Are you interested in adding solar energy to your home? You can spend thousands of dollars on solar panels, thin film, inverters, batteries, water heaters, etc.
But solar doesn’t have to be expensive.
If you’re building a new home, or remodeling an existing one, you needn’t spend a great deal of extra money to take advantage of the power of the sun. Incorporating the principles of passive solar design will make your home easier to heat and cool, and keep you more in touch with the natural cycles of the day and year.
Passive solar heating is older than humanity. Just watch your dog or cat seek out the sunniest spot in the room – or a shady place under the fence when the day gets hot. He knows instinctively how to keep himself comfortable using the sun.
A passive solar home uses smart design rather than mechanics to stay warmer in the winter and cooler in the summer. If you’d like to incorporate passive solar into your home, keep in mind the five elements of passive solar design:
1. Orientation – In the Northern Hemisphere, the sun tracks from east to west across the southern part of the sky in the winter. Position the house so the longest side faces the sun to take full advantage of passive solar heat.
2. Windows – Large windows on the southern side of your home allow sunlight in to help warm the building. When you’re aiming for passive solar heat, keep north windows to a minimum. They don’t let in much direct sunlight anyway, and that way you’ll also be avoiding drafts from the coldest winds. In very hot climates you might want to keep sun-side windows small and open up the shady side to keep the building cooler. Many passive solar homes feature angled glass on the sunny side to capture a greater portion of the sun’s heat.
3. Shading – Even in cool climates you’ll have some hot days. And you’d be surprised how warm a passive solar living room can get on a bright sub-zero day. Window shades, curtains and awnings keep the sunlight from overheating your passive solar home on sunny days. With the sun higher in the sky in the summer, awnings and roof over-hangs alone can often effectively cut the solar heat in the summer.
4. Insulation – In passive solar design, you want to let the sun’s heat in through windows, and then keep it from escaping. It’s essential to have plenty of insulation wherever you don’t have windows – especially in the roof. It’s also a good idea to have insulated shades or curtains to help prevent heat loss at night.
5. Thermal mass – the biggest problem with passive solar heat is that you only get it when the sun is shining. It’s important to include heat-retaining material in your home’s passive solar design. Materials like stone or concrete soak up the heat when it’s plentiful and help keep the home from overheating when it’s warm. They also act as a heat “battery,” slowly releasing heat as the building cools. It’s especially good to locate these materials where the sun will hit them, like in the floor.
Cultures around the world have used passive solar design for thousands of years to keep their buildings warmer in winter and cooler in summer. You can, too! It’s a smart way to build energy-efficiency right into the structure of your home.