New Maine product; Solar heating system is simple, much less expensive

Two years ago Allan Fernald had some solar-heating panels installed on the Camden, Maine, mansion that houses Down East magazine. The panels worked so well that, like the man in the electric-shaver advertisement, Mr. Fernald bought the company, Hanson Energy Products, located in this coastal Maine town.

Others share the Fernald enthusiasm for the simple and relatively inexpensive Hansolar panel, as it is called.

Last year Popular Science magazine decided to test the product before giving it any mention in its editorial columns. The results were so satisfying that the panels made the cover story in the September issue.

Solar-heating panels work somewhat like the car that is parked in the sun with its windows tightly shut. The sun, streaming in through the glass, heats up the seats, dashboard, steering wheel, and anything else that is inside the car. These things, in turn, heat up the surrounding air, often to uncomfortably warm temperatures.

For their part, solar panels - placed on a south-facing roof or wall or even just free-standing - work in this manner: the sun, shining through the glass outer cover, is abosrbed by a black collector plate which becomes very hot. Cool air from inside the building is then drawn across the hot plate, absorbing much of the heat before returning to the house or office, often 40 degrees warmer than when it left.

How does the Hansolar panel differ from other solar panels on the market?

Well, for one thing, it was designed with the handyman in mind. A majority of people who work with tools in their basement could install the panel themselves. This same simplicity also means that a professional installation should come in at under $200.

The twin-panel set currently retails at around $500, one-tenth the cost of many systems and half the price of the nearest competitor. Federal and state tax allowances effectively cut the cost by more than 50 percent in most states (in Maine the figure comes in at $185).

Several years ago Dave Hanson, a former aircraft and missile designer for Boeing in Seattle, moved east and bought the Clarke soda-bottling factory here. That's when Hanson discovered how costly it can be to heat a 7,000-square-foot building in this corner of the Northeast.

Hanson's cost-cutting solution was to design a simple solar-hot-air system that did away with bulky and costly heat storage. It worked so well that he cut his oil use that first year by 65 percent.

Such a dramatic drop got Mr. Hanson to thinking. If solar heating could be made both simple and inexpensive, widespread public acceptance might come about. He could well be right.

(The Hansolar unit includes two collector panels, each 36x38x51/2 inches, mounting brackets, duct pipes, and blower.)

After many prototypes, production began in 1979. The 300 first-year sales figure jumped to 600 in 1980, reaching 1,600 in 1981, the year Fernald and his partner, Stephen Spahn, bought the company, retaining Hanson as designer and director of research.

Last year 7,000 panels were sold from Maine to New Mexico, while 1983 sales are expected to top 15,000 - with 50,000 projected for 1984.

Hanson is quick to point out that ''other top-quality systems'' match his in terms of cost per cubic foot of heated air. But these are whole-house systems involving considerable thermal mass, such as a large volume of crushed rock in the basement.

The Hansolar panels, by contrast, provide fuel-free heat only while the sun shines. At night, or on cloudy days, the building would rely on conventional heating. The panels reduce, but do not eliminate, heating bills. Or, as Hanson says,''When the sun shines, the furnace can take a rest.''

Two panels, pumping in 80 cubic feet of warmed air a minute, effectively heat an average-size room. The blower that comes with the initial two panels is powerful enough to pump air through any additional panels that might be added at a later date.

For further information write: Hanson Energy Products, Newcastle, Maine 04553 .