Solar Water Heating
The least expensive way to harness the power of El Sol is to heat your water with it. Antifreeze circulates through black tubes up on the roof, where the liquid absorbs heat, and then through your hot-water supply, where it releases that warmth. Since that's not enough to get the water fully hot, the system pre-warms the water for your conventional heater, lowering your water heating costs, which are about 14% of your energy bill, by 50% to 70%.
Cost: $4,000 to $6,000
Payback time: five to nine years |
Ground-Source Heat Pump
These units, which can knock 40% to 70% off your total energy bills, make use of the energy stored deep in the earth. In the summer they expel indoor heat—except instead of releasing it into the air, they discharge it hundreds of feet underground. In the winter the pump works in reverse, concentrating underground warmth and using it to heat your house (you'll need to keep your old heating system as a booster for very cold days).
Cost: $15,000 to $30,000
Payback time: three to 10 years |
Solar Electricity
The problem with solar panels has always been what to do when the sun isn't shining. With today's systems your house stays on the electrical grid, which supplies whatever power you need at night and on cloudy days. But when the sun is out, the solar cells produce more electricity than you can use, and the excess goes out to the grid through a two-way meter. The juice you supply is usually credited against what you draw from the utility and should result in a 70% to 100% savings on your electric bills.
Cost: $20,000 to $30,000
Payback time: five to 10 years |
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Just a couple of years ago the only people putting solar panels on their houses wore Birkenstocks and preferred tofu to T-bones. But now that energy bills are skyrocketing and it has become downright fashionable to reduce your carbon footprint, the idea of adding solar electricity to your home doesn't sound all that far-fetched to the rest of us. Green technology has also become more cost-effective, thanks to the economic stimulus package, which offers a 30% tax credit for extreme green projects completed before 2017.