When designing an off grid sustainable home, it is best to design the majority of the windows facing south to utilize the most amount of solar gain. During the winter it is crucial to let in as much natural light as possible. This cuts down on the use of electricity and the need for electric lights during the daylight hours.
The other important factor is heat. With south facing windows, the home heats up with the incoming rays from the sun. The sun travels lower in the sky because of the tilt of the Earth’s axis during the winter. This allows more sun to enter the home through the windows. During the summer, the sun’s light does not directly enter the home, keeping the home relatively cool. Now that Autumn is upon us, the mornings feel relatively chilly. The outside temperature has dropped to thirty-four degrees, while the home’s residual heat from the day before is around seventy degrees. Sometimes putting on a sweater is the best answer in the mornings because by 11:00 am the home is warm and comfortable from the incoming sun. On cloudy days, when the temp drops below seventy and doesn’t seem to recover, we build a fire in the wood cook stove and let it burn itself out. The one fire heats up the home nicely and allows us to cook one meal without having to use our propane stove.
When looking at housing designs, it is important to check and see how many north facing windows a home has. North facing windows are on the permanently, shady side of the house and provide no heat value to your home. In fact, a north facing window actually causes the home to lose heat during the winter faster than if an insulated wall was in its place. In our home we have one north facing window with the room centrally located in the home, heating it has not been an issue and the residual light is nice.
Unfortunately, our society and culture does not look into the orientation of the home to the sun. We do not consider “passive solar home designs”utilizing the sun to heat our homes or to provide light for them. Homes today are designed to utilize artificial light and heat. We are conditioned to like the artificial over what is natural. Homes are being designed to be larger, but they do not utilize the living space well in considering heating costs and lighting.
Personally, people can design and purchase whatever home makes them happy, and they should. However, when talking to people about their homes, I hear many people over the years complain their home is difficult to heat, or it feels dark to them all the time; this is because the home was not constructed using a passive solar designed. Also with the advent of subdivisions it is very difficult to get every house to utilize passive solar design, especially, if the builder has no interest to do so. Even if a home is not using passive solar design many can be remodeled to utilize the natural heat and light from the sun.
The good news is many people are beginning to recognize the importance of passive solar home designs, for example, this article at the National Renewable Energy Laboratory (NREL). Even the United States Department of Energy realizes the potential of passive solar home designs. Perhaps in the future, people will see the importance of passive solar home designs and begin demanding their next house has it. Imagine on HGtv, instead of buyers wanting stainless steel appliances and granite counter tops, people actually oohed and awed over an energy efficient home using passive solar design. Or, maybe that day is already here?