This $30 Solar Setup Heats a 30 X 40 Workshop for Five Hours or More Every Sunny Winter Day

Enlarge Image Image Gallery PHOTOS BY DON R. WATERMAN

"For a super-simple and super-inexpensive solar heating system that really works," say Don R. and George Waterman of Springfield, Missouri, "you only have to follow four rules. One, glaze with low-cost plastic film instead of glass or plexiglass ... two, use a structure's existing south-facing wall for the back of your collector ... three, forget about trying to store the heat you collect ... and, four, scrounge!"

If you really want to put solar energy to work for you right now on a minimum-cash-investment basis, you can. I know, because last winter my father, George Waterman, and I supplied a 30 X 40 insulated workshop with almost all of the heat needed to keep the building's interior comfortable throughout near-zero days . . . and we did it with a solar heating setup that cost us a total, out-of-pocket, of only $30.

We accomplished this feat with a fourfold secret of low-cost construction: [1] We glazed our 8' X 30' solar collector with inexpensive plastic film instead of glass or plexiglass, [2] we used our workshop's existing south-facing wall for the back of the collector, [3] we did not build any heat storage into our design, and [4] we scrounged a great deal of the material that went into the solar heating system.

Thanks in large part to the four points listed above, our sun-powered heater was also quite simple in design and went together very rapidly. We put the whole system up with only about a week's worth of work (spread out, due to bad weather, over nearly two weeks). Compare our total time and cash investment to the $1,500, $2,000, or more that 240 square feet of commercially manufactured collectors would have cost (before installation, of course, and before tacking on another ridiculous figure for blowers, ducting, etc.) ... and I think you'll agree that our initial investment was quite reasonable.

Nor will upkeep (which should mainly involve the replacement of our collector's double layer of plastic film) be the continuing expense that you might think. We figure on replacing our film no more frequently than once every two years (it's already been through one winter and looks good for another). But even if we have to change both layers of the plastic every year, it's quite inexpensive (a roll of six-mil polyethylene measuring 8' X 100' cost us only $17). At that price, it'll take 34.5 years worth of annual replacements to add up to the cost ($400) of one original double set of glass collector covers ... and 69 years of annual replacements to equal the cost ($800) of duo plexiglass glazing. We think we've got the trade-off working in our favor.

HOW WE FRAMED AND PAINTED OUR COLLECTOR'S SIDES AND INNARDS

We started our collector by outlining its 8' X 30' area with four 15'-long and two 7'9"?long 2 X 4's. (Since our plastic was just eight feet wide, we used 7'9" uprights on the ends of the unit which, when capped top and bottom by 1-1/2"?thick "2 X 4's", added up exactly to the plastic's eight-foot width.) These 2 X 4's could have been just toenailed (on edge) to the south wall of the shop, but we took the time to mount them in a somewhat more sophisticated (and we think better) way. What we did was first nail 3/4" X 2-1/2" strips of lumber flat against the edges of the 2 X 4's (see detail I sketch on the drawing which accompanies this article). Since the so-called 2 X 4's sold today actually measure only 1-1/2" by 3-1/2", this means that the strips formed a lip measuring 3/4" deep and a full one inch wide completely around the 8' X 30' circumference of the collector frame. And that then made it awfully-easy to attach the frame(right through the lip) to the shop's wall with wood screws.