Like many backyard inventors, Dan Lightfoot of Sigourney, Iowa has been interested in alternate energy concepts for some time — about 22 years, as a matter of fact. Unlike most of his peers, however, Dan has managed to make a major breakthrough in his field — one which even has the "experts" shaking their heads in disbelief.

That breakthrough is the Hot-Line solar collector you see pictured in the Image Gallery. At first glance, the Hot-Line module looks just about like a conventional flat-plate collector. What makes Lightfoot's panel highly unconventional is that it [1] contains a specially curved reflector which acts to concentrate incoming sunlight on a wedge-shaped absorption tube, [2] operates with an efficiency far surpassing that of any "normal" flat-plate solar panel, and [3] actually "tracks" the sun through a 50 degree vertical arc — and through 150 degrees in the east/west plane — without moving!

Impossible? That's what a University of Iowa physics professor said when Dan Lightfoot first explained the design to him. Rest assured, though, the device does work, and rather well, at that.

So well, in fact, that Lightfoot (after selling exclusive manufacturing rights on his invention to the Iowa City-based NRG Corporation) has recently been able to quit his job with a mining firm and devote full time to energy research. Lightfoot now heads up an outfit called Aerco, which is short for Alternate Energy Resources Company.

Dan Lightfoot came upon the idea for the Hot-Line collector quite by accident a decade ago. It seems Dan had been observing a sheet of aluminum that was resting up against his garage wall and noticed how the sun's reflection from that curved sheet formed a bright spot on an adjoining wall. Moreover, he noticed that the bright spot stayed in roughly the same place throughout the day, despite the sun's constant movement.

This got Dan to thinking, and to experimenting. With the aid of a small sheet of aluminum, a few scraps of wood and a handful of bolts and clamps, Lightfoot found (by trial and error) that he could curve the metal in such a way that it would focus light in a line — a line that, furthermore, moved only a small distance in or out from the metal as the jury-rigged reflector was tilted through various angles to the sun.

At this point, Dan knew that if he could just bend a long sheet of reflective material to the same curvature, lay a channel along the focal plane of the reflector thus created, and run air or water through that channel, he'd have what no one had developed before: a fixed-position, concentrating solar collector. (Focusing collectors are nothing new, of course, but they all have one drawback: in order to work, the reflector must face squarely into the sun at all times. This usually calls, in turn, for a costly and complex motorized gimbal mounting, to allow tracking of the sun. In contrast, Lightfoot's collector can focus light all day long while remaining stationary — a "major breakthrough" indeed!)