 210 (days/year) = 44 workers. We can estimate that the GSHP sector counts for around 44 direct jobs in 2010. A GSHP system required also many other professionals: manufacturers of HP and other materials (manifold, pipes, circulation pumps etc.), geological surveys, licensing bodies, etc. The HP business represent a large number of professionals. The ratio on indirect jobs is estimated to be: 7 indirect jobs for 1 direct employee in the sector. In total, the GSHP sector employs today more than 350 persons with the indirect jobs created by the development of GSHP systems. Numbers of installed units

Employment (direct and indirect jobs)

Figure 27. Numbers of installed GSHP units (left) and employment (right) in the GSHP sector in Slovenia.

18 GEOTRAINET, 2011. DELIVERABLE, D 1. Annual survey on GSHP market growth. Dostopno na: http://www.geotrainet.eu/moodle/file.php/1/ Publications/Geotrainet_Publications/D01.GSHP_annual_survey_February_2011.pdf project EurObserv’ER. 19 GEOTRAINET, 2011. DELIVERABLE, D 1. Annual survey on GSHP market growth. Dostopno na: http://www.geotrainet.eu/moodle/file.php/1/ Publications/Geotrainet_Publications/D01.GSHP_annual_survey_February_2011.pdf project EurObserv’ER.

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7. An indicative timetable for implementing the investment with investment dynamics by option Procedures for thermo technical system elaboration, geological investigation, implementation design, authorization procedures (except for closed loop systems with boreholes up to 300 m, which are not situated in aquifers, protected areas and areas under threat, or where deposits of coal or hydrocarbons are located), installations of boreholes, installations of thermo technical system (heat pumps) and installations of monitoring system takes about 1 year. Table 26. Timetable. Months Thermo technical system elaboration: building physics

2

Geological investigation, borehole test, TRT

2

Implementation design

2

Authorization procedures: permission not required for closed loop systems with boreholes up to 300 m, which are not situated in aquifers, protected areas and areas under threat, or where deposits of coal or hydrocarbons are located.

 -

Installation - boreholes

3

Installation - thermo technical system: heat pumps and ventilation with heat recovery

1

Monitoring system

2

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8. An indicative financing structure for each option, including the obligatory analysis of the reasonability of using public-private partnership concept The financial structure provides to cover of the investment value from three sources: • Cohesion Fund, • National budget, • Municipal budget. In the table below is given only indicative financial construction of the project scenarios. Table 27. Indicative sources of co-financing, current prices in EUR. Total (VAT incl.)

Cohesion Fund*

National budget

Municipal budget

Share in %

100

70

15

15

O1_H [€]

127,690.00

89,383.00

19,153.50

19,153.50

O1_HC [€]

94,527.00

66,168.90

14,179.05

14,179.05

O1_HCD [€]

98,536.00

68,975.20

14,780.40

14,780.40

O1_HC_L2 [€]

95,601.00

66,920.70

14,340.15

14,340.15

O1_HC_L3 [€]

113,741.00

79,618.70

17,061.15

17,061.15

O3_HC [€]

80,228.00

56,159.60

12,034.20

12,034.20

* http://www.eu-skladi.si/ostalo/navodila-za-izvajanje-kohezijske-politike-2007-2013/navodila-za-fu

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9. A calculation of financial and economic indicators 9. 1. Investment from a perspective of financial and economic indicators For comparison of represented cases of the BHE implementation a calculation of economic indicators and calculation of internal rate of return of investments was used (adapted after standard SIA 480). The choice of economic indicators: • Value of capital, • internal rate of return, • payback time, • annual net income and • cost price for unit of exploitation. The selection of one or more indicators is performed, depending on the specific issues on which the calculation of profitability answers. In this case we are interested in the payback time and annual income (Table 28). A period of calculation was set at 30 years, which is also the maximum life time of one of the components of investment (Table 29). Used real interest rate is 1.56%. VAT is not taken into account. Changing of prices is not taken into account.

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Table 28. Guide comparison of selected economic indicators of modelled options.

Option 1 H

Option 1 HC

Option 1 HCD

Option 2

Option 3 HC

Period of calculation [years]

30

30

30

30

30

Value of capital [€]

271,493

298,297

333,306

57,259

258,298

Internal rate of return [%]

11.25

14.57

15.47

3.53

6.74

Payback time [years]

9.0

7.0

6.7

21.8

14.0

Annual net income [€/year]

11,401.15

12,526.76

13,996.92

2,404.56

10,847.01

Cost price for unit [€/MWh]

83.43

78.78

72.70

120.61

85.72

Table 29. The comparison of the levels of investments for modelled options [€]. Investment

Option 1 H

Option 1 HC

Option 1 HCD

BHE

104,753

70,890

GCHP

22,938

Ventilation

27,000

Option 3 HC

Lifetime

74,900

68,694

30

23,638

23,638

11,535

18

27,000

27,000

27,000

25

191,334

191,334

30

191,334

298,563

Facade and windows Total

154,691

121,528

125,538

Option 2

On the basis of calculations carried out we can join the options 1_HCD and 3_HC to already proposed measures from the existing Energy audit (2010). In this way the pre-investment analysis is accompanied by an additional solution with shallow geothermal energy (Table 30). Table 30. Option 1_HCD and Option 3_HC include shallow geothermal energy for further economic analysis together with those already provided by investment measures from the existing Energy audit (2010) (see Table 13). Scenario

Condition of renovation, measures

Investment [€]

Payback time [years]

Savings [MWh]

Savings [€/year]

Savings [T CO2/year]

BL

Without investments - building in the present state

0.00

-

0.0

0.00 €

0.000

Option 1 HCD

Installation of mechanical ventilation with heat recovery + GCHP

125,536.00

6.7

121.2

18,997.56 €

21.718

Option 2

Renovation of the building envelope (PURES 2, 2010) without any works on heating system

191,334.00

21.8

70.3

10,439.92 €

28.888

Option 3 HC

Renovation of the building envelope (PURES 2, 2010) + installation of mechanical ventilation with heat recovery + GCHP

298,562.00

14

154.6

23,343.53 €

47.308

Calculations of the carbon dioxide equivalence (for the case of the kindergarten Morje): CO2 equivalence (electricity) [tonnes CO2/year] = 0.060496 ∙ 3.6 ∙ Electrical energy [MWh] ∙ 2.8 CO2 equivalence (LPG heating) [tonnes CO2/year] = 0.071056 ∙ 3.6 ∙ LPG useful energy [MWh] ∙ 1.02/0.82 CO2 equivalence (LPG DHW) [tonnes CO2/year] = 0.071056 ∙ 3.6 ∙ LPG useful energy [MWh] ∙ 1.02/0.92

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9. 2. A specification of the costs and benefits that cannot be evaluated in terms of money In seeking of optimal forms and ways of implementing energy reconstruction of such buildings with wider social importance as kindergartens are, it shall not be limited only on financial indicators. It is important that measures where the multiplier effect is the widest have a priority. Renovation of the building should be based also on those factors related to the quality of life in building and environmental indicators, not merely on economic indicators. Geothermal energy can provide a significant contribution to the reduction of the negative impacts that current systems for heating and cooling in our living and working environments have on ground, water and air. Some important benefits are descripted in chapter 4.4.

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10. A risk analysis and a sensitivity analysis for each option A risk and sensitivity analysis for calculations of dimensioning from the range of geothermal parameters can be done in two ways: 1. We assume that the building will be renovated with the same energy needs as in Option 1 with heating, cooling and domestic hot water. This building is located: a) In the first case, at the site of the kindergarten VVZ Morje in Lucija (O1_HCS), b) In the second case, at the area of Dragonja (in the hinterland of Izola and Koper), also in flysch ground, but different geothermal parameters (O1_HCD_L2), c) In the third case at limestone karst ground above the karst edge of the Podgrad (O1_HCD_L3). A comparison of model calculations show that for the building with the same needs a very similar BHE is required, also in the area of Dragonja in the hinterland of Izola and Koper. Execution would be little cheaper. If the building with the same needs would be placed in the area Podgrad, the BHE should be larger. The investment would be higher for ca. 15,000.00 â‚Ź, which is 13 % more than for the building in Lucija (Table 19). 2. We assume that the kindergarten VVZ Morje will be renovated after Option 1 with heating, cooling and domestic hot water (U1_HCS). Some key geothermal parameters in different possible ranges were used during dimensioning. Maximum ranges are when selecting values for thermal conductivities of rocks. These parameters also have the significant impact on dimensioning. In the particular case the choice between two extreme possibilities means about 30,000.00 â‚Ź in assessing of investment. Variations in the assessment of individual parameters are cumulated. This is a good example why a thermal response test (TRT) for bigger BHE systems, mainly for BHEs above 30 kW or the BHE fields, is necessary to foresee. Therefore, we can predict a construction of two boreholes, and undergo TRT later when it comes to final execution; the boreholes can be included in the BHE field.

Figure 28. Deviation in estimation of investment with regard to selection of main geothermal parameter values.

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11. Presentation of the appraisal criteria and weights for the selection of the optimum variant For comparison of represented cases of the BHE implementation a calculation of economic indicators and calculation of internal rate of return of investments was used (adapted after standard SIA 480). The choice of economic indicators (Value of capital, internal rate of return, payback time, annual net income and cost price for unit of exploitation) are presented in chapter 9.

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12. A comparison of the options with a proposal and a justification of the choice of the best option (optimum variant) We assume that in a given case in feasibility study it is necessary to examine the possibility of implementation of Option 1_HCD. If we consider that the lifetime of BHE is at least 30 years, in the meantime we can expect that the savings might be invested in new building envelope. The savings at the cost of savings from Option1_HCD can be invested in new building envelope from Option 1 already after 17 years of operating the ground coupled heat system. By that the need for delivered and consumed energy would be lower and heat pump with capacity of 55 kW would be adequate. In consequence, afterwards the BHE will be significantly more energy efficient (higher SPF) and cost effective. The energy costs for heating and cooling would be in that case more than 4-times less than the present-day (Table 30). In addition to the proposed solution with Option 1_HCD, the expert for energy and investor can compare other solutions with integration of ground source heat pumps. That is, for example, preserving gas station for covering peak loads and installation of geothermal heat pump with lower rated power and higher coefficient of performance. The second solution is partial covering of building demands of individual building parts. These solutions are depended on further plans with building, where it is being understood mainly how the renovation will proceed in the next years – with kind of dynamic and similar. It is also important how the owner will draw up the list of renovations that the impact of investments will be the maximal. From here forward imagination of the project designers opens. A challenge is to combine possible solutions with other renewable energy sources, extra thermal energy storages and similar. Furthermore the challenge is in details, how to cover peak loads, which usually present few tenths of a percent of total energy demands and how to use specific features of a certain building and natural resources on the site. In the planning of larger ground source heat pumps systems (from 30 kW upwards) the most innovative group of energy experts, architects, installers, drillers and geologists must work, all with good distributed mutually tasks. Such systems should not be projected, for example, just by an energy expert or a driller.

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13. Annexes Annex 1: Energy consumption assessments – heating, hot water and electricity, actual energy use and expenses. LEC Piran, I. analysis of the situation (2009)

Energy survey (2010)

ZRMK (2014)

Heated floor area of the building [m2]

1,452.38

1,786.70

1,586.4

Energy source

Liquefied petroleum gas (LPG)

Liquefied petroleum gas

Natural gas

Reference year

2008

2009

2013

*Average (2007, 2008, 2009) Amount of fuel consumed [m3]

31,641

Cost [€]

15,478

24,720 (conversion)

31,025 (conversion)

+ Kitchen & heating DHW in summer: 3,061; 2,240 (conversion)* 14,947 + Kitchen & heating DHW in summer: 5,935.26; 5,600*

Energy consumption [kWh]

285,560 (conversion)

Proportion used for hot water [kWh]

Electricity

223,097

280,000 kWh

+ Kitchen & heating DHW in summer: 20,216*

+ 76,000 kWh used for hot water

41,141 kWh

76,000 kWh used for hot water

+ Kitchen & heating DHW in summer: 6.738 kWh* 85,802 kWh = 14,255 €

85,109 kWh = 12,269 €* (total = 23 % lighting, 40 % technology, 35% cooling and 1 % heating) 82,459 kWh = 13,032.65 € net of VAT

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Annex 2: Case studies selected as BPs and their main features. Name

Country / zone

Sector, zone and loop

Main features

Centre ‘ZASTITI ME’

Bosnia

Public Sector

Energy renovation of a public building

Sothern Europe Zone

Horizontal collectors

Horizontal Loop

Linked to existent radiators Electric heat pump Only heating mode

Geothermal closed loop system in primary school

Veneto

Public Sector

Energy Renovation of a public building

Southern Europe

Vertical collectors

Vertical Loop

Electric heat pump Integration with other renewable sources

Pipistrel Research & Development building

Slovenia

Industry e SME sector

New commercial/industrial building

Southern Europe

Electric heat pump

Vertical Loop + Horizontal Loop

Use of vertical and horizontal collectors, as seasonal energy storage. Use of free cooling, thanks to the storage Heating and cooling mode

Deep Foundation piles as source of energy. Settlement 15 may

Agricultural Centre

Slovenia

Puglia

Company + residential sector

Mini geothermal district heating: 3 blocks of flats, 1 office building

Southern Europe

Electric heat pump

Vertical Loop (foundation piles)

Energy piles

Public Sector

Energy renovation of a public building

Southern Europe

Vertical collectors

Vertical Loop

Gas absorption heat pump

Heating and cooling mode

Linked to existent radiators Low enthalpy geothermal closed loop plant with vertical probes for heating / cooling of apartment block

Teramo

Private sector

New block of flats

Southern Europe

Vertical collectors

Vertical closed loop

Electric heat pump High energy rating (A+) Heating and cooling mode

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University building of the Polytechnic Institute of Setubal

Portugal

Public Sector

Geo.Power Best Practice (BP by CRES)

Southern Europe

Energy renovation of an University building

Vertical closed loop

Electric heat pump Vertical collectors Low enthalpy geothermal closed loop plant with vertical probes for heating / cooling of single house

Ferrara

Private Sector Southern Europe Vertical closed loop Vertical collectors

Geo.Power Best Practice (BP by Province of Ferrara) New residential building High energy rating Electric heat pump Integration with other renewable energy sources

Greenhouse near Antwerp

Belgium

Industry sector

Geo.Power Best Practice (BP by VITO)

Central Europe

Experimental geothermal application on a greenhouse

Vertical Closed loop

Vertical collectors Gas absorption heat pump Hotel “Amalia”

Greece

Commercial sector

Geo.Power Best Practice (BP by CRES)

Southern Europe

Energy renovation of an hotel

Open loop

Open loop Electric heat pump

Ground source heat pump with borehole thermal energy storage (BTES) at headquarters INFRAX

Belgium

Commercial sector

Geo.Power Best Practice (BP by VITO)

Central Europe

New office building

Closed loop

High energy rating Vertical collectors Electric heat pump

“Peter Mahringer“ Private High School

Albania

Private sector

Two electric heat pumps: 2x90 kW

Sothern Europe

Open loop Geothermal energy for air conditioning of buildings (both heating and cooling) – San Lazzaro (BO) Row houses in San Giovanni in Persiceto (BO) – Italy Geothermal energy for air conditioning of buildings (both heating and cooling) – Cervia (RA) Europoint_Building at Podgorica

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Annex 3: Ground Source Heat Pumps demonstration cases in public and residential buildings utilizing GSHP in the Adriatic area. Masseria “Oasi le Cesine” (Apulia Region – Italy) Period of construction

Several: end of 1500 to end of 1700

Size [m2]

1.000

Materials

Rural building (masseria)

Type

Farm buildings at nature reserve

Energy data and objectives of the energy conversion: Heating plant

Fuel, electricity

Power [kW]

50

Thermal Energy rating [kWh/m2/y ]

126,2

for heating

76,4

for cooling

49,8

Renewable energy

0

GSHP system

Vertical

Absorption

Total energy data (thermal + electrical):

Pre-intervention

Post-intervention

Renewable energy production [kWh/y] Primary energy consumption [kWh/y] CO2 emissions [kg/y] Energy Costs [€/y]

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TECHNICAL INDUSTRIAL INSTITUTE (Province of Teramo – Italy) Period of construction

2005 (1^ lot) – 2009 (2^ lot)

Size [m2]

3.693

Materials

Reinforced concrete structure with infill into blocks of brick insulation and brick concrete floors with insulation of roofing panels of polystyrene

Type

School

Energy data and objectives of the energy conversion:

Heating plant

0

Power [kW]

0

Thermal Energy rating [kWh/m2/y ]

0

for heating

0

for cooling

0

Renewable energy

0

GSHP system

0

0

Total energy data (thermal + electrical):

Pre-intervention

Post-intervention

Renewable energy production [kWh/y] Primary energy consumption [kWh/y] CO2 emissions [kg/y] Energy Costs [€/y]

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“PJERINA VERBANAC” NURSERY EXTENSION (IRENA – Croatia) Period of construction

Construction underway

Size [m2]

973

Materials

25 cm brick building with reinforced concrete elements, well insulated (mineral wool – 12 cm on walls, 18 cm on roof, xps – 8 cm on floor)

Type

Nursery

Energy data and objectives of the energy conversion:

Heating plant

Building under construction – planned energy source for heating – geothermal and electric energy planned energy source for DHWP – geothermal, electric and possibility of solar(combined boiler with 3 input possibilities)

Power [kW]

Building under construction –18,8 kWh geothermal pump needed

Thermal Energy rating [kWh/m2/y ]

16,27

for heating

12,41

for cooling

3,86

Renewable energy

Building under construction – according to projections made in thermo technical system elaborate 78% of heating energy required will be produced from renewable sources (geothermal energy

GSHP system

Vertical

Electric

Total energy data (thermal + electrical):

Pre-intervention

Post-intervention

Renewable energy production [kWh/y] Primary energy consumption [kWh/y] CO2 emissions [kg/y] Energy Costs [€/y]

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HIGH SCHOOL “MARIE CURIE” (Province of Teramo – Italy) Period of construction

1989

Size [m2]

13.928

Materials

Reinforced concrete structure with infill into brick blocks and brickconcrete roofs

Type

School

Energy data and objectives of the energy conversion:

Heating plant

0

Power [kW]

0

Thermal Energy rating [kWh/m2/y ]

0

for heating

0

for cooling

0

Renewable energy

0

GSHP system

0 0

Total energy data (thermal + electrical):

Pre-intervention

Post-intervention

Renewable energy production [kWh/y] Primary energy consumption [kWh/y] CO2 emissions [kg/y] Energy Costs [€/y]

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IIS CIVITA – MONACO DI POMPOSA (Province of Ferrara – Italy) Period of construction

1970

Size [m2]

0

Materials

Reinforced concrete and infill masonry

Type

School

Energy data and objectives of the energy conversion:

Heating plant

Natural gas boilers and radiators

Power [kW]

3 plants: 581,5 / 300 / 813

Thermal Energy rating [kWh/m2/y ]

205

for heating

205

for cooling

0

Renewable energy

PV 10 kWp

GSHP system

Open loop Electric

Total energy data (thermal + electrical):

Pre-intervention

Post-intervention

Renewable energy production [kWh/y]

11,000

261,000

Primary energy consumption [kWh/y]

2,737,554

2,831,300

CO2 emissions [kg/y]

561,300

507,000

Energy Costs [€/y]

204,250

173,250

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KINDERGARTEN, STARCEVICA (LIR Bosnia and Herzegovina) Period of construction

1978

Size [m2]

175

Materials

Building has reinforced concrete frame structure with walls made of siporex blocks (lightweight autoclaved aerated concrete) without any insulation on facade walls

Type

Education, kindergarten

Energy data and objectives of the energy conversion:

Heating plant

Electrical boiler for heating of domestic hot water

Power [kW]

-

Thermal Energy rating [kWh/m2/y ] for heating

220

for cooling

-

Renewable energy

0

GSHP system

Vertical Absorption

Total energy data (thermal + electrical):

Pre-intervention

Post-intervention

Renewable energy production [kWh/y] Primary energy consumption [kWh/y] CO2 emissions [kg/y] Energy Costs [€/y]

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SILIVIJA STRAHIMIRA KRANJČEVIĆA 11 OPUZEN (County Opuzen) Period of construction

0

Size [m2]

2.000

Materials

Concrete, no insulation

Type

0

Energy data and objectives of the energy conversion:

Heating plant

Heating oil

Power [kW]

200+200 backup

Thermal Energy rating [kWh/m2/y ] for heating

105

for cooling

-

Renewable energy

25

GSHP system

Other Electric

Total energy data (thermal + electrical):

Pre-intervention

Post-intervention

Renewable energy production [kWh/y] Primary energy consumption [kWh/y] CO2 emissions [kg/y] Energy Costs [€/y]

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CULTURAL CENTRE (Municipality of Danilovgrad – Montenegro) Period of construction

1947/reconstructed in 1982

Size [m2]

517,65 (ground floor) + 517,65 (1stfloor)

Materials

Walls are made from stone with plaster and paint, without insulation

Type

Movie projections, exhibitions, theatre/cultural centre

Energy data and objectives of the energy conversion:

Heating plant

Electricity

Power [kW]

400

Thermal Energy rating [kWh/m2/y ]

0

for heating

0

for cooling

0

Renewable energy

No

GSHP system

0 0

Total energy data (thermal + electrical):

Pre-intervention

Post-intervention

Renewable energy production [kWh/y] Primary energy consumption [kWh/y] CO2 emissions [kg/y] Energy Costs [€/y]

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KINDERGARTEN ISMET SALIBRUÇAJ (Municipality of Shkodra) Period of construction

2014

Size [m2]

410

Materials

Masonry

Type

Kindergarten

Energy data and objectives of the energy conversion:

Heating plant

Electrical energy

Power [kW]

31680

Thermal Energy rating [kWh/m2/y ]

11,65

for heating

11,65

for cooling

0

Renewable energy

79,4% (6.516 kWh/31.680 kWh)

GSHP system

Open loop Electric

Total energy data (thermal + electrical):

Pre-intervention

Post-intervention

Renewable energy production [kWh/y] Primary energy consumption [kWh/y] CO2 emissions [kg/y] Energy Costs [€/y]

74

LEGEND PROJECT


Annex 4: Locations of sewer pipes, water supply network, gas network, heat energy network.

Figure 29. Location of sewer pipes (Public spatial data - http://portal.3-port.si/public/trimap/piran/javno/javaClient.3map?file=piran_web_plan_nusz).

Figure 30. Location of water supply network (Public spatial data - http://portal.3-port.si/public/trimap/piran/javno/javaClient.3map?file=piran_web_plan_nusz).

Pre-investment analysis for large Ground Source Heat Pump investments in Obalno-kraška region

75


Figure 31. Location of gas network and heat energy network (Public spatial data - http://portal.3-port.si/public/trimap/piran/javno/javaClient.3map?file=piran_web_plan_nusz).

Figure 32. Location of transport infrastructure (Public spatial data - http://portal.3-port.si/public/trimap/piran/javno/javaClient.3map?file=piran_web_plan_nusz).

76

LEGEND PROJECT


Annex 5: Working diagrams for selected GCHPs.

Pre-investment analysis for large Ground Source Heat Pump investments in Obalno-kraška region

77


78

LEGEND PROJECT


Pre-investment analysis for large Ground Source Heat Pump investments in Obalno-kraška region


Project partner Geological Survey of Slovenia DimiÄ?eva ulica 14 1000 Ljubljana Slovenia www.geo-zs.si


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