Passive Solar Design

Module E03 - Solar Design Project

The GreenHaus GROUP 10 ALEXIOS KOUFAKIS AMALIA VRANAKI ANTONIETTA CANTA KONSTANTINOS CHARALAMPIDIS

Contents 01 SITE ANALYSIS 3 01.1 01.2 01.3 01.4 01.5 01.6

The location Air quality Noise levels Property value Crime rate Public transportation

10 ADDITIONAL SYSTEMS 14 10.1 Artificial lighting and daylight harvesting sensors 10.2 Solar Panels and rain water collection

11 CONCLUSIONS 14

02 CLIMATE ANALYSIS 4 02.1 Macro-climate 02.2 Micro-climate

03.1 The family 03.2 Occupancy 03.3 Design targets

SHOEBOX ANALYSIS

ARCHITECTURAL CONCEPT

6

7

05.1 Function 05.2 Form

06 DESIGN PROCESS 8 06.1 Initial environmental strategies 06.2 Iterative process

07 FINAL DESIGN 10 07.1 Final environmental strategy 07.2 Final results

08

DAYLIGHT ANALYSIS

08.1 Tools and assumptions 08.2 Design evolution 08.3 Results

APPENDIX III: Architectural drawings

20

APPENDIX IV: Summary of environmental performance 32

04.1 Tools and assumptions 04.2 Results

05

APPENDIX I: References 15 APPENDIX II: 3D visualizations 16

03 DESIGN DATA 5

04

09 MATERIALS 13

12

APPENDIX V: Shoebox analysis

34

APPENDIX VI: IES-VE model specifications

37

APPENDIX VII: Daylight and artificial light analysis

40

01 Site analysis

SOLAR DESIGN PROJECT 2016 | GROUP 10 | THE GREENHAUS

01.1 THE LOCATION The chosen location is in the residential neighbourhood “Forest Hills”, which is situated in the upper north-west part of Washington, D.C. The capital of the United States of America has a population of around 670,000 people, presents several embassies and organizations’ headquarters but little industry (District Department of the Environment, 2014).

Very unhealthy

Unhealthy

Moderate

Good

Figure 1.1-.2: Location of the site on the city map

Figure 1.3: Daily values of five pollutants in Washington D.C. in 2015 (source: www.epa.gov/airquality/airdata)

01.2 AIR QUALITY The Air Quality Index (AQI) was developed by the United States Environmental Protection Agency (EPA) in order to quantify air quality, by assessing five pollutants, namely ground-level ozone, particulate matter, carbon monoxide, sulfur dioxide, and nitrogen dioxide (Airnow.gov, 2016).

The District of Columbia has little industry, so the pollutants are mostly associated with the public and private means of transportation and the air movement which brings pollutants from neighbouring states. In 2015, the Air Quality Index (AQI) indicates moderate and good air quality levels throughout the year with zero days of unhealthy or very unhealthy conditions (AQI>100 for more than 98% of time).

Although there are no available data for the Forest Hills area, its location away from the city centre and next to the Rock Creek Park means that the concentration of air pollutants will be even lower than the average for the area.

Figure 1.4: Daily average AQI Values in 2015 (source: www.epa.gov/airquality/airdata)

01.3 NOISE LEVELS Being a residential area away from highways, railroads, airports, construction areas, industrial and commercial buildings, the ambient noise levels are generally low: approximately 40dB average during day and night time (RentLingo, 2016; Howloud, 2016).

01.4 PROPERTY VALUE

Figure 1.5: Noise levels (source: howloud.com, 2016)

Figure 1.6: House prices (source: welovedc.com/heatmap)

Figure 1.7: Number of assaults (source: Apps.urban.org, 2016)

Figure 1.8: Number of robberies (source: Apps.urban.org, 2016)

The upper north-west part of Washington, D.C. is a prestigious and wealthy part of the city. Thus, it is significantly more expensive than the eastern part but less expensive than the central district (Welovedc.com, 2016).

01.5 CRIME RATE The area of “Forest Hills” has one of the lowest crime rates in the city. In 2015, reported aggravated assaults and robberies were less than 10 (Apps.urban.org, 2016).

01.6 PUBLIC TRANSPORTATION The site is located near the Connecticut Avenue and is served by the Red Line of the Washington Metro (Van Ness-UDC metro station) as well as several lines of the public bus service (Metrobus).

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02 Climate analysis

SOLAR DESIGN PROJECT 2016 | GROUP 10 | THE GREENHAUS

02.1 MACRO-CLIMATE Washington D.C. has a humid subtropical climate with 4 distinct seasons (Koeppen-geiger.vu-wien. ac.at, 2016). The climate analysis for Washington (Typical Meteorological Year 2 for Sterling- Washington Dulles, 39.0 latitude and -77.4 longitude) in Weather Tool provided the following results.

02.1.1

Wind

The prevailing winds are generally from the South throughout the year, except winter when they tend to prevail from Northwest. Southern and North-Western winds have the highest temperatures whereas North and North-Western are the coldest.

02.1.2

Sun path

The optimal orientation for Washington D.C. is 177.5째N. With this orientation, the total annual incident solar radiation is approximately 923 kWh/m2 and the average daily radiation is around 1.6 kWh/m2.

02.1.3

Psychrometric Chart

The psychrometric chart illustrates that ambient air is usually humid and either too cold or too hot.

The comfort zone, designed for sedentary activity, 20% glazing ratio, high insulation and average efficiency, shows that dehumidification, cooling and heating are required for the majority of the time. Passive solar heating, thermal mass, natural and night ventilation are the most appropriate techniques to increase the comfort zone.

Figure 2.5: Stereographic projection of sun-path in Washington, D.C. (source: Weather Tool - Square One)

Figure 2.6: Optimum orientation in Washington, D.C. (source: Weather Tool - Square One)

02.2 MICRO-CLIMATE The site is located in a low-density residential area where the houses are built among the nature, surrounded by trees and fields. This aspect contributes to protect the site from environmental issues: the majority of the existing trees are deciduous species, meaning that they have dense leaves during summer and are bare in winter. Thus, they may DECIDUOUS TREES: help in the reduction of solar gains during summer, Platanus Orientalis Platanus Occidentalis while not affecting them during winter. As the Acer Circinatum trees are denser toward the South, they may Acer Glabrum Alnus Rubra also protect from the hot South wind prevailing in Alnus Sinuata Sitka Cornus Nuttallii summer, and be a shelter from the noise coming Prunus Emarginata from the road.

SUMMER

AUTUMN

SPRING

WINTER

Figure 2.1-2-3-4: Micro-climate analysis for the site

Figure 2.7: Psychrometric chart for Washington, D.C., showing the comfort zone for human occupation (source: Weather Tool - Square One)

Figure 2.8: Psychrometric chart for Washington, D.C., showing the effects of several passive design techniques on the comfort zone(source: Weather Tool Square One)

Figure 2.9-10-11: Frequency and temperature of the prevailing winds in Washington D.C. respectively for the entire year, winter and summer (source: Weather Tool Square One)

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03 Design data

SOLAR DESIGN PROJECT 2016 | GROUP 10 | THE GREENHAUS Jake, 36: home-working journalist for National Geographic

Shanon, 3: she stays home with her grandmother during weekdays

03.1 THE FAMILY The family consists of four members; two parents and their two children. There is also a grandmother who visits the family in a daily basis -except weekends- in order to take care of the youngest child.

The father is a journalist and needs a space to work in the house.

They all have environmental concerns and therefore, they were interested in a bioclimatic design and passive strategies for their home.

Figure 3.1: The family

22 20 19

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7

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9

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3

1 child d2 chil ndmother a r g

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22 21 20

2

fathehrer mot

6

7

19

1

5

6 8

18

12

4

1 child d2 chil ndmother a r g

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5

10

bedrooms

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16

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Artificial lighting

Although no specific requirements exist for artificial lighting in domestic environments, the recommendations from various standards and guides - summarised in Table 3.2 - were considered (EN 12464-1, 2011; SLL 2013; IESNA, 2000).

24

3

living room-greenhouse studio

Daylight

The standard BS 8206-2:2008 provided guidance on the daylight factor targets. The recommendations from various other sources were considered (SLL, 2013; SLL, 2014; IESNA, 2000). Their proposed values are shown in Table 3.2. Although they are associated with good daylighting design practice, the design aimed to significantly surpass them.

03.3.3

er mothher fat

WEEKENDS

2

4

adaptive method (ASHRAE, 2013). In order to provide a comfortable internal environment for all the family members, the 90% acceptability limits were selected instead of the 80% ones. Moreover, the literature was reviewed to investigate how age affects thermal comfort and it was found that the comfort range for the elderly lies in higher temperatures compared to younger people (Hoof and Hensen, 2006; Hwang and Chen, 2010). Thus, the lower limit of the comfort range in the main area and kitchen - where the grandmother would spend the majority of her time - was increased by 1째C. For accurate outdoor temperatures, the weather data from 1981 to 2010 were examined (Weather.gov, 2016). An average temperature for each season was calculated and used as the prevailing mean outdoor temperature.

The final comfort range is presented in Table 3.1.

1

13

23

12

14

Temperature

The thermal comfort range was based on the ASHRAE Standard 55

03.3.2

24

12

WEEK DAYS

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03.3 DESIGN TARGETS 03.3.1

Donnah, 65: wants to grow her own vegetables and plants

16

The occupancy patterns were specified according to the daily schedule of each family member, both for weekdays and weekends (Figure 3.2).

Carol, 6: she goes to primary school and loves to play outside

Emily, 35: a working mother, needs a space in contact with nature to relax. She loves cooking, and gardening, like her mother

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03.2 OCCUPANCY

kitchen Figure 3.2: Occupancy profile

Table 3.2: Design targets for daylight and artificial lighting Table 3.1: Comfort ranges for each season

Room

Kitchen, living room Bedroom, corridor, bathroom, toilet, home office

Comfort range (oC) Winter Summer Midseason 18-22 21-25 24-28 17-22 20-25 23-28

Room

Kitchen Living room Bedroom Bathroom Corridor Home office

Daylight factor (%) 2 1.5 1 5

Illuminance (lux) 300 250 250 250 250 400

Limiting glare rating 19

Uniformity of illuminance on task area 0.7

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04 Shoebox analysis 04.1 TOOLS AND ASSUMPTIONS The shoebox was analysed in IES-VE and ReluxPro. Located in Washington, D.C., it was 5x5m, 2.4m high. The internal dry resultant temperature and the average daylight factor were the examined variables to determine the performance of each model.

04.2 RESULTS Detailed graphs and tables are presented in Appendix V. The conclusions are presented below.

04.2.1

Thermal mass

The heavyweight structure (230kJ/m2K) leads to smaller internal temperature fluctuation and less extreme values during winter and summer, compared to a lightweight structure (60kJ/m2.K). It also creates a time lag between the peak external temperature and the peak internal temperature.

Having lightweight walls in some parts of the building (e.g. North, South) reduces the overall thermal mass and has the same drawbacks as mentioned above.

04.2.2

SOLAR DESIGN PROJECT 2016 | GROUP 10 | THE GREENHAUS

04.2.7

Trombe wall/Greenhouse

A Trombe wall 0.5x5m and a greenhouse 1.5x5m have been simulated. Both solutions facing South resulted in higher temperatures during winter in contrast to other orientations. The greenhouse-home area ratio analysis concluded that the smallest the ratio, the higher the internal temperature during winter. A sensitivity analysis on the effect of opening the greenhouse glazing on its internal temperature showed that continuously opening just 5% of the total glazing percentage can lower its maximum internal temperature by 41% during winter.

04.2.8

Building shape

During winter, the indoor temperature is slightly higher when the shoebox has a rectangular shape compared to an L-shape with the same internal area and glazing percentage. No meaningful difference was observed during summer between the two building shapes.

Insulation

Insulation (100mm with R=0.02W/mK) in the internal side of the building significantly lowers its thermal mass, making it almost lightweight. This problem does not occur when using external insulation.

Increasing the insulation thickness reduces the thermal transmittance which attenuates the extreme temperature variations.

04.2.3

Air tightness

Air permeability acts like additional ventilation. Thus, an airtight building (0.25 ACH infiltration) will have more comfortable internal conditions during winter but less desirable during summer, compared to one with a high leakage rate (1 ACH infiltration).

04.2.4

Glazing

Modifying the glazing percentage significantly affects the solar gains and heat losses. Increasing the glazing area in the West and East results in higher internal temperatures during summer and mid-season and almost the same thermal conditions during winter. On the contrary, raising the glazing percentage in the South increases the internal temperature by almost the same percentage throughout the year. Raising the glazing-to-wall ratio in the North faรงade considerably increases the internal temperature during summer but slightly reduces it during winter. Finally, shadings and window coatings which reduce the solar transmittance lower the internal temperatures all year long.

04.2.5

Solar gains and daylight

According to the IES-VE SunCast simulations, the South faรงade receives around 1100kWh/m2a of solar energy compared to almost 500kWh/m2a of the North faรงade and 1500kWh/m2a of the flat roof.

According to ReluxPro, placing the openings higher increases the daylight factor.

04.2.6

Natural ventilation

During summer, stack ventilation is the optimum strategy to prevent overheating, compared to singlesided and cross ventilation.

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05 Architectural concept

5.8. Design Progression

RESPECTING THE FOOTPRINT AND SOLAR ENVELOPE _CLIENT’S BRIEF

form

The architectural concept was progressed in parallel to the shoebox, IES and Relux analysis (Figure 5.5), trying to make the best out of the limited space and finally create a functional and aesthetically pleasing house. The spaces needed are the common areas, i.e. living room, kitchen, dining room and utility spaces, 2 bedrooms and a working space for the father (studio).

10m

05.1 FUNCTION

+

Taking into account the results from the shoebox analysis, a rectangular form was proposed, with the longest side facing South. This simple shape is the most appropriate in order to reduce heat losses through the building fabric -minimum exposed surface area- compared to a more complex shape, and it also provides a simple and functional plan.

One of the main ideas was to create a protective shell able to diffuse the extreme environmental conditions of Washington, and at the same time provide the feeling of an external space, so that the family members can feel that they are outside, regardless of external conditions. For the above reasons, the main plan was divided in half, creating a greenhouse; a buffer zone between the internal and external spaces (Figure 5.2). The greenhouse functions as an extension of the main area during winter, and as a protected, shaded external space during summer. It is also the ideal space for the gardening activities, relaxation and a place for the children to play, as it consists a lively, comfortable and pleasing environment. The middle wall is made of a high thermal mass material and functions as a second facade; it can also be transformed according to the external conditions (Figure 5.7).

After considering the needs of each family member, as well as the best space distribution in terms of environmental performance and ergonomy, the distribution shown in Figure 5.5 was proposed: The main area is in direct contact with the greenhouse and the spaces can be extendend within it. The studio and the bedrooms are placed at the upper levels, as they need more privacy, but the visual contact with the greenhouse will be kept to the maximum possible by the existence of internal balconies or large openings (Figure 5.7).

In terms of section, the house was divided in different floors depending on the privacy levels (Figure 5.4). Thus, in the ground floor the living room, kitchen and dining room were placed, in the second floor the two bedrooms and in the third floor the working studio.

6.5m

CREATING THE PITCHED ROOF _ARCHITECTURAL CONCEPT

=

ADDING THE GREENHOUSE _ARCHITECTURAL CONCEPT _SHOEBOX ANALYSIS

function

protected interior a

5.2.a. Rigid, transformable spaces

greenhouse-buffer zone 5.4.Internal balconies: views, contact with nature

5.2.b. Linear space in direct contact with the winter garden

private direct contact visual contact

bedroom 1

studio

bedroom 2

a

FINDING THE RIGHT PROPORTIONS _MAXIMIZING INTERNAL SPACE _OPTIMIZING THE GREENHOUSE AS INDICATED FROM SHOEBOX ANALYSIS

semi-private

common spaces 5.3.Differentiation of levels according to their privacy

ADDING THE BOXES _ADDITIONAL INTERNAL SPACE _INTERNAL BALCONIES _ADDITIONAL SHADING

a-x

a+x

MAIN AREA living room

kitchen

ADDING OPENINGS, BALCONY FOR THE STUDIO

external blinds

greenhouse

5.5.Space distribution-initial

second facade: high thermal mass separates interior - greenhouse glazing

05.2 FORM As far as the form is concerned, the adjacent existing buildings played a major role in the design process. Most of them are examples of the typical American house -pitched roof, timber framed walls (Figure 5.1), and that was something to be respected. Subsequently, the traditional “pitched-roof” shape was kept in order to keep the cohesion of the urban tissue, but by developing a new, more creative and environmental approach.

6.3m

5.1.Typical American house: pitched roof house, timber frame walls

WC living room

dining room

OPENINGS MODIFICATION _IES VE SIMULATION | OPTIMIZE THERMAL PERFORMANCE _RELUX SIMULATION | OPTIMIZE DAYLIGHT FACTORS

high thermal mass

kitchen

bedroom

studio bedroom WC

greenhouse Ground floor 5.6. Space distribution-final

1st and 2nd level

balconies additional shading glazing 5.7. Axonometry of final structure and shape

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06 Design process

SOLAR DESIGN PROJECT 2016 | GROUP 10 | THE GREENHAUS

06.1 INITIAL ENVIRONMENTAL STRATEGIES The main idea for the environmental design is the greenhouse: a changing space between the interior and exterior which behaves as a buffer and transforms according to the outside weather. It is designed as a rectangular space which lays along the house toward the South, with completely glazed walls and roof and a system of movable shadings.

SUMMER - DAY

WINTER - DAY

During winter, the shadings are opened and the glazed surface can absorb the maximum solar radiation: the greenhouse becomes a heat storage which transfers its heat to the interior space through the windows on the intermediate wall, which can be totally opened to maximise the heat exchange. The space can also be used as a winter garden. During summer, the glazings are totally opened and the shadings close, so that the buffer space becomes a shaded patio which contributes to minimise the solar gains into the house and can be used as a leisure outdoor space. The deciduous trees on the South side of the house contribute to shade the building during summer, without reducing the solar gains during winter.

For the ventilation strategy, cross ventilation was the main component. In summer, the South warm wind is obstructed from the trees, so the North colder wind could be used to introduce fresh air into the house. During winter, instead, the ventilation rate is reduced to the minimum in order to minimise the heat losses, and the necessary supply of fresh air occurs through the greenhouse, which helps in warming up the air before it enters the building.

SUMMER - NIGHT

WINTER - NIGHT

Figure 6.1: Initial environmental strategies

PERFORMANCES IN THE MAIN AREA % OF TIME WITHIN COMFORT RANGES AVERAGE CO2 LEVELS DURING OCCUPIED HOURS DURING OCCUPIED HOURS (PPM)

06.2 ITERATIVE PROCESS 06.2.1

06.2.2

Greenhouse

By adding the greenhouse on the South façade of the building, the heat from the incoming solar radiation is being trapped inside it. This aimed to warm the interior spaces during the winter and mid-season. The greenhouse was opened during summer to avoid overheating.

Without further changes in regards to the base case, the greenhouse significantly increased the indoor temperature. Nevertheless, the percentage of time in the comfort range in mid-season dropped to 5%. For the remaining time overheating occurred, pointing out the need of shading.

06.2.3

Greenhouse and windows shading

During winter a minimum amount of shading was provided from the wooden structure of the greenhouse. That amount was calculated and the greenhouse structure was modified in a way that the wooden blocks represented the actual shading. The additional shading decreased the thermal comfort by 16% during winter but increased it by 15% during mid-season. The overheating during summer was still the major concern at this stage. In order to reduce the indoor temperature, an initial shading profile was created for the windows facing south. Modifying the external shading with a 0.2 sky and ground diffuse transmission factor, the diffuse and diffuse ground-scattered solar radiation incident on the windows was significantly decreased. Thus, the overheating was brought down to half and the percentage of time in comfort range during summer was increased to 53%.

06.2.4

0% 14% 38%

Base Case

Setting as a starting point the model design on IES VE according to the initial architectural and environmental design, the performance analysis was launched. The base case included the design of the house without the greenhouse, in order to note the differences before and after its addition. With the windows continuously closed, the results indicated that only 25% of the annual occupied periods was within the comfort range. More specifically, the percentage of comfort range was 38% in winter, 14% during mid-season and 0% in summer. The aforementioned results refer only to the main area of the house. However, the thermal performance of the remaining areas follows the same pattern.

Single-sided ventilation

Apart from the design modifications that were made to optimize the thermal comfort during this stage, several ventilation strategies were developed to supply fresh air and lower the CO2 levels. It was noticed that the CO2 concentration during the occupied hours was above 3000ppm, especially in the bedrooms. After modulating the south-façade windows and setting 25% openable area for 2 hours during the afternoon, the CO2 levels dropped to around 1500ppm. However, it wasn’t possible to keep the thermal comfort inside the desirable targets (Graph VI.1a-b in Appendix VI), so it was obvious that more complex profiles were needed. They will be discussed at step 6 and 7.

IES MODEL SCREENSHOTS

summer

1344

mid season winter

0% 5% 61% 1344

53% 20% 45% 1344

59% 28% 26% 684

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SOLAR DESIGN PROJECT 2016 | GROUP 10 | THE GREENHAUS

06.2.5

Envelope improvements

At this stage, the percentage of hours within the comfort range was still low for winter and mid-season; therefore it was considered necessary to improve the building envelope. Firstly, the U- and g-value of the greenhouse windows were modified based on the PassivHaus standards (Pelsemakers, 2015), setting a window U-value at 1.1 W/m2K (1.6W/m2K before) and a g-value at 0.7 (0.35 before).

Consequently, the heat losses from the windows were decreased, allowing a higher amount of solar energy to pass through the windows. Secondly, the insulation conductivity was improved to 0.02W/mK, leading to a U-value of 0.13W/m2K for the external wall (0.23W/m2K before). For the South wall, the simulations demonstrated that not having any insulation increased the heat transfer between the building and the greenhouse, which was beneficial during winter and didn’t make a significant difference during summer. As a result of these changes, the percentage of comfort range was almost doubled in winter (49%) but only slightly increased in mid-season (35%).

06.2.6

89% 51% 80% 878

Stack ventilation, night-cooling and windows modulation

Apart from the single-sided ventilation that was described in step 4, stack ventilation was also employed in this project. Three top north windows were added in the circulation area and a hole was created between the two floors to represent the staircase. The formula that was assigned in these windows was the same with the windows in the living room and the kitchen and they were functioning only in summer and autumn. In winter, they were closed as the outdoor temperature was quite low. In spring, they were also closed as the overheating and the CO2 levels in both floors were efficiently controlled by the single-sided ventilation. However, it was noticed that during some occasions air was coming in from the top windows preventing the proper function of the stack effect. Even in that case, the windows operated in such a way that when the indoor temperature was outside a specific comfort range they would close. For summer, that range was between 25°C and 26°C and for autumn between 22°C and 24°C. Another new addition was night cooling. It was considered essential mainly during summer to reduce overheating. Different night cooling profiles were set in each room, where the windows would open when the indoor temperature was exceeding a specific setpoint, different for each season. Finally, the window profile in the main area changed once again by setting a higher temperature range before it would open, as the overheating in midseason was 46%. One step shy of the final model, the main area was over 90% within the comfort range for each season.

06.2.8

684

Windows and shading modulation

This iteration discusses the detailed design of the window and shading profiles that was developed through the performance analysis.

At first, mid-season was separated into spring and autumn and the annual profiles included four different profiles representing each season, instead of three. The main idea of the formulae was to keep the temperature inside the design targets as much as possible without increasing the CO2 levels. That means that the windows would open when the indoor temperature dropped below the lower limit or if it was higher than the upper limit, in order to warm up or cool down the interior spaces respectively. Otherwise, they would remain closed. A minimum amount of opening was also set in order to ventilate the room. It was noticed that in winter and mid-season, the greenhouse was functioning beneficially as its temperature was limited to such levels that enabled both cooling and heating. In summer, night-cooling was adopted as the main strategy and it will be discussed in step 7. As the overheating was still a great issue, several modifications were made in the greenhouse shading profiles. The new shading profiles were based on the definition of sunshine duration (solar radiation exceeding 120W/m2) from the World Meteorological Organization (WMO, 2008). The new shading profiles were operating from March until August so that the temperature inside the greenhouse could be more effectively controlled, even during midseason (the final formulae of each profile are on Appendix VI). The results showed that these changes greatly improved the percentage of thermal comfort for the entire year, which reached 80% in winter, 51% in mid-season and 89.4% in summer.

06.2.7

58% 35% 49%

Final Adjustments

Minor modifications to the final model were performed in this stage, considering both the temperature and the CO2 levels. Firstly, a new formula was set in the greenhouse shading profile in order to operate when the solar irradiation was greater than 90W/m2 instead of 120W/m2 to further reduce overheating. Below that value, it did not make any significant difference. Secondly, small changes occurred in the window profile opening setpoints. Thirdly, doors were added in the upper floor. They were set to open whenever the CO2 levels were higher than 1300ppm. These final adjustments led to the results that are displayed next. In the main area, the percentage of thermal comfort during the occupied hours reached 99.5% during winter and 97.4% during both mid-season and summer.

93% 95% 91% 901

97% 97% 99% 798

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07 Final design

SOLAR DESIGN PROJECT 2016 | GROUP 10 | THE GREENHAUS

07.1 FINAL ENVIRONMENTAL STRATEGY

Greenhouse windows closed

Thermal mass effect heat absorption and reduction in temperature fluctuation

Shadings closed

5% opening for fresh air and overheating reduction

heat absorption and reduction in temperature fluctuation

heat storage and reduction in temperature fluctuation

North openings closed

Top North windows closed

to minimize solar gains

Thermal mass effect

Thermal mass effect

to minimize heat losses

unless needed for ventilation

Shadings opened to maximize solar gains

Internal windows closed

Trickle ventilation for fresh air provision

according to the internal and external temperatures

Trickle ventilation for fresh air provision

Greenhouse windows closed

Internal openings opened to maximize the heat trasfer from the greenhouse

to reduce overheating and increase wind driven ventilation

to control solar gains

Top North windows modulating according to the internal and external temperatures

Internal windows modulating

unless needed for ventilation

Greenhouse windows opened

Shadings closed

5% opening when needed for fresh air and overheating reduction

Plants contribution to cool the air

SUMMER - DAY

WINTER - DAY

Thermal mass effect

MID SEASON - DAY

& Night ventilation

releasing the thermal energy

cooling the thermal mass by discharging the accumulated heat

Thermal mass effect

Thermal mass effect

releasing the stored heat

releasing the stored heat

Top North windows opened South windows opened

except when overcooling occurs

except when overcooling occurs

Greenhouse windows opened to reduce overheating and increase wind driven ventilation

SUMMER - NIGHT

Greenhouse windows closed 5% opening for fresh air

North openings closed

Internal windows modulating

Top North windows modulating

to minimize heat losses

according to the internal and external temperatures

according to the internal and external temperatures

Trickle ventilation for fresh air provision

External structure

South openings closed

provides security for night ventilation to keep the heat inside

WINTER - NIGHT

Greenhouse windows closed

Trickle ventilation for fresh air provision

5% opening when needed for fresh air and overheating reduction

MID SEASON - NIGHT

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SOLAR DESIGN PROJECT 2016 | GROUP 10 | THE GREENHAUS

07.2 FINAL RESULTS The final results are displayed in graphs 7.1-2 and Appendix IV. The passive design managed to achieve exceptional levels of thermal comfort throughout the year. More specifically, all areas managed to stay within the comfort range for at least 97% of the occupied time. The kitchen and the main area turned out to be the most challenging spaces, due to the increased occupied hours, the high internal gains and the big south openings. The design also aimed to provide acceptable ventilation, even during the coldest days of winter. Thus, almost 95% of the time the CO2 concentration was less than 1500ppm for all the rooms. As seen in graph 7.2, the two bedrooms were the most demanding spaces as they were occupied mostly during night, when the outdoor temperatures were generally below the comfort range. With a clever design of the doors and window openings, the CO2 levels in the bedrooms exceeded the 2000ppm threshold less than 3% of the occupied time. All the profiles for windows and shadings are included in Appendix VI.

07.2.1

Graph 7.1

Graph 7.2

Competition week

The competition week was set between Oct, 6th and Oct, 12th. This time period contained several challenges, as the external temperature fluctuated significantly between 2 and 27°C, with the majority of the time being below the assigned comfort range. Moreover, the comfort range was especially narrow (2.2°C) making the control of the environmental strategies even more difficult. However, with an intricate design of the window and shading modulation for both the house and the winter-garden, all areas were 100% of the occupied time within the comfort zone. The controls for this specific week were designed from scratch, separately for each room. It is worth noting though that this result was achieved at the expense of CO2 levels, which were generally higher than the annual average. The results are displayed in graph 7.3.

07.2.2

Heating and cooling loads

The heating and cooling loads were calculated from IES-VE to specify the additional energy, required to achieve the design targets, for both the entire year and the competition week. A main system with proper heating and cooling set points was assigned to the rooms, operating only during the occupied hours. This was done in order to avoid unnecessary energy consumption. The need of heating during the winter and especially in February was quite high compared to the other seasons; however, there was a small amount of required cooling even in winter, which is justified by the minor overheating during that period (the details of the overheating and overcooling for each season are displayed in the Appendix VI). Furthermore, in mid-season and in summer the heating loads were lower but not eliminated, as again some overcooling occurred. The monthly loads are shown in graph 7.4. The maximum values of the cooling loads were noticed on May and on September, because the mid season profiles were not optimized for occasional extreme temperatures. The final annual space heating demand was calculated at 4kWh/m2 and the cooling demand at 0.5kWh/m2. The space heating demand was almost 4 times less than the maximum heating demand according to the Passivhaus standard. For the competition week, there was no extra energy required as the percentage of the hours within the comfort range was 100% for each room.

07.2.3

Graph 7.3

Graph 7.4

Computational Fluid Dynamics (CFD) analysis

A computational fluid dynamics analysis in MicroFlo was performed to visualise the velocity/ temperature vectors and contours. The analysis focused on the heat transfer between the wintergarden and the house interior during winter. The assumptions are presented in Appendix VI. The boundary conditions of the January 10th, 12:00am were imported. Figure 7.1 shows the temperature contours and velocity vectors (between 0.05m/s to 0.3m/s) and figure 7.2 presents the velocity contours. It is obvious that the temperature inside the greenhouse is higher than the house interior, reaching 23°C when the external temperature is close to 3°C. The openings are introducing warm air inside the house which enable it to retain a temperature of almost 22°C.

Figure 7.1: Air temperature contours and velocity vectors on January 10th, 12:00am

Figure 7.2: Air velocity contours on January 10th, 12:00am

11

08 Daylight analysis

SOLAR DESIGN PROJECT 2016 | GROUP 10 | THE GREENHAUS

08.1 TOOLS AND ASSUMPTIONS The ReluxPro software was used for the daylight simulations. The following assumptions were made: • The height of the reference plane was 0.8m and its distance to the internal walls was 0.5m. The task area was directly in front of the observer with a 0.5x0.5m measuring area; • The floor had beech wood with a 45.8% reflectivity, the ceiling white matt gypsum plaster with 80% reflectivity and the walls white matt gypsum plaster with 70% reflectivity. The doors had 80% reflectivity; • The North windows were triple glazed with 75% transmittance. The South ones were double glazed with 80% transmittance.

• The 3D objects (chairs, desks, sofas, appliances, etc.) had no effect on the measured results (“design objects”); • The simulations were performed with average indirect fraction precision under overcast sky- according to CIE- on 21/01, 11:00am; • The top floor was simulated with a flat roof, instead of a sloped one, due to software limitations. All rooms on the top floor were simulated separately with the actual sloped roof to ensure that the differences in the presented results were negligible; • The shadings from the greenhouse were not taken into account.

08.2 DESIGN EVOLUTION The percentage of glazing and the positioning of windows changed several times during the design process, as shown in graph 8.1. The northern façade had no openings initially but in the end an intricate design of multiple openings was adopted, which provided useful daylight over the staircase, the circulation area, the home office, the kitchen and the ground floor toilet. The East and West façades had originally a small percentage of glazing which was removed eventually to reduce the heat losses and support the architectural design.

Finally, the openings in the South were fine-tuned according to computer simulation results from ReluxPro and IES VE to maximise daylight penetration and minimise overheating.

The daylight design of the home office was the most challenging, as it required an average DF higher than 5% and openings which would not cause overheating and glare during the day. The initial idea of a big opening in the South was replaced by a north-facing window and skylight to benefit from the diffused lighting during the biggest part of the day and the minimal direct sunlight. This increased the uniformity of illuminance and reduced overheating and potential glare.

Graph 8.1

08.3 RESULTS The achieved daylight factors by far surpassed the recommendations from BS 8206-2, as shown in graph 8.2. In the home office and kitchen, artificial lighting is not generally needed as the daylight factors are higher than 5% (SLL, 2013). The north-facing openings in the home office resulted in a 0.78 uniformity of illuminance in the task area, exceeding the 0.7 recommendation (SLL, 2013). The illuminance distribution from daylight under overcast sky is shown in figure 8.1-2-3. It is clear that all internal spaces receive an abundance of natural light. Detailed printouts of the daylight analysis are presented in Appendix VII.

Graph 8.2

Figure 8.1-2-3: 3D pseudo colours representation of the illuminance under overcast sky for the ground floor, first floor and home office on 21/01, 11:00 am.

12

09 Materials

SOLAR DESIGN PROJECT 2016 | GROUP 10 | THE GREENHAUS

The selection of construction materials and technologies has considered the following main aspects: • Architectural appearance and aesthetics • Coherence with the local building methods • Suitabilty with the function of the element (performances) • Buildability (ease of construction and maintenance) • Environmental sustainability (embodied energy) Particular attention has been given to the high thermal mass material for the vertical and horizontal main structure: the multi-criteria analysis has involved the most common construction materials, such as bricks, stone and concrete, as well as more innovative solutions, namely rammed earth and water walls. Table 9.1 shows the volumetric heat capacity of each solution and the embodied energy (Mirò et al., 2015). Beside this objective values, also architectural appeal and coherence with the construction tradition of the location have been considered. Therefore, concrete has been selected because it combines relatively high volumetric heat capacity and low embodied energy with a high architectural appeal and ease of construction and maintenance.

Thermal Mass: Volumetric heat capacity (KJ/m³k)

Embodied Energy (MJ/kg)

Brick

1,360

3

Rammed earth

1,673

0.45

Sandstone

1,800

1

Concrete

2,060

0.75

Water walls

4,186

≈0

Table 9.1: Comparison of high thermal mass materials (Mirò et al., 2015).

A link with the local building tradition is represented by the external structure which is made of timber columns and beams reproducing the typical model of the traditional American house; this choice is also based on the consideration that wood is a local material, that means lower carbon footprint related to transportation.

The flexibility of the South façade is the main feature of the design in terms of both architecture and environmental strategies; therefore, the systems have been designed for the maximum operability and flexibility. The two main systems (windows and shading devices) have been defined in order to be operable independently and define different configurations depending on the external weather, as shown in Figure 9.1. The shadings consist of sliding wooden louvred shutters; the windows are timber-framed double-glazed, with a folding system for the vertical walls of the greenhouse and sliding and rotating system for the roof (Figure 9.2). Timber-framed windows have been used for the openings on the main walls as well, double glazed on the South wall and triple glazed on the North in order to minimize the heat losses in the coldest wall.

04

01 02

03

03

05

01

Figure 9.1: External summer and winter view

01

Main external structure | Timber

02

Fixed louvres | Timber

03

Sliding louvred shutters | Timber

04

Folding/tilt windows | Timber frame, double glazing

05

Folding windows | Timber frame, double glazing

Figure 9.1: Detail of the changing façade

13

10 Additional systems

SOLAR DESIGN PROJECT 2016 | GROUP 10 | THE GREENHAUS

Solar PV Panels 30° inclined

10.1 ARTIFICIAL LIGHTING AND DAYLIGHT HARVESTING SENSORS The artificial lighting installation for the whole house was designed to investigate the minimum lighting gains and power density for lighting that could be achieved by using energy efficient luminaires and LED lamps. Although secondary and accent lighting was not considered, this study aims to show the benefits of an artificial lighting design working in harmony with the daylight design.

The ReluxPro simulation showed that the total lighting power per area was 5.2W/m2 and 5.4W/m2 for the ground floor and the top floor respectively. The unified glare rating in the home office was less than 15 for two observers in critical positions. The ReluxEnergy simulations concluded that by using daylight harvesting sensors (dimming, switching on, switching off) in the areas that are occupied during the day (home office, main area and kitchen) the energy savings can be up to 28% for the main area and kitchen and 26% for the home office, as shown in graph 10.1. Detailed assumptions, equipment and software printouts are presented in Appendix VI.

Daylight sensors

Solar PV Panels 90° inclined Rain water collection tank

Figure 10.1: Additional systems

Graph 10.1

10.2 SOLAR PANELS AND RAIN WATER COLLECTION

Total energy associated with lighting, equipment and PV panels 160

Annual Energy associated with lighting, equipment and PV panels 1800

1000

120

Energy (kWh)

1400 1200

140

1651

1600

Energy (kWh)

In order to meet the lighting and equipment demand, a PV system was designed and modelled on IES VE. The system consists of thin film solar panels with a 7% efficiency which can be implemented on the fixed modules of the shading devices, thanks to the flexibility of the film. The total area of the panels was 17m2 (12m2 on the vertical part of the greenhouse structure and 5m2 with 30° inclination installed on the greenhouse roof), providing an annual energy of 916 kWh and covering a 35.4% of the total lighting and equipment consumption. The PV generated electricity along with the lighting and equipment consumption are displayed in graphs 10.2 and 10.3. A percentage of the surface utilised for solar PV panels (e.g. 3m2) could be used for thermal solar panels, in order to provide hot water.

A rain water collection system can be implemented to provide water for the WCs and the irrigation.

915.7

933.1

800

100 80 60 40

600

20

400 200

0 Jan JanF

0 PV

Lighting

Feb eb

Mar MarA

Apr pr

May MayJ

Jun un

Jul JulA

Aug ug

Sep SepO

Oct ct

Nov NovD

Dec ec

Equipment PV

Lighting

Equipment

11 Conclusions

Graph 10.2

The project achieved the aim of designing a sustainable house that combines architecture, affordability and buildability. The local building traditions have been adapted to bioclimatic architecture rules, achieving a final building which is perfectly integrated in the local context and respects the environmental issues.

Cost-effective materials have been chosen and extreme solutions were avoided in order to guarantee affordability and ease of realization.

These strategies fulfilled their goal as the thermal comfort targets were achieved more than 97% of the time. That was obtained through the detailed modelling and simulation of the building, using complex profiles for openings and shadings in each season. In real life that strict adaptability to the external conditions would be made possible only through a Building Management System. However, manual control by the occupants could still guarantee high levels of thermal comfort, thanks to the flexibility of the systems.

The participation of the occupants is critical in the design of the building and their needs must be taken into account: for example, an automatic system that controls the internal doors opening to provide better indoor air quality might lead to occupants dissatisfaction.

All passive solar design strategies have been employed in order to achieve maximum thermal and visual comfort with the minimum energy consumption. Namely: • ORIENTATION: the main facade was oriented toward the South in order to take advantage from the solar gains in winter and easily reduce their contribution in summer; • GLAZINGS AND SHADINGS: modular and movable panels have been used for both glazing and shading in order to obtain the best combination for each season; • THERMAL MASS: high thermal mass materials have been used to reduce the temperature fluctuation and provide a time-lag between the peak external and internal temperature; • INSULATION: insulation has been accurately designed to reduce the heat losses but enable the heat transfer between the greenhouse and the interior space, with attention to thermal bridges; • VENTILATION: single sided and stack ventilation have been designed according to the prevailing winds, in order to provide fresh air and passively cool the building, together with night-purge ventilation; • ZONING: the internal zones have been arranged according to the orientation of the building and similarities in design targets, in order to minimize the heating and cooling demand. The occupational patterns and the level of privacy required in each room have been also considered.

Graph 10.3

The main limitations are associated with the software used; the most important are the following: • The internal conditions of adjacent rooms (e.g. greenhouse) could not be used in the formula to control the openings. Although this option exists, it was not functioning properly.

• There is a positive correlation between the calculation time-step and the heating/cooling loads.

• The combination of sophisticated window modulation profiles and main system did not work as expected, as the system was often turned on when not needed.

• The CFD application in IES-VE was unable to properly simulate the air flow from non-rectangular and custom windows. Sometimes, an error regarding imbalanced airflows was generated, although they should have been equal.

• Complex geometries (especially for roof) could not be designed in ReluxPro. This study does not consider several factors that could be studied in detail in the future. For example, the cost analysis of such a project was not researched, so some of the proposals might not be cost-effective. A detailed Life Cycle Assessment would provide insight on potential changes and improvements over the final design. Finally, the use of specialised software for the computational fluid dynamics analysis could give a clearer view of the heat transfer between the rooms.

14

Appendix I: References

SOLAR DESIGN PROJECT 2016 | GROUP 10 | THE GREENHAUS

Airnow.gov, 2016. AirNow. [online] Available at: https://airnow.gov/ [Accessed 19 Mar. 2016].

American National Standards Institute, 2013. ASHRAE Standard 55-2013. Thermal environmental conditions for human occupancy.

Anderson, J., 2015. Embodied Carbon & EPDs [online]. Available at: http://www.greenspec.co.uk/building-design/embodied-energy/#ice [Accessed January 23, 2016].

Apps.urban.org, 2016. [online] Available at: http://apps.urban.org/features/ourchangingcity/dc-public-safety/index.html [Accessed 19 Mar. 2016].

Australian Government. YourHome: Australia’s guide to environmentally sustainable homes. [online] Available at: www.yourhome.gov.au/passive-design/thermal-mass [Accessed January 23, 2016].

BS 8206-2:2008, 2008. Lighting for Building. Code of Practice for Daylighting BS EN 12464-1:2011, 2011. Light and lighting. Lighting of work places. Indoor work places.

Circular Ecology. (2016). Embodied Energy and Embodied Carbon. [online] Available at: http://www.circularecology.com/embodied-energy-and-carbon-footprint-database. html#.VursDuLJzIU [Accessed 17 Mar. 2016].

District Department of the Environment, 2014. District of Columbia’s Ambient Air Quality Trends Report.

Epa.gov, 2016. AQI Plot | AirData | US EPA. [online] Available at: http://www3.epa.gov/airquality/airdata/ad_viz_plotaqi.html [Accessed 19 Mar. 2016].

Hoof, J.V., Hensen, J.L.M., 2006. Thermal comfort and older adults. Gerontechnology 4. doi:10.4017/gt.2006.04.04.006.00 Howloud, 2016. Howloud - Mapping the World of Sound. [online] Available at: http://howloud.com/ [Accessed 19 Mar. 2016].

Hwang, R., Chen, C., 2010. Field study on behaviors and adaptation of elderly people and their thermal comfort requirements in residential environments. Indoor Air 20, 235–245. doi:10.1111/j.1600-0668.2010.00649.x Koeppen-geiger.vu-wien.ac.at, 2016. World Maps of Köppen-Geiger climate classification. [online] Available at: http://koeppen-geiger.vu-wien.ac.at/ [Accessed 19 Mar. 2016].

Miró, L., Oró, E., Boer, D., Cabeza, L. F., 2015. Embodied energy in thermal energy storage (TES) systems for high temperature applications. Applied Energy, 137, pp.793–799 [online]. Available at: http://www.sciencedirect.com/science/article/pii/S0306261914006448 [Accessed January 23, 2016].

Pelsmakers, S., 2015. The environmental design pocketbook, 2nd edition. RIBA Publishing, London.

Rea, M.S., Illuminating Engineering Society of North America, 2000. The IESNA lighting handbook : reference & application / Mark S. Rea editor-in-chief., 9th ed. ed.

Illuminating Engineering Society of North America, New York, NY. RentLingo, 2016. (Heatmap) RentLingo Noise Index. [online] Available at: http://www.rentlingo.com/noise-index?latitude=38.9500389&longitude=-77.05924299999998 [Accessed 19 Mar. 2016].

Rgees.com. (2016). Phase Change Material (PCM) I Inorganic Salt Hydrates. [online] Available at: http://www.rgees.com/products.php [Accessed 17 Mar. 2016].

Society of Light and Lighting, 2013. Code for Lighting.

Society of Light and Lighting, 2014. Lighting guide 10: Daylighting - A Guide for Designers: Lighting for the Built Environment.

Weather.gov, 2016. [online] Available at: http://www.weather.gov/media/lwx/climate/dcatemps.pdf [Accessed 14 Mar. 2016].

Welovedc.com, 2016. Washington, DC housing rental prices. [online] Available at: http://welovedc.com/heatmap/ [Accessed 19 Mar. 2016].

World Meteorological Organisation, 2008. Guide to Meteorological Instruments and Methods of Observation. WMO-No. 8, 7th edition.

15

Appendix II: 3D visualizations

SOLAR DESIGN PROJECT 2016 | GROUP 10 | THE GREENHAUS

Figure II.1. View from the interior

16

SOLAR DESIGN PROJECT 2016 | GROUP 10 | THE GREENHAUS

Figure II.2. Rendered section

17

SOLAR DESIGN PROJECT 2016 | GROUP 10 | THE GREENHAUS

Figure II.3. Winter night view

18

SOLAR DESIGN PROJECT 2016 | GROUP 10 | THE GREENHAUS

Section A-A’

Section B-B’

West Elevation

South Elevation without the external structure

19

SOLAR DESIGN PROJECT 2016 | GROUP 10 | THE GREENHAUS

Appendix III: Architectural drawings FOOTPRINT LIMIT 800 ft2 = 74.3 m2

Private zone

Bedroom 1 10.25 m2

Studio 7.30 m2

Required Semiprivate zone

Total footprint (m2) Total conditioned floor area (m ) 2

Bedroom 2 9.75 m2

Public zone

Height (m) Width (m)

Bedroom 1 10.25 m2

Studio 7.30 m2

Toilet 1.55 m2

FOOTPRINT LIMIT 800 ft2 = 74.3 m2

Length (m)

74.3

74

41.8

74.85

≤ 6.25

6.25

≤ 20.40

6.60

≤ 25

11.20

Table II.1: Compliance with the House Sizing rules Service zone

Bedroom 2 9.75 m2 FIRST FLOOR | 1:100

Buffer zone

Actual

Service room 0.90 m2

Service room Toilet 0.90 m2 1.55 m2 Main Area 34 m2

SOLAR ENVELOPE - HEIGHT 20.5 ft = 6.25 m

Main Area 34 m2

0

1

3

6m

0.00

GROUND FLOOR | 1:100

0

1

0

3

1

2.5

5m

THE GREEN-HAUS PASSIVE SOLAR DESIGN PROJECT

6m

DRAWING

COMPLIANCE WITH SIZING RULES

SCALE

1:100

0.00

0

1

2.5

5m

20

SOLAR DESIGN PROJECT 2016 | GROUP 10 | THE GREENHAUS

A

B 11.20

2.65

0.20

2.45

0.20

2.45

2.65

0.20

0.20

0.20 0.10

0.20

h=3.30m

C

C' 4.15

4.15

h=2.40m

0.20

1.15

1.90

0.85

6.05

6.60

0.00

0.30

1.40

2.50

2.35

0.40

2.95

1.00

0.30

11.20

A'

B'

THE GREEN-HAUS PASSIVE SOLAR DESIGN PROJECT

0

1

2.5

5m

DRAWING

GROUND FLOOR | PLAN

SCALE

1:50 21

SOLAR DESIGN PROJECT 2016 | GROUP 10 | THE GREENHAUS

A

B 11.20 0.20

2.45

2.45

0.20

0.20

2.65

0.10

0.20

2.65

0.20

0.20

+2.60 h=2.95m

C

C'

+3.20

0.20

1.10

2.00

0.85

6.05

6.60

4.15

4.15

h=2.05m

0.30

2.35

3.90

0.40

2.95

1.00

0.30

11.20

A'

B'

THE GREEN-HAUS PASSIVE SOLAR DESIGN PROJECT

0

1

2.5

5m

DRAWING

FIRST FLOOR | PLAN

SCALE

1:50 22

SOLAR DESIGN PROJECT 2016 | GROUP 10 | THE GREENHAUS

+6.25

+3.20

0.00

0

0

1

1

2.5

2.5

5m

5m

THE GREEN-HAUS 0.00 PASSIVE SOLAR DESIGN PROJECT DRAWING

SECTION A-A’

SCALE

1:50 23

SOLAR DESIGN PROJECT 2016 | GROUP 10 | THE GREENHAUS

+6.25

+2.60

0.00

0

0

1

1

2.5

2.5

5m

5m

THE GREEN-HAUS 0.00 PASSIVE SOLAR DESIGN PROJECT DRAWING

SECTION B-B’

SCALE

1:50 24

SOLAR DESIGN PROJECT 2016 | GROUP 10 | THE GREENHAUS

+3.20 +2.60

0.00

0.30 0.35

3.20

0.45

0.70 0.10

2.00

0.10

3.35

0.35 0.30

11.20

THE GREEN-HAUS 0.00 SOLAR DESIGN PROJECT PASSIVE

0

1

2.5

5m

DRAWING

SECTION C-C’

SCALE

1:50 25

SOLAR DESIGN PROJECT 2016 | GROUP 10 | THE GREENHAUS

0.00

0

0

1

1

2.5

2.5

5m

5m

THE GREEN-HAUS 0.00PASSIVE SOLAR DESIGN PROJECT DRAWING

SOUTH ELEVATION

SCALE

1:50 26

SOLAR DESIGN PROJECT 2016 | GROUP 10 | THE GREENHAUS

0.00

0

0

1

1

2.5

2.5

5m

5m

THE GREEN-HAUS 0.00PASSIVE SOLAR DESIGN PROJECT DRAWING

NORTH ELEVATION

SCALE

1:50 27

SOLAR DESIGN PROJECT 2016 | GROUP 10 | THE GREENHAUS

0

1

2.5

5m

0.00

2.5

5m

THE GREEN-HAUS PASSIVE SOLAR DESIGN PROJECT

0.00

DRAWING

SOUTH & NORTH ELEVATION - UNCOVERED

SCALE

1:50 28

SOLAR DESIGN PROJECT 2016 | GROUP 10 | THE GREENHAUS

0.00

1

2.5

5m

0

1

THE GREEN-HAUS 0.00SOLAR DESIGN PROJECT PASSIVE

2.5

5m

DRAWING

WEST ELEVATION OPENED

SCALE

1:50 29

SOLAR DESIGN PROJECT 2016 | GROUP 10 | THE GREENHAUS

0.00

1

2.5

THE GREEN-HAUS 0.00SOLAR DESIGN PROJECT PASSIVE

5m

0

1

2.5

5m

DRAWING

WEST ELEVATION CLOSED

SCALE

1:50 30

0 0

0.5 0.5

Gravel - 400mm

XPS insulation - 100mm

Concrete slab - 200mm

1 1

Concrete wall 300mm

Window support Timber - 100mm Secondary structure Timber - 150mm

Concrete floor 250mm

Screed 30mm

Wooden floor 20mm

Mineral wool insulation 100mm

Folding window Timber frame - 60mm Double glazing - 28mm

Sliding louvred shutter Timber - 50mm

Main structure Timber - 200mm

Window support Timber - 100mm

Fiberglass insulation 30mm

Main structure Timber - 200mm

Timber frame - 60mm Double glazing - 28mm

Sliding/tilt window

Sliding louvred shutter Timber - 50mm

2m 2m

SOLAR DESIGN PROJECT 2016 | GROUP 10 | THE GREENHAUS

THE GREEN-HAUS PASSIVE SOLAR DESIGN PROJECT

DRAWING SOUTH FACADE | DETAIL

SCALE 1:20 31

Appendix IV: Summary of environmental performance

SOLAR DESIGN PROJECT 2016 | GROUP 10 | THE GREENHAUS

32

SOLAR DESIGN PROJECT 2016 | GROUP 10 | THE GREENHAUS

33

Appendix V: Shoebox analysis

SOLAR DESIGN PROJECT 2016 | GROUP 10 | THE GREENHAUS

34

SOLAR DESIGN PROJECT 2016 | GROUP 10 | THE GREENHAUS

35

SOLAR DESIGN PROJECT 2016 | GROUP 10 | THE GREENHAUS

36

Toilet

3.2

Appendix VI: IES-VE model specifications TABLE VI.1: Construction Materials

TABLE VI.2: Construction Properties

Layer Outer Pane Cavity (argon) Inner pane Outer Pane Cavity (argon) Inner pane Cavity (argon) Inner pane External insulation Reinforced concrete Chipboard flooring Plaster Insulation Reinforced concrete Cast concrete (LW) Sand Membrane Cast concrete (LW) Insulation Reinforced concrete

Glazing (South, greenhouse)

Glazing (North)

Floor

Walls

Roof

Thickness (mm) 6 16 6 6 16 6 16 6 130

Conductivity (W/mK) 1.06 1.06 1.06 1.06 1.06 0.02

Specific heat capacity (J/kgK)

1000

Resistance (m2K/W) 0.01 0.73 0.01 0.01 0.73 0.01 0.73 0.01 6.5

200 15 15 145

2.30 0.13 0.50 0.02

1000 1600 1000 1030

0.09 0.12 0.03 7.25

200 30 30 5 50 120

2.30 0.38 0.35 1.00 0.38 0.02

1000 1000 840 1000 1000 1450

0.09 0.08 0.09 0.01 0.13 5

200

2.30

1000

0.09

-

Transmittance 0.78 0.78 0.41 0.78 0.78

Element Glazing (South, greenhouse) Glazing (North) Ground floor Roof External wall Greenhouse structure

70

45

SOLAR DESIGN PROJECT 2016 | GROUP 10 | THE GREENHAUS 6.2 0.1* 75 55

Circulation area * According to NCM profiles

Element

0.1*

Total UValue (W/m2K)

Total gvalue

Thermal mass (kJ/m2K)

1.08 0.80 0.15 0.13 0.13 0.60

0.72 0.37 -

208 230 230 59

-

TABLE VI. 3: Internal Gains

Occupants Latent Heat Gains (W/P)

Lighting Sensible Gains (W/m²)

Equipment Sensible Gains (W/m²)

Equipment Latent Gains (W/m²)

Room

Plan area (m²)

People (No)

Occupants Sensible Heat Gains (W/P)

Main area

24.5

5

70

45

5.6

3.9

0

Kitchen

15.5

5

70

45

8.0

20.6

9.7

Home office

8.0

1

75

55

6.0

19.8

0

Master Bedroom

11.7

2

70

45

6.5

2.9

0.7

Kids Bedroom

10.6

2

70

45

6.5

2.9

0.7

Toilet

3.2

0.1*

70

45

10.5

1.6

0

6.2

0.1*

75

55

3.0

1.6

0

Circulation area * According to NCM profiles

Element

Total UValue (W/m2K)

Total gvalue

Thermal mass (kJ/m2K)

37

SOLAR DESIGN PROJECT 2016 | GROUP 10 | THE GREENHAUS TABLE VI.4: Main area daily profiles Time 12pm-8am 8am-8pm

8pm-12pm

Time 12pm-9am 9am-12pm

Time 12pm-9am 9am-12pm Time 12pm-9am 9am-12pm

Time 12pm-9am 9am-12pm

Winter Main Area Formula closed if the indoor temperature is greater than 21°C and the outdoor OR if it is lower than 19°C and the outdoor, the window will open 50%, otherwise a constant opening of 2% is maintained for fresh air if the indoor temperature is greater than 21°C and the outdoor OR if it is lower than 19°C and the outdoor, the window will open 50%, otherwise a constant opening of 4% is maintained for fresh air Spring Main Area Formula closed if the indoor temperature is greater than 21°C and the outdoor OR if it is lower than 19°C and the outdoor, the window will open 50%, otherwise a constant opening of 1% is maintained for fresh air Summer Main Area Formula if the indoor temperature is greater than 24.5°C, the window will open 25%, otherwise it will remain closed if the indoor temperature is greater than 26°C and the outdoor OR if it is lower than 25°C and the outdoor, the window will open 50% Autumn Main Area Formula if the indoor temperature is greater than 22.5°C, the window will open 25%, otherwise it will remain closed if the indoor temperature is greater than 24°C and the outdoor OR if it is lower than 22°C and the outdoor, the window will open 50% otherwise it will remain closed Competition Week Main Area Formula if the indoor temperature is greater than 23.5°C, the window will open 25%, otherwise it will remain closed if the indoor temperature is greater than 24°C and the outdoor OR if it is lower than 23°C and the outdoor, the window will open 50%, otherwise a constant opening of 1% is maintained for fresh air

TABLE VI.5: Bedroom daily profiles Time 12pm-8am 8am-12pm

Time 12pm-9am 9am-12pm

Time 12pm-9am 9am-12pm

Time 12pm-9am 9am-12pm

Time 12pm-9am 9am-12pm

Winter Bedroom 1 Formula if the indoor temperature is lower than 17°C, the window will remain closed, otherwise it steadily increases from 1.5% to 4% to maintain fresh air if the indoor temperature is greater than 22°C and the outdoor OR if it is lower than 19°C and the outdoor, the window will open 50%, otherwise it will remain closed Spring Bedroom 1 Formula if the indoor temperature is greater than 22.5°C, the window will open 25%, otherwise it will remain closed if the indoor temperature is greater than 23°C and the outdoor OR if it is lower than 21°C and the outdoor, the window will open 50%, otherwise it will remain closed Summer Bedroom 1 Formula if the indoor temperature is greater than 24°C, the window will open 25%, otherwise it will remain closed if the indoor temperature is greater than 26°C and the outdoor OR if it is lower than 24°C and the outdoor, the window will open 50%, otherwise it will remain closed Autumn Bedroom 1 Formula if the indoor temperature is greater than 22.5°C, the window will open 25%, otherwise it will remain closed if the indoor temperature is greater than 23°C and the outdoor OR if it is lower than 21°C and the outdoor, the window will open 50%, otherwise it will remain closed Competition Week Bedroom 1 Formula if the indoor temperature is greater than 23.5°C, the window will open 25%, otherwise it will remain closed if the indoor temperature is greater than 24°C and the outdoor OR if it is lower than 22.5°C and the outdoor, the window will open 50%, otherwise it will remain closed

TABLE VI.7: Greenhouse window profiles

TABLE VI.6: Home office daily profiles Time 24 hours Time

Winter Home office (North façade windows) Formula closed Winter Home office (South façade trickle) Formula

12pm-9am

closed

9am-9pm

50% open

9pm-12am

closed

Time

Spring Home office (North façade windows) Formula if the indoor temperature is greater than 22°C, the window will open 25%, otherwise it will remain closed if the indoor temperature is greater than 23°C and the outdoor OR if it is lower than 21°C and the outdoor, the window will open 50%, otherwise it will remain closed Spring Home office (South façade trickle) Formula

12pm-9am

closed

9am-9pm

if the indoor temperature is lower than 24.5°C, the window will open 50% otherwise it will remain closed

9pm-12am

closed

Time 12pm-9am 9am-12pm

Time

Summer Home office (North façade windows) Formula if the indoor temperature is greater than 23.5°C, the window will open 50%, otherwise will remain closed if the indoor temperature is greater than 24°C and the outdoor OR if it is lower than 23°C and the outdoor, the window will open 50%, otherwise it will remain closed Summer Home office (South façade trickle) Formula

12pm-9am

closed

9am-9pm

if the indoor temperature is lower than 27.5°C, the window will open 50% otherwise it will remain closed

9pm-12am

closed

Time 12pm-9am 9am-12pm

Time 24 hours Time 24 hours Time 24 hours Time 24 hours Time 24 hours

TABLE VI.8: Shading profiles

24 hours Time 24 hours

Time 24 hours

Time 24 hours

Time

Time 12pm-9am

closed

9am-9pm

if the indoor temperature is lower than 23.5°C, the window will open 50% otherwise it will remain closed

9pm-12am

closed

Time 12pm-9am

Time

Competition Week Home office (North façade windows) Formula if the indoor temperature is greater than 23.5°C, the window will open 25%, otherwise it will remain closed if the indoor temperature is greater than 24°C and the outdoor OR if it is lower than 22.5°C and the outdoor, the window will open 50%, otherwise it will remain closed Competition Week Home office (South façade trickle) Formula

12pm-9am

closed

9am-9pm

if the indoor temperature is greater than 22.5 and lower than 24°C, the window will open 50% otherwise it will remain closed

12pm-9am

9pm-12am

closed

9am-12pm

12pm-9am 9am-12pm

Time 12pm-9am 9am-12pm

Winter Shading Formula

Time

Autumn Home office (North façade windows) Formula if the indoor temperature is greater than 23.5°C, the window will open 40%, otherwise will remain closed if the indoor temperature is greater than 23°C and the outdoor OR if it is lower than 21°C and the outdoor, the window will open 50%, otherwise it will remain closed Autumn home office (South façade trickle) Formula

Time

Winter Greenhouse glazing Formula if the indoor temperature is greater than 25°C, a 5% of the total area will open, otherwise it will remain closed Spring Greenhouse glazing Formula if the indoor temperature is greater than 27°C, a 5% of the total area will open, otherwise it will remain closed Summer Greenhouse glazing Formula the greenhouse has been removed Autumn Greenhouse glazing Formula if the indoor temperature is greater than 23°C, a 5% of the total area will open, otherwise it will remain closed Competition Week Greenhouse glazing Formula if the indoor temperature is greater than 26°C, a 5% of the total area will open, otherwise it will remain closed

24 hours

No shading needed during the winter Spring Shading Formula If the outdoor temperature is greater than 15.5°C and the solar irradiance exceeds a value of 90W/m2 , shading with 0.2 sky and ground diffuse transmission factor will be provided Summer Shading Formula If the outdoor temperature is greater than 14°C and the solar irradiance exceeds a value of 90W/m2 , shading with 0.2 sky and ground diffuse transmission factor will be provided Autumn Shading Formula If the outdoor temperature is greater than 15.5°C and the solar irradiance exceeds a value of 90W/m2 , shading with 0.2 sky and ground diffuse transmission factor will be provided Competition Week Shading Formula If the outdoor temperature is greater than 15.5°C and the solar irradiance exceeds a value of 90W/m2 , shading with 0.2 sky and ground diffuse transmission factor will be provided

TABLE VI.9: Top North windows Time 24 hours Time 24 hours

9am-12pm Time 12pm-9am 9am-12pm Time

Winter Top North Windows Formula Closed Spring Top North Windows Formula Closed Summer Top North Windows Formula if the indoor temperature is greater than 24.5°C, the windows will open 50%, otherwise it will remain closed if the indoor temperature is greater than 26°C and the outdoor OR if it is lower than 25°C and the outdoor, the window will open 50%, otherwise they will remain closed Autumn Top North Windows Formula if the indoor temperature is greater than 22.5°C, the windows will open 50%, otherwise they will remain closed if the indoor temperature is greater than 24°C and the outdoor OR if it is lower than 22°C and the outdoor, the window will open 50%, otherwise they will remain closed Competition Week Top North Windows Formula if the indoor temperature is greater than 23.5°C, the windows will open 50%, otherwise they will remain closed if the indoor temperature is greater than 24°C and the outdoor OR if it is lower than 23°C and the outdoor, the window will open 50%, otherwise they will remain closed

38

SOLAR DESIGN PROJECT 2016 | GROUP 10 | THE GREENHAUS TABLE VI.10: Percentages inside and outside comfort zone

Winter

Spring

Summer

Autumn

Room Overcooling (%)

Within comfort zone (%)

Overcooling (%)

Within comfort zone (%)

Main Area

0.5

99.5

Kitchen

1.2

Overcooling (%)

Within comfort zone (%)

0

0.5

97.6

98.8

0

1.4

0

99.2

0.8

Bedroom 1

1.6

98.4

Bedroom 2

0.7

98

Overcooling (%)

Within comfort zone (%)

1.9

1.3

97.4

1.3

0.2

97.1

2.7

95.6

3

1.1

96.2

2.7

0.8

97

2.2

0

98

2

0

99.1

0.9

0

98.1

1.9

0

1.1

98.9

0

0.1

99.9

0

0

100

0

1.3

0.1

99.7

0.2

0

100

0

0

99.9

0.1

Table x. Parameters of utilization profile for ReluxEnergy calculations GRAPH(DIN VI.1a,b: Impact on CO2 levels and temperature after single-sided ventilation: There is a negative correlation between CO2 and temperature levels.

18599)

TABLE VI.11: Annual percentages inside and outside comfort zone

Annual Dry Resultant Temperature during occupied hours

Room Overcooling (%)

Annual operating hours Day (h) 0.6 Annual operating hours Night (h) Maintenance value1.1 Illuminance Kitchen (lx) Height of reference 0.0 plane Reduction factor task area Bedroom Relative 1 0.7 absence Reduction factor for building Bedroom 2 0.2 operation time Main Area

Ground

Home

Withinfloor comfort zone (%) office

5096 97.9 0 25096.9

2543 0 400

0.8098.6 0.92 0.3099.3 0.7

0.8 0.84 0.1 0.7

99.4

TableVI.12: x. Assumptions forthethe Computational Fluid Dynamics TABLE Assumptions for Computational Fluid Dynamic analysis Maximum cell aspect ratio Grid spacing (m) Grid line merge tolerance (m) Discretization scheme Turbulence model Surface heat transfer Number of iterations Windows Minimum opening dimension (m) Minimum opening flow (m3/s) Boundary conditions

1.5 2.0 1.4 0.0 0.4

analysis

Value 18:1 0 .1 0.01m hybrid k-e Software-calculated 150 Top-opening 0.05 0.0001 Jan 10th, 12:00am

39

Appendix VII: Daylight and artificial light analysis

SOLAR DESIGN PROJECT 2016 | GROUP 10 | THE GREENHAUS

40

SOLAR DESIGN PROJECT 2016 | GROUP 10 | THE GREENHAUS

41

SOLAR DESIGN PROJECT 2016 | GROUP 10 | THE GREENHAUS

42

SOLAR DESIGN PROJECT 2016 | GROUP 10 | THE GREENHAUS

43

SOLAR DESIGN PROJECT 2016 | GROUP 10 | THE GREENHAUS

Object Installation Project number Date

: : : Home : 09.02.2016

Top floor - artificial light analysis Summary, Top floor - artificial light analysis Result overview, Work space [m] 0.0

N

-0.5 -1.0 -1.5 -2.0 -2.5 -3.0 -3.5 -4.0 -4.5

0

Illuminance [lx]

1

50

2

3

100

4

5

6

150

7

200

8

9

250

General Calculation algorithm used Height of evaluation surface Maintenance factor

Average indirect fraction 1.55 m 0.80

Total luminous flux of all lamps Total power Total power per area (41.22 m²)

20000 lm 221.4 W 5.37 W/m²

Illuminance Average illuminance Minimum illuminance Maximum illuminance Uniformity Uo Diversity Ud

Eav Emin Emax Emin/Em Emin/Emax

[m]

300

423 lx 279 lx 653 lx 1:1.52 (0.66) 1:2.34 (0.43)

Type No.\Make 1

2

4

13

Philips Lighting Order No. : Luminaire name : BCS680 W7L122 1xLED24/840 LIN-PC Equipment : 1 x LED24/840/- / 2200 lm Order No. Luminaire name Equipment

: : DN460B 1xLED11S/840 C : 1 x LED11S/840/- / 1200 lm

Final.rdf

44

SOLAR DESIGN PROJECT 2016 | GROUP 10 | THE GREENHAUS

Object Installation Project number Date

Object Installation Project number Date

: : : Home : 09.02.2016

: : : Home : 09.02.2016

Ground floor - artificial light analysis Summary, Top floor - artificial light analysis

Summary, Ground floor - artificial light analysis

Result overview, Bedroom 1

Result overview, Living room

[m] 0.0 -0.5

-0.5

-1.0

-1.0

-1.5

-1.5

-2.0

-2.0

-2.5

-2.5

-3.0

-3.0

-3.5

-3.5

-4.0

-4.0

-4.5

-4.5

0

Illuminance [lx]

1

50

2

3

100

4

5

6

150

7

200

8

9

250

General Calculation algorithm used Height of evaluation surface Maintenance factor

Average indirect fraction 0.75 m 0.80

Total luminous flux of all lamps Total power Total power per area (41.22 m²)

20000 lm 221.4 W 5.37 W/m²

Illuminance Average illuminance Minimum illuminance Maximum illuminance Uniformity Uo Diversity Ud

Eav Emin Emax Emin/Em Emin/Emax

265 lx 181 lx 324 lx 1:1.46 (0.68) 1:1.79 (0.56)

Type No.\Make 1

2

4

13

Final.rdf

[m] 0.0

N

Philips Lighting Order No. : Luminaire name : BCS680 W7L122 1xLED24/840 LIN-PC Equipment : 1 x LED24/840/- / 2200 lm Order No. Luminaire name Equipment

N

0

[m]

300

Illuminance [lx]

1

50

2

3

100

4

150

5

6

7

200

8

9

250

General Calculation algorithm used Height of evaluation surface Height of luminaire plane Maintenance factor

Average indirect fraction 0.75 m 2.40 m 0.80

Total luminous flux of all lamps Total power Total power per area (40.27 m²)

16000 lm 208 W 5.16 W/m²

Illuminance Average illuminance Minimum illuminance Maximum illuminance Uniformity Uo Diversity Ud

Eav Emin Emax Emin/Em Emin/Emax

265 lx 168 lx 352 lx 1:1.57 (0.64) 1:2.1 (0.48)

Type No.\Make 12

: : DN460B 1xLED11S/840 C : 1 x LED11S/840/- / 1200 lm

Final.rdf

16

Philips Lighting Order No. : Luminaire name : DN135B D165 1xLED10S/840 Equipment : 1 x LED10S/840/- / 1000 lm

[m]

300

Table x. Parameters of utilization profile for ReluxEnerg TABLE VII.1: Parameters of utilization profile for 18599) calculations (DIN 18599) ReluxEnergy

Annual operating hours Day (h) Annual operating hours Night (h) Maintenance value Illuminance (lx) Height of reference plane Reduction factor task area Relative absence Reduction factor for building operation time

Ground floor 5096 0 250

Home office 2543 0 400

0.80 0.92 0.30 0.7

0.8 0.84 0.1 0.7

Table x. Assumptions for the Computational Fluid Dynamics analysis Maximum cell aspect ratio Grid spacing (m) Grid line merge tolerance (m) Discretization scheme Turbulence model Surface heat transfer Number of iterations Windows Minimum opening dimension (m) Minimum opening flow (m3/s)

Value 18:1 0 .1 0.01m hybrid k-e Software-calculated 150 Top-opening 0.05 0.0001

45