SOLAR THERMAL ROOF

Energy independence is possible the sun is taken into consideration when designing a house. Some people say that solar houses don't  have to be any different than any other house. I say it all depends on what you mean by a solar home. If you're thinking of energy independence in a cold climate special considerations a large surface area will be needed for collecting the sun's energy and a large storage area will be needed to store that heat... and we haven't begun to talk about insulation. We have grown accustomed to living in rectangular dwellings that waste heat as well as valuable attic space . Developers and builders are not concerned with the orientation of roofs for possible solar heat gain. They are more concerned with selling traditional style houses that facilitate the process of acquiring a building permit and are easy to sell. The solar housing market could definitely use better government incentives to promote energy efficient solar home designs. Since renewable energy benefits the well being of everyone I believe government should give property tax reductions based on energy renewable energy used. It is now possible to build energy independent solar homes at a cost per square foot comparable to traditional style housing, but don't  expect this house to look the same as the house we are now living in.

This three story solar home gets all it's energy from the sun. Photovoltaic panels, not shown, would be mounted on the shed roof to supply electricity, and a built in solar thermal roof on the front  supplies all the needed heat. This house uses the entire surface area of the roof to harvest the sun's energy. Why shouldn't we use our roofs to harvest free energy? What else are we using them for other than to shed water?
An additional, unexpected benefit of this house style is a third floor that would normally be wasted attic space, and a large solar greenhouse on the the front. Side windows are not shown. I'm leaving this up to your imagination.

A cross sectional view should give you an idea of the internal space available. Notice the heat storage vault under the solar greenhouse. There is no need to waste valuable basement space with this large storage vault that may be accessed from the floor of the greenhouse. 
A futuristic possibility of a design like this has to do with the hybrid potential of a  solar thermal engine working in conjunction with the solar heating system.

 

 

 Low temperature Sterling Engines do now exist that are capable of converting flat plate collector heat into electricity, but I have a more efficient design in mind. 

A more futuristic solar thermal design might be based on something called a cube octahedron. This one floor building was designed as a proposal for the Solar Energy Center at Farmingdale University, NY. The cube octahedrons  has a naturally occurring  steep pitched, ideal for harvesting winter sunlight. The 250 sq ft roof should keep this well insulated structure above 600 F all year.  A few PV panels and perhaps a differential thermal engine could supply all or most of the power requirements. 

This simple one story hexagonal house has a diameter of 32 feet and an interior ceiling 12 feet  high. It has a full basement insulated on the outside and stuccoed with Ferro Cement. Hexagonal units like this may be combined to make a variety of shapes suitable for luxurious living arrangements. Hexagonal units may be combined in a number of ways to increase living space arrangements like this:

The house below has is seventy feet long and varies in width between 16 feet and 32 feet. The available living space is about 3,500 sq ft. The 750 sq ft solar thermal roof should harvest about 3,000 gallons worth of heat per year.

 

Now it's time for you to get out a pencil and design an energy independent home of your own that uses a solar thermal roof. Show the dimensions of the house, the size of the solar thermal roof, the living space, insulation factors and annual expected heat gain. Upload your sketch and calculations to the Solar Thermal Roof  on the Bulletin Board .