Solar power for cooling purposes

Our church, located on Long Island, is interested in solar cooling as our main concern and heating second. Is it possible to have effective cooling and heating through solar devies? Would we need a conventionl backup system? Jeanette Robertson Rockville Centre, N.Y.

Solar is certainly one way to go, but you would need a conventional backup system in your climate.

The question is: Is it economical? That remains to be seen, according to Ron Stevenson of solar Southwest of Odessa, Texas, a solar manufacturer. Most 3 1/2 -ton systems are running anywhere from $12,000 to $18,000, he says, but this would not be enough for a church.

You would probably buy a total system, not just air conditioning, if you opt to go solar. If you have the heat available to do the air-conditioning load, then you also would have enough to do a heating load, says Mr. Stevenson, plus enough heat left over to heat the water.

Why don't you get in touch with Grumman Energy Systems, a subsidiary of Grumman Corporation.It's located in Bethpage, right there on Long Island. The phone number is: (516) 575-7474.

You can also drop a note to the Northeast Solar Energy Center at 670 Atlantic Avenue, Boston, Mass. 02111. The center will send out free literature, fact sheets, and bibliographies, if you're interested.Also, a call to the National Solar Heating and Cooling Information Center in Rockville, Md., may be worthwhile. The phone number is: (800) 523-2929. If calling from Pennsylvania, the number is: (800) 462-4983.

This should give you enough data so that you can make a satisfactory decision on whether or not to buy a solar system for the church.