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In the 1970s many people assumed that by the turn of the century most new homes built in the United States would be designed to make effective use of solar energy. Federal energy policies promoted solar energy and conservation and provided tax credits for households that installed solar energy for heating or hot water. Many existing homes were built or retrofitted with various kinds of solar energy devices. This momentum stalled somewhat during the 1980s and 1990s. Hopefully, we will make more progress in the twenty-first century. In any event, the move to solar energy has already begun. Today thousands of homes are fitted with solar energy systems.
Even if the idea of a solar energy system doesn’t immediately appeal to you, read on. There are some money-saving ideas here that everyone can use.
To start with, you’re already using solar energy: The sun light that comes in through every window adds to the heat in your home. Unfortunately, at night your heated air leaves through these very same windows. That is why good draperies or insulating window shades are so effective.
The most light, and therefore heat, enters through your south-facing windows. These windows are the most effective solar collectors you can have. I’m not talking about some new invention by which you can make your house look like a space station. I’m talking about plain, old-fashioned windows.
Solar heat is obviously present on every clear day. Not so obviously, it is still with us on cloudy days. In fact, even on a dim day, the hours of daylight have something to offer for reducing your fuel bills.
If you get intrigued with the solar possibilities, there are books and plans available that will take you beyond the scope of this section. Here I suggest things you can do right away, at minimal cost and effort, to take greater advantage of that great free source of energy, the sun.
Use Solar Heat — Now
Don’t think of solar heat as something for the future, in a new home. Make use of it now. Here are some ways to do it.
• Begin on the outside of your house. Black and other dark colors absorb sun warmth; white and light colors reflect that warmth. Assuming you live where it gets cold in the winter, darker colors for your house exterior, particularly your roof, will pass more of the available heat from the sun to your house.
• You can get sunburned under water; you can get sunburned on a cloudy day; you can get sunburned through a T-shirt; and you can get sunburned on a ski slope when the temperature is below zero. Naturally, the windows of your house, and especially those facing south, can admit a lot of heat from the sun.
• Storm windows will impede the passage of sunlight very little, but they do keep in more of the heat once it has entered your house.
Most conventional greenhouses have glass on four sides and a glass roof. The plants get a lot of light, but the heating bill can be enormous. At night, the heat leaves through the glass walls and roof. A solar greenhouse usually has a large, sloped south-facing area of glass to receive the light the plants need to grow. However, the other sides are well insulated to reduce the heat loss to the outdoors.
• In a solar greenhouse, sun heat is stored in the soil and in water containers. At night, this heat radiates into the green house and keeps it from getting too cold. Take advantage of this concept throughout your house by having solid objects with an ability to store heat standing in the sunlight to store warmth that will be radiated after the sun goes down.
• One good heat collector is a windowsill row of flowerpots or an indoor window box. The dirt will store warmth during the day, helping the plants to grow and warming the room at night.
• In your house, can the low-lying winter sun slant across the room to warm a brick-fronted fireplace, a slate entryway, or a similar solid surface? Be sure the drapes are pulled back to take advantage of these solar collectors. Don’t forget to shut the drapes at night to keep in warmth.
• Light-colored shades or slatted blinds drawn across a sunny window will reflect the sun’s warmth right back outdoors again. During the daylight hours, keep the sunny windows in the clear to let that warmth in.
• The first step into solar power for many people is a solar hot water system. Such systems are available for new homes or for retrofitting on older homes. They will furnish 50 to 100 percent of your hot water requirements. Look at your cur rent cost of heating hot water and talk to a contractor about the costs and possible savings of a solar system. Ask your contractor for references so you can get a better idea of how much people in your area save with their solar hot-water heaters.
• If you have unused space up under your roof — and this will certainly be true if yours is a house with a truss-roof design — consult with a plumber on the cost of putting a secondhand, uninsulated hot water tank up there. Make sure your attic floor can support the added weight. At least during the warmer months, the upstairs tank, linked to the water lines before the water gets to your regular heater, will preheat the water, making for less fuel usage for household hot water. If your roof is insulated, that space up top will be warmer than the outdoors even in winter, so the tank up there can pre-warm your water year-round.
• Sunshine is not only a source of warmth but also a source of light at the same time. Turning on the light switches in the daytime may be a habit you can break just by rearranging the furniture or opening the blinds more often.
• Next time you’re ready to repaint or repaper a room, think about how the room is used before you choose the colors. Light colors in a room will bounce the daylight around, making it a pleasant and cheerful place without extra illumination. This is a less important factor in bedrooms, which are used primarily at night.
• In fact, in rooms used solely for sleeping the main function windows have is to provide a little ventilation. Wintertime solar heat won’t be available when the room is in use, so let the windows be small, or heavily draped.
• Window light can be scarce in the kitchen because you often want a lot of storage, rather than windows, on the outside walls. It’s even more important, then, to choose light colors for the kitchen walls.
• If you’re designing from scratch, or doing a major remodeling, think about a combined kitchen-dining area with storage on the north wall and windows on the south and east walls. That way you can have both storage and sunshine.
• Whenever possible, place daytime reading and working areas where window light will be sufficient on all but the most overcast days. Specifically, consider the location of the sewing machine, the chair with the magazine rack, the play table for the children, the workbench, and items like an artist’s easel or a computer. Light also means heat, so you’ll be warmer as you work.
• Are you planning to turn a dark attic into a bright living space? A skylight could change a gloomy garret into a pleasant place. Make sure you install a high-quality window or the heat loss in winter will more than cancel out the savings you gain from the daylight. Look for a double paned window with at least ½-inch air space between each pane. Low-e glass or argon-filled units will reduce heat loss. Some skylights include shades to reduce overheating during the warm months. You can also use the shades, particularly if they are made of a fabric that insulates well, to keep the heat in at night. Finally, select the model with the lowest rate of infiltration.
The Solar Room
Some direct uses of solar energy are available to you. You might consider the sunspace or solar room, a less expensive feature than a full-scale greenhouse.
• The solar room will do best on a south wall. The next best choice is an east or west wall, depending on when you use the room and how much the windows are obstructed. It’s best to have minimum shading in winter and some summer shade to keep the space cool.
• Your solar room will gather heat even during overcast winter days. Look for ways to conduct that heat to the rest of the house, such as a window or small fan.
• The nighttime temperatures in your solar room will be significantly lower than in daytime, so avoid growing exotic tropicals that would require supplementary heat.
• Any well-insulated south facing room with a large amount of south-facing glass can provide a wonderful solar-heated space. A back wall and floor in a dark color and of solid masonry — like concrete or stone — will retain sun heat into the nighttime hours. To avoid overheating, minimize skylights and include adequate ventilation.
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