Mother's Do-It-Yourself Collector Comparison

Enlarge Image Image Gallery Top Left: Mother's in-line collector. Top right: The BTU Bucket without glazing. Center left: A three-pass version of a SolaRoll unit. Center right: Suntree's kit collector has 17 tubes. Bottom left: Suntree's collector box is now made of aluminum. Bottom middle: The BTU Bucket tubes must be joined to its headers with solder. Bottom right: SolaRoll's 36 fluid-carrying passages are seaded to the headers by pressing the rubber tubes - with Teflon jam sleeves inside - into preformed openings. Staff Photo

Solar technology is, at long last, beginning to have the opportunity to help alleviate our country's present energy predicament, and most experts acknowledge that, of all the sun-power applications currently in use, water heating systems offer the quickest return on the dollars invested. In fact, depending upon the equipment selected and the labor involved in installing such devices, domestic solar water heaters can pay back every penny laid out for their purchase (in the form of the savings that result from not using conventional energy) in as little as two years.

Consequently, MOTHER has been keeping an eye on the solar collector market, and—in particular—we've been pleased to see a number of sun-power kits appear. After all, considering that the cost of labor usually constitutes at least half the purchase price of most manufactured goods, many folks would be tickled to supply some of that valuable commodity themselves . . . and pocket the difference.

Of course, when faced with the possibility of choosing among the collector kits available, the potential purchaser has a number of questions to consider, such as: Just how difficult are they to put together? How well do they actually work? Are the finished do-it-yourself water heaters as good as factory—assembled items? Are they more efficient (and/or easier to build) than are purely homemade jobs (such as MOTHER's In-Line Collector, featured in issue 67) . . . and, if so, are they enough better to justify the additional cost? For that matter, is any one company's package significantly superior to another's?

Since we thought you'd appreciate having answers to such questions, we acquired a representative sampling of the assemble-them-oneself solar boxes, with the idea of seeing how they actually do stack up. In this issue we're going to tell you about the cost of—and the effort needed to put together-several different kits (and review the construction of our homemade in-line collector), then go on to preview our testing procedure . . . the results of which will be reported in detail in MOTHER NO. 71.

THE BTU BUCKET

Solar Usage Now's BTU Bucket is—by virtue of its fiberglass box and aluminum absorber plate—by far the lightest of the collectors we put together. And with 14.2 square feet of glazing, the $99 package is also the least expensive kit . . . at about 1$8.00 per square foot (including the added cost for insulation).