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Stylized Text: Solar Hot Water Q&A.

How can I save even more energy and money with my solar system?

The answer to this question was provided some time ago by Doug Root, a former FSEC Education Consultant and authority in the solar energy field.

If you're the proud owner of a solar domestic water heating system, you know you're saving money. And there are a few minor steps you can take to help save even more. Just adjust your water-use patterns and take a few minutes and pennies to make a few changes. Here's how:

  • Replace the washers in any dripping faucets. They're water and energy waster.
  • Shower and wash clothes and dishes late in the day, after the sun has heated your water.
  • Whenever possible, use the cooler cycles on your clothes washing machine.
  • Turn down the thermostat on your storage tank's electric booster element down to an acceptable level if you don't need very hot water for washing clothes or dishes. If you need hotter water, set the thermostat at 120° F.
  • During warm, sunny weather, turn off the booster element completely.
  • Mixing and anti-scald valves are adjustable, so if your system has one, set it down a little each day until you find the lowest acceptable level for your home. Then set it back up three to five degrees. This will minimize heat loss through pipes where hot water is left after you've finished showering, washing clothes or whatever.
  • Whenever possible, use cold water, not hot. If you wash your hands at a sink some distance from the hot water storage tank, you'll probably have finished by the time the hot water reaches your faucet. This leaves hot water in the pipe where it cools down. If that's only one gallon of 140 ° F water, the loss amounts to about 575 Btu of heat energy. It will take a square foot of your solar collector most of a sunny day to replace that lost energy. You could have used it for something else.
  • Superinsulate your hot water rank and pipes. For the tank, use a wrap-around fiberglass blanket. Kits are available in hardware and plumbing supply outlets at very reasonable prices. Insulate both the cold-water feed line to your storage tank and the hot-water service line coming out of the tank. Use sections of formed insulation (it can be split and reglued with rubber cement for easy installation) or spiral wrap the pipes with plastic-backed strips of fiberglass insulation. In addition, make sure the circulation piping to and from your solar collector is insulated - even in the attic.
  • In Florida, a solar water heater can save an average 15 to 30 percent of your total annual electric bill, depending on the overall hot water usage. To make sure you're on the high end of that percentage range, take the steps advocated here. They cost very little money (if any) and won't cramp your lifestyle. They simply make good energy sense.