If you’re reading this article, then you are most likely a first time home buyer who’s considering buying an energy efficient house to call your own. You have heard about passive solar no doubt and are wondering exactly what it is and if it is right for you. Lucky for you, we already did much of the research and we’re presenting it now in such a way that people like you will be more informed in making important decisions about building your new home. Let me explain to you what passive solar is…
Passive solar design is a system designed or incorporated into a house that collects the sun’s energy and subsequently uses it for heating and cooling purposes. The house itself takes advantage of natural energy characteristics in materials and air created by exposure to the sun and strategic shade. It is more commonly utilized for heating during the low temperatures of winter but your house can also stay cool in the summer as passive solar houses utilize shading to keep the building cool too.
Passive systems are very popular these days because of its simplicity and its green home characteristics. The best way to utilize passive solar is by having it designed into the home before it is built. It is also well-known because it requires few moving parts and minimal maintenance. Passive solar can save you bundles on your heating and cooling bills if implemented correctly. The biggest disadvantage of passive solar is that it works best being designed into a home before it is built rather than applied after the home is built. So how does it work?
A passive solar home collects heat as the sun shines through windows and retains this thermal energy in materials that store heat. During winter, the sun will course through a direction that would shine more light on the southern part of your home. Therefore passive solar homes typically have windows placed on the southern facing side of the building in order to maximize its absorption of the sun’s heat energy. During summer, no need to worry about too much heat because the sun will most likely be in a position where its light will not hit the southern side of the house. See image below.
According to the Sustainable Sources website, there are established guidelines that, when followed properly, can contribute to maximizing the heating, cooling, and day-lighting of nearly any building or home. Listed below are some of these passive solar systems rules of thumb:
- The building should be elongated on an east-west axis.
- The building’s south face should receive sunlight between the hours of 9:00 A.M. and 3:00 P.M. (sun time) during the heating /winter season.
- Interior spaces requiring the most light and heating and cooling should be along the south face of the building. Less used spaces should be located on the north.
- An open floor plan optimizes passive system operation.
- Use shading to prevent summer sun entering the interior.
One last thing to remember before building your dream home: the south side of your house must have an unobstructed view of the sun during winter for passive solar to work. If the sunlight is currently unobstructed, then think of possible future changes or developments in your lot or neighborhood. Consider the fact that trees grow bigger, and in the future a new neighbor might decide to build a multi-story house. Luckily, in some areas, zoning or other land use regulations protect landowners’ solar access. Ask your home builder about land use regulations and policies in your area.