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Mother's Super-simple Solar Tracker

Burkholder improves on Steve Baer's design using freon.

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MOTHER's Dennis Burkholder develops a $34.49 solar tracker that works better than some $200 units we've seen!

Anybody who's ever played around with solar energy (and that includes a lot of us these days) usually devotes a great deal of his or her early experiments to the fabrication and testing of flat-plate, parabolic, and other collectors of the sun's rays. And, sooner or later, he or she begins to think about how much more efficient (about 40% more) most of those collectors would be...if they only had some sort of mechanism built into them to keep them pointed directly at the sun all day long as it travels across the sky.

Now, there are a lot of solar tracking devices floating around at the present time...based on everything from wind-'em-up clockwork mechahisms to silicon cells to bimetallic gizmos of one sort or another. The only trouble is that all these gadgets are either expensive, or complex, or must be recalibrated frequently, or require an outside source of power with constant frequency and voltage and a separate feedback path to correct their errors ... or some combination of the above.

What the world (or, at least, the solar energy experimenters' section of it) has long needed is a supersimple, superinexpensive, superself-contained solar tracker that'll work dang near forever on—and only on—the energy it receives directly from the sun.

STEVE BAER TACKLES THE PROBLEM

The folks here in MOTHER's research lab were impressed a year or so ago when Steve Baer (who often does such things) published a report entitled "Gravity Drivers". Especially since one of the gravity drivers described in that paper looked something like the setup shown in Fig. 1.

Now this is really a clever outfit. What you've got, you see, is a flatplate solar collector supported on a pivot so that it can follow the sun as It travels from east to west during the day. And the mechanism which makes the collector track the sun that way... is hardly any "mechanism" at all: just two long tanks filled with Freon 12, partly shaded from the sun, and connected together by a hose.

Why Freon 12? Because unlike water, which—at sea level—boils (which is to say that its vapor pressure exceeds atmospheric pressure) at 212°F... Freon 12 boils at a somewhat lower temperature than -30°F. Or, to say it the other way around, Freon 12 poured out into a bowl and exposed to the air will stay in that bowl (remain a liquid) only at temperatures colder than -30°F. At any higher temperature, it will simply boil away?evaporate?into the atmosphere.

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