JAMES DULLEY Cutting your utility bills How to reduce fuel dependence
Q. I have considered getting a solar water-heater kit to cut my utility bills and protect the environment for my children's future. How do I know if one will be effective on my house, and which type is best?
A. Heating your domestic hot water with solar energy can be effective on practically any home. The only requirement is finding a spot in your yard or on the roof that has direct exposure to the sun most of the day. This is not a problem on 95 percent of homes.
The economic payback on installing a solar water-heating kit (some have do-it-yourself installation) depends on your utility rates and the amount of hot water your family uses. As with any product, there are economies of scale, so the more hot water you use, the more economical solar energy becomes.
With low interest rates and poor stock-market performance, installing a solar water-heating kit can be a good investment. Using solar reduces air pollution, global warming and our dependence on foreign energy supplies. Very little maintenance is required, and some kits offer a 12-year warranty.
The new designs of solar collectors are smaller and more efficient. Many are designed to lie flat against your roof so they are barely noticeable from the ground. They are shallow, only a few inches deep, so they resemble a skylight from the ground. They are lightweight, so installation is easy.
Pump or no pump?
There are many types of solar water-heating methods to choose from. The simplest designs and easiest-to-install kits use a thermosiphoning water flow. These are typically mounted on top of your house or garage roof.
Thermosiphoning (sometimes called passive) works on the principle that hot water is less dense than cold water so it naturally rises.
Thermosiphoning keeps water flowing through the solar collector without electric pumps. For this reason, the collector must be mounted higher than the water heater.
Solar water-heater kits with electric pumps offer more flexibility in choosing an effective, sunny location for the collectors. For a totally independent system, choose a 12-volt pump and a small solar-cell panel to produce electricity. Mount the solar-cell panel next to the collector.
Many solar water heaters use a simple flat-plate collector design. It is basically an insulated box with a glass top. The water flows through copper pipes that are attached to black solar collector plates inside of the box.
Another unique and effective design uses evacuated double-walled glass tubes instead of heavy insulation. This insulates efficiently and keeps the water hot in the same way a Thermos bottle keeps your coffee hot.
Q. I live in an older house, and there is no return air duct from the second floor. This makes it difficult to heat and cool the upstairs well. What is the easiest method to add a return duct?
A. Having just a single return air duct on the second floor can make a significant difference in getting heated and cooled air up there.
One method is to run a vertical return duct through a closet.
Because many older houses have a laundry chute from the second floor to the basement or laundry room, you can use that for the return duct. Just mount a grill where the second-floor door was and run a duct from the lower opening to the main return duct.
XWrite for Update Bulletin No. 443, which gives a buyer's guide of easy-to-install solar water-heater kits listing collector type and size, features, plumbing layouts, sizing chart and prices. Please send $3 and a business-size SASE to James Dulley, The Vindicator, 6906 Royalgreen Drive, Cincinnati, Ohio 45244. For an instant download, visit www.dulley.com.