Home Improvement : Solar Heater Provides Drinking Water Too
QUESTION: We have a large family and spend over $300 per year to heat hot water. I would like to use a solar system to save money and help save the environment. Are there still solar systems available?
ANSWER: When the energy tax credits were eliminated, many of the high-priced solar contractors went out of business. Although solar equipment that you can use to build your own system is a little harder to find now, it is still available. There are even some new, very efficient designs.
A typical solar system can provide 60% to 75% of your family’s hot water needs throughout the year. The annual savings can total a couple of hundred dollars. Since this is after-tax money, it can be equivalent to $300 to $400 of additional income from your job.
The two most common types of solar systems for heating water utilize flat plate collectors or concentrating collectors. Concentrating collectors use one of several methods to focus the sun’s rays on to the water to produce higher water temperatures or steam.
One new and very efficient solar system uses a small concentrating collector to produce steam and pure distilled drinking water as a byproduct. The collector is rotated by a small motor throughout the day so it continually faces the sun most directly. Being relatively small, it is not very noticeable on your house.
The steam from the collector circulates through a pipe in your existing water heater where it condenses to transfer the heat to the water. On a typical sunny day, it produces about 3,000 BTU/hour.
Tubing runs from the tank to a water storage jug to collect the purified distilled drinking water. It produces more than 700 gallons of distilled water per year. This can save several hundred dollars in bottled water costs or additional energy consumption to operate an electric distiller.
In recent years, photovoltaics (solar cells that produce free electricity) have become much more energy-efficient and cost effective. You can tie these into solar systems to power the small electric motors and controls. It is a natural fit since the electricity output is greatest when the hot water production is greatest.
Before you select a solar system for your home, contact a solar designer to plan a system for your needs. You can always add more collectors to a system as your budget allows.
You can write to me for Utility Bills Update No. 359 describing the new solar water heating system that makes distilled drinking water, a list of solar collector manufacturers and several piping layouts of solar systems. Please include $1 and a self-addressed business-sized envelope. Send your requests to James Dulley, c/o Los Angeles Times, 6906 Royalgreen Drive, Cincinnati, Ohio 45244.
Rust-Inhibiting Paint Works on Baseboards
Q: I have electric baseboard heaters in my bathroom, and the covers on them are rusting due to the moisture. Do I need a special type of paint that won’t adversely effect the heat transfer efficiency of them?
A: Most rust-inhibiting paints are fine, as long the cover doesn’t get hotter than 190 degrees. Although the cover normally shouldn’t get that hot, check with the supplier of the baseboard heaters for the temperature specifications. Painting the cover won’t affect the efficiency.
If the temperature gets above 190 degrees, use heat-resistant paints made for barbecues. Don’t paint the actual heating fins under the cover. They get too hot and the paint can effect the heat transfer properties.
Letters and questions to Dulley, a Cincinnati-based engineering consultant, may be sent to James Dulley, Los Angeles Times, 6906 Royalgreen Drive, Cincinnati, Ohio 45244.
