Solar Energy is an Excellent Alternative

By Carroll Colette J. Yorgey

Solar energy is an excellent alternative energy for heating and cooling homes, buildings, and urban areas and should always be included in the architecture and urban planning of new urban areas. There are important reasons to include solar heating and cooling into urban planning and architecture. The most important reason is that if it is not included and solar energy is decided after the buildings are already built, the building will never be conducive to good solar energy because there are building and design specifications that need to be met to provide for cost-effective and heating/cooling-effective energy.

There are two kinds of solar energy, active and passive.

Active solar energy

Active solar energy is the kind of solar energy that most people think of when deciding to go solar with their existing homes. Active solar energy is mechanical and relies on mechanical equipment and a mechanical distribution system. Active solar can be very expensive, since the building was never built or designed to include solar energy. Solar collectors are expensive.

Passive solar energy

Your building becomes the solar collector if it is designed using all solar energy architectural principles. Passive solar energy stands on its own and will not be converted to electricity. Passive solar energy uses non-mechanical ways to collect and transport heat such as radiation, conduction and natural convection.

When deciding to use solar energy to heat or cool your home, passive solar energy will provide the best source of natural heat and natural cooling at the least amount of cost.

In order for a home or any building to effectively use and produce passive solar energy, the building must be planned according to certain solar energy architectural principles.

Location of building

A passive solar home or building should be built in the north end of a sunny area in order to utilize the south end for solar energy.

Location of indoor spaces

Each indoor space must be planned according to how much solar energy is needed to heat and cool that space.

Climate of the area

The location and shape of the building will depend on the climate of the area – are the winters cold or are nights cold? If a cold climate the area that receives the most sun during maximum solar radiation will have to be determined.

Shape of the building

The shape of the building must be designed for optimum interior sunlight. Usually a building that is elongated on the east/west axis will provide the most sunlight.

Position of the sun

Passive solar energy depends on direct sunlight. The more direct sunlight the less conventional energy is needed for heating and cooling.

Trained solar architects will use different types of sun charts and solar radiation calculators to determine exact positions of the sun on given days and given seasons to help them determine the best shape, position, and location of new buildings and urban construction.

Therefore in order to build and plan urban buildings and urban areas according to solar principles, there must be an original architectural design that is mapped out according to the location and climate of the area, and positions of the sun. These details must all be worked out in advance of designing the building or urban area. Once there is a plan according to solar architectural principles the building can be designed according to these principles.

A trained solar architect will be needed for large urban areas or large building complexes such as schools and office buildings. A caring homeowner may be able to build according to passive solar principles if he studies and reads up on passive solar design.

If you already have existing architecture and want to go solar it is important to utilize all spaces as much as possible for passive solar and then determine how much active solar you will need to make your home or building energy efficient. You may need to use a combination of alternative heating and cooling sources rather than relying entirely on solar heating and cooling. Adding on such as adding a greenhouse can be an effective way to use passive solar in an existing building or urban area, but it will never be as effective as planning the complete solar building right from the beginning.

Reference: Mazria, Edward. 1979. The Passive Solar Energy Book. Emmaus: Rodale Press.

Copyright © 2018 Carroll Colette J. Yorgey. Edited and used with her permission. Image from “Bête spatio-temporelle” on Wikimedia Commons is CC 4.0 licensed.