Passive Solar Design 3 key elements

1. Passive Solar Design3 key elements I. Maximizing Heat Collection in the Winter by means of a thermal mass. • Direct Solar Gain • Trombe Wall – indirect solar gain • Sunspace – combines both direct and indirect solar gain • Minimizing Heat Loss in the Winter • Preventing Overheating in the Summer

2. Thermal Mass-collection essential Any material in the home that absorbs and stores heat such as: concrete, brick, tile and other masonry materials. These materials absorb the sun’s energy and radiate it slowly into the house at night or on cloudy days. They are most effective when dark colored and are located in direct sunlight.

3. Direct solar gain - is radiant heat from the sun admitted directly into the living spaces, through south-facing windows, which is then absorbed by thermal mass.

5. A side view of a direct gain passive solar house(Design by Dennis Holloway, Architect)

6. Trombe Wall schematics • http://www.builditsolar.com/Projects/SpaceHeating/SolarWall/SolarWall.htm

7. Trombe Wall Essentials - indirect solar gain • Thermal MassSolid masonry wall works well . The more massive the better. • Selective Solar ExposureCollect in winter, protect in summer. Conceal with overhang that blocks summer sun but not winter sun. • Dark ColorPainted on or natural pigment, to absorb the sun's energy. • Glass InterfaceGlass lets through the optical energy from the sun. On an exterior wall, install double-pane (or even triple in very cold regions). • http://www.allanstime.com/SolarHome/Trombe_Wall/index.html

8. Passive Solar Residence for Gerald and Betsy Loffredo,Lyons, Colorado, 1979 One of the largest residential Trombe walls ever built. The Trombe wall provides 90% of the required space heating in this residence. The sunspace "crystal" in the front of the house provides vegetable year-round This trombe wall covers the whole side of the house http://www.dennisrhollowayarchitect.com/html/Loffredo.html

9. Trombe wall –with partial window shown from the inside and the outside http://www.aspencore.org/sitepages/pid67.php

10. Trombe wall-without window “…I painted the uninsulated plastered masonry wall dark green, attached a flat 1x3 frame with masonry screws and foam from a can, then added 1 layer of Dynaglas clear corrugated polycarbonate greenhouse glazing with corrugated foam strips on the vertical edges…” YO, check out my wall! http://www.builditsolar.com/Projects/SpaceHeating/nicksthrombe.htm

11. Sunspaces-use a combination of direct and indirect solar gain Sunlight entering the sunspace is absorbed by a thermal mass. Heat is brought into the house by means of conduction through a shared mass wall in the rear of the sunspace, or by vents that permit the air between the sunspace and living space to be exchanged by convection.

12. II. Protection from heat loss The heat you collect isn’t much good to you if you can’t hold onto it! • Insulation: R35 in walls, R50 in attics • Landscape – to create wind blocks • Careful room placement • Sloping land (berms) and roof lines

13. Berms • Earth Sheltering:achieve a low profile that provides insulation and energy savings. • cold winter winds just blow right over the house N http://www.sunterrahomes.com/homedesignconcepts.asp

14. Landscaping-as part of your design A windbreak on the northwest side can shield the home from prevailing winter winds. During the summer, tall deciduous trees planted close to the home shade the roof. Broad, shorter trees on the west side block afternoon solar heat. ' ' ' http://www.builditsolar.com/Projects/Cooling/Shading/EB%20Landscaping%20for%20energy%20efficiency.pdf

15. III. Preventing Overheating – a good solar design allows you to collect a lot of energy…but you don’t want it in the summer!! There are a variety of things that can be used to prevent over heating…. http://www.builditsolar.com/Projects/Cooling/passive_cooling.htm#Shading

16. Use of Overhangs – allows the sun to enter in the winter but keeps it out in the summer.

17. Solar Chimney - draws air through a geothermal heat exchange to provide passive home cooling. As warmed air in the chimney rises, air near the ground is pulled into the pipe, is cooled as is flows underground, and is therefore cooler when it enters the home. This system simply sets up a convection current.

18. Overhangs prevent overheating by the high summer sun. The house works as a cooling tower when windows are opened by venting hot air out of a hatch on the roof deck. This pulls cool air into the lower floors. http://www.backwoodshome.com/articles/heckeroth63.html

19. Keeping the sun out in the summer can include use of solar screens • http://www.sunbloxsolarscreens.com/solar-screens/Gallery/solar-screens-portfolio.html

20. Awnings can also be used to keep sun off a window http://www.builditsolar.com/Projects/Cooling/passive_cooling.htm#Shading

21. A house that incorporates a variety of passive solar elements • The house, which will be built in pumicecrete, features several Trombe walls and an interior courtyard with sunspace. • The Great Room (under the large blue roof) has a sunspace on the south and an array of large low-E windows on the north that face a spectacular view of the 600 foot deep Rio Grande Gorge. • The courtyard provides an wind-sheltered outdoor micro-climate extension of the Great Room. http://www.dennisrhollowayarchitect.com/html/PateByrd1.html

22. Cornell’s entry into the Solar Decathlon 2007

23. Solar Decathlon in Washington DC 2007 http://www.inhabitat.com/2007/10/19/germany-wins-the-2007-solar-decathlon/