While big hydro power has fallen out of favour due to social and environmental costs, small hydro is a resource waiting to be tapped. Clean and reliable, it has few of the environmental consequences of large hydro, and there is still plenty of potential out there. Christine Lins and Maria Laguna report. Fast track for small hydro? A weir on the river Enns in Austria serves as a small hydro plant, generating 250 kW VIOREL MUNTEANU
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pproximately 70% of the earth’s surface is covered with water, a resource that has been exploited for many centuries. The use of hydro power has been characterized by continuous technical development, and it is currently the second most used renewable energy source in the world,just behind solid biomass.Hydro supplies the vast majority of renewable electricity, generating 16.6% of world supply and 92% of total renewable energy electricity (IEA, 2003).
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SMALL HYDRO POWER AROUND THE WORLD There is no international consensus on the definition of small hydro power (SHP). In China, it can refer to capacities of up to 25 MW, in India up to 15 MW, and in Sweden,‘small’ means up to 1.5 MW. However, a capacity of up to 10 MW total is becoming generally accepted by ESHA, the European Commission and UNIPEDE (International Union of Producers and Distributors of Electricity). Small-scale hydro power systems capture the power in flowing water and convert it to usable energy. Although the potential for small hydro power depends on the availability of suitable water flow, where the resource exists it can provide
Runaway potential Small hydro in Europe and beyond
clean, reliable electricity. A well designed small hydro power system can blend in with its surroundings and have minimal negative environmental impacts. SHP schemes are mainly runof-river with little or no reservoir impoundment. SHP plants combine the advantages of hydro power with those of decentralized power generation, without the disadvantages of large-scale installations. SHP is a clean, sustainable, efficient and secure renewable energy source. It has a huge, as yet largely untapped potential, which should enable it to make a significant contribution to future energy needs, offering a very good alternative to conventional sources of electricity not only in industrialized countries but also in developing ones. Asia, especially China, is set to become a leader in hydro electric generation. Present developments in Australia and New Zealand are focusing on small hydro power plants. Canada, a country with a long tradition in using hydro power, is developing small hydro as a replacement for expensive diesel generation in remote off-grid communities. Markets such as South America, the former Soviet Union and Africa also possess great untapped potential (Figure 1). Estimates of the world installed capacity of small hydro vary, partly due to the sizing definition. In 2000 the world
installed capacity of small hydro power was about 37 GW and in 2003 the total installed capacity was estimated at 56 GW (Eric Martinot, REW Sept–Oct 2004). All regions of the world are experiencing significant increases in small hydro capacity, with China again showing the largest increase.
SHP IN EUROPE Renewable Electricity Directive targets The trend towards SHP has been enhanced by the European Commission’s White Paper on renewable energy and by the EU Renewable Electricity Directive (RES-e Directive). Both give a clear signal that greater use of renewable energy is necessary to reduce society’s environmental impacts, ensure security of supply and create a sustainable energy system. In 1997 the European Commission’s paper on renewable energy sources COM (97) 599, 26.11.97 set the goal of doubling the share of renewable energy sources in the EU energy sector from 6% to 12% by 2010, which would bring renewables to represent around 22.1% of electricity generated. Projections for each renewable energy technology were made. For SHP this means the ambitious target of reaching by 2010 14 GW of installed capacity, generating 55 TWh of electricity.
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FIGURE 1. SHP installed in various regions
Targets for SHP The European Directive for the Promotion of the RES electricity in the Internal Market Directive 2001/77/EC follows up the White Paper on renewable sources of energy. It also constitutes an essential part of the package of measures needed to comply with the commitments made by the EU under the 1997 Kyoto Protocol on the reduction of greenhouse gas emissions. According to the RES-e Directive, renewable generators should provide 22% of electricity by 2010 in EU-15 and 11% in EU-10, the new Member States (Table 1). The RES-e Directive gives Member States a reason to look at SHP because it is the best proven of all renewable energy technologies. Of special interest for Europe, from both an economic and environmental point of view,is the high potential for upgrading and refurbishing of existing plants, since about 70% of the current installations are more than 40 years old.
SHP and the Water Framework Directive The European Water Framework Directive (WFD) is an environmental directive being currently implemented at national level.Together with the Network Natura 2000, it aims to encourage national environmental legislation on nature Eastern Europe has the greatest potential for SHP projects, like this one in Poland POLISH ACADEMY OF SCIENCE
Small hydro intake in Wales, UK
protection.This rigorous environmental framework guarantees the adequate integration of SHP with the natural environment. However, some inconsistencies in WFD terminology and its implementation may contradict the RES-e Directive, and may lead to loss of production at SHP plants. The targets of the RES-e Directive can never be reached in matters of SHP if there is no harmonization between the two Directives.The solution is in a more precise terminology, which makes the transposition of the WFD clear and predictable. Depending on how the WFD Directive is implemented, production losses could be of about 15%–20% in small hydro power production, preventing the European targets on Renewable Energy and the Kyoto commitments on CO2 reduction from being reached.
SHP plants in operation According to a recent report produced by ESHA’s Thematic Network on Small Hydropower, in the former EU-15 about 14,000 SHP plants are in operation, with an average size of 0.7 MW.There are around 2800 SHP plants installed in the new Member States and about 400 in the candidate countries (CC) respectively. The average size of these plants is 0.3 MW in EU-10 and 1.6 MW in EU-CC. Schemes in the EU-10 are small, only around half the size of the average in the EU-25.The situation in the candidate countries is the opposite, and most schemes are approximately twice as big as those in the EU-15.The SHP plants situated in the former EU-15 are also the oldest. New Member States and candidate countries have the highest share of young SHP plants, especially the candidate countries. According to Eurostat figures for 2002, Italy accounted for about 21% of the total SHP capacity installed in the EU-25, followed by France (17%) and Spain (16%). In the new Member States, both Poland and the Czech Republic had 2% of the total TABLE 1. Status and targets for renewables in Europe (%); targets according to the RES-e Directive Status, 1999 Targets, 2010 EU-15 13.9 22 EU-10 5.4 11.1 EU-25 12.9 21
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SMALL HYDRO Runaway potential
SHP IN FIGURES EU-15 • 33%: the renewable energy industry’s target for the contribution of renewable energy to electricity production by 2010 • 22.1%: the renewable electricity target set up by European Directive RES-e by 2010 • 14 GW: the amount of energy that SHP would need to produce to meet this target. This would generate 55 TWh of electricity per year • 19,600 GWh/year: the potential for new plants in the EU-15 • 5–15 Eurocents/kWh: average SHP electricity production cost • € 1200–3500/kW: average SHP investment cost • 14,488: number of SHP plants • 10 GW: installed capacity of the 14,488 SHP plants, equivalent to roughly 1.77% of total EU-15 capacity • 8.6%: contribution of SHP to total hydro capacity, producing 40,300 GWh. This means that SHP contributes 2% to total electricity generation • 700 kW: average installed capacity for an SHP plant • 6000: jobs in SHP (direct and indirect) in 2002
EU-25 SHP capacity and are the lions of the new EU Member States. From the candidate countries, Romania and Turkey represent about 25% and 15%, respectively, of the total SHP installed capacity in 2002 in both EU-10 and the candidate countries combined.
Remaining SHP potential More than 82% of all economically feasible potential has already been exploited in the former EU-15 with the remaining 18% amounting to some 20 TWh/year. In the new Member States and the candidate countries, this figure is around 26 TWh/year. The majority of this potential (roughly 80% or 19,300 GWh/year) is located in Turkey. Poland and Romania rank second, having indicated potential 6–10 times lower than that of Turkey. The third group is composed by the Czech Republic, Slovenia, Bulgaria and Slovakia. Small hydro plant in Slovenia EKOWATT
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EU-10 • 11%: demand for renewable electricity by 2010 • 2770: number of SHP plants • 820 MW: installed capacity from the 2770 plants, producing 2300 GWh/year of electricity. This would contribute to 0.6% of total electricity generation and 12.8% of the total hydro power production in EU-10 • 2.4–3.2 Eurocents/kWh: average SHP electricity production cost • € 1200–2200/kW: average SHP investment cost • 300 kW: the average installed capacity for an SHP plant • 4000 GWh/year: remaining SHP potential CO 2 reduction via small hydro power • 1 GWh supplies electricity for about 220 European households, avoiding the emissions of 480 tonnes of CO 2 • Average output of a 1 MW small hydro power plant in Austria is 5 GWh/year, enough for 1100 households • 5 GWh/year supplies 2200 households in a developing country Figures from ESHA and the Thematic Network on Small Hydropower 2004
SHP in the renewable energy mix Hydro power now accounts for about 84% of the electricity generated from renewable sources in Europe and for 13% of total electricity production in the EU-15. Electricity generation from SHP contributed about 2% to the total electricity generation in the EU-15 in 2001.About 9% of the RES electricity generation and 4% of the RES primary energy in the EU-15 were produced by SHP plants in 2001. This contribution was similar to wind but somewhat lower than biomass. At present, hydro power is a dominant source of energy in RES-e production in almost all countries. It accounts for approximately 4.6% of total hydro generation in the new EU Member States and candidate countries. None of the other renewable energy sources (wind, biomass or PV) is able to compete with small hydro power in these countries.
SHP economics and costs In general, large hydro electric plants have little difficulty in competing with conventional generation, but small hydro, especially the very small and the low-head plants, can normally only compete where allowances are made for the external costs associated with fossil fuels and nuclear power. The capital required for small hydro plants depends on the effective head, flow rate, geological and geographical features, continuity of water flow, equipment (such as turbines or generators) and civil engineering works. Making use of existing weirs,dams,storage reservoirs and ponds can significantly reduce both environmental impact and costs. Sites with low heads and high flows require a greater capital outlay, as larger civil engineering works and turbine machinery will be needed to handle the larger flow of water. If, however, the system can have a dual purpose – such as power generation and flood control,
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power generation and irrigation, power generation and drinking water production – the payback period can be shortened. Apart from the investment and production costs, the other principal cost element is operation and maintenance (O&M), including repairs and insurance, which can account from 1.5%–5.0% of investment costs. Both the production and investment costs differ considerably depending on the plant’s head height.
workers (around 1000). In addition, there are about 4000 people involved indirectly, including electricity producers. It can therefore be estimated that about 6000 employees are working – directly and indirectly – in the EU-15 SHP sector. Predictions by EREC (European Renewable Energy Council) suggest that European employment in the small hydro sector could potentially reach 15,000 and 28,000 for direct and indirect jobs respectively.
INDUSTRY STATUS
BENEFITS WORLDWIDE
Europe has maintained a leading position in the field of hydro power manufacturing ever since the technology started to develop 150 years ago. Very little equipment installed in European hydro power plants were sourced from outside Europe. One important reason for this dominance has been Europe’s strong domestic market. By developing technology and production methods in a fast-growing home market, European manufacturers have, with few exceptions, kept a leading edge compared with manufacturers from other parts of the world. Several manufacturers are active in small hydro in the European Union. Four major multinational companies dominate the market for larger turbines, but the market between 0.5–5.0 MW per site is more accessible to small companies. European companies have pioneered much of the technical development, and in recent years have dominated international contracts for small hydro power equipment and installations.
Looking to the future, there are good reasons to support small hydro power in Europe and worldwide. First and foremost, it is a source of renewable energy, which, if used on a small scale and handled sensitively, has few environmental risks. Increased use will help to reduce CO2 emissions and help countries to achieve their Kyoto obligations as well as to stave off global warming. Secondly,the depletion of oil and natural gas deposits will lead to higher generation costs for thermal plants, helping to improve the economics of SHP. It will also serve to enhance economic development and living standards, especially in remote areas with limited or no electricity. Rural communities have been able to attract new industries – mostly related to agriculture – owing to their ability to draw power from SHP stations. In countries such as South Africa, China, and Nepal, rapid SHP development has also boosted the development of local manufacturers to support these hydro power plants. In addition, the ability of SHP to be combined with water infrastructure projects will allow it to become a regular feature in developing countries as they overhaul their irrigation, water supply and sewerage systems. Furthermore, small hydro would enable countries to reduce their dependence on imported fuel, reducing costs and improving security. Finally, from a European point of view, continuing expansion of this industry can only be good as other parts of the world invest in European expertise and equipment.
EMPLOYMENT Employment in the EU-15 SHP sector is growing. Latest figures show that in 2002 about 2200 people were working directly in the small hydro power sector. This includes manufacturers (around 1200) plus research and consultancy TABLE 2. Investment and production costs of SHP plants in some EU Member States (2003). Source: ESHA 2004 Country Average SHP production Average O&M cost cost (Eurocents/kWh) (Eurocents/kWh) Spain 3.5–7 0.9 Austria 3.6–14.5 0.4 Sweden 4.0–5 1.4 Czech Republic 2.0–3 – Lithuania 2.5–3 – Poland 3 –
Maria Laguna is a Project Manager at the European Small Hydropower Association. Christine Lins is Secretary General at the European Small Hydropower Association. e-mail: laguna@esha.be To comment on this article or to see related features from our archive, go to www.renewable-energy-world.com and click the ‘Forum’ tab.
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