After a couple of years in the contemplation stage, my wife and I finally decided to build a small backyard water feature. In May 1999, we ordered pallets of Sahara stones, Holland pavers, and sand, with which we hoped to build a small (56″w’ x 64″l x 14″d) pond. Before we began work, a key question was how to power the pond’s fountain. Our 1920s house has no outdoor electrical outlet. Sure, an electrician could install one, but then a trench for the conduit and wires would need to be dug from the house to the pond site. Both tasks were feasible but seemed excessive solutions to the problem of supplying the modest power needs of our little 130-gallon pond.
Using the sun to power our pond had strong appeal. It wouldn’t require installing outdoor electric service on the house and would eliminate the need to cut a trench across the yard. It also meant that enhancing our backyard environment with a pond and fountain could be accomplished without increasing our reliance on electricity made with coal or uranium and all the environmental problems associated with these fuels. After some looking around, I discovered a kit at Smith & Hawkin that contained one 18″ x 12″ photovoltaic panel and a 12-volt DC pump with fountain. My wife and I, however, intended to enjoy our pond and fountain not just on sunny days, but on cloudy ones and during evenings as well. I approached a former work colleague who had recently started his own design business (Duck and Spline). He modified the Smith & Hawkin kit to operate with a marine battery backup. During the day, the photovoltaic panel uses the sun’s energy to charge the battery. We now have the flexibility to use our solar-powered fountain anytime, day or night, and in all weather conditions.
Versatility was not the only consideration. We also wanted the solar equipment to be aesthetically appealing – no solar panel standing out in the open with cables running back and forth across the ground. Duck and Spline neatly solved this issue by constructing a small cedar garden cabinet (30″h x 18″w x 11″d) with the photovoltaic panel comprising the roof. The battery, fountain accessories and control panel were tucked away out of sight inside. This cabinet sits on a metal stand immediately next to the pond, so cable runs are very short. Given the prototypical nature of this project, Duck and Spline designed and built the battery backup system and garden cabinet for the cost of the parts (and a certain amount of beer). My wife and I have had our sun-powered pond for two summers now, and during that time it has performed admirably.
We encourage others to explore incorporating solar power into their urban lives. Besides the features I described above, one more needs mention. On sunny days, we switch the control panel from battery backup to straight solar power. Human eyes readily adapt to changes in sunlight, so we seldom perceive the subtle changes that occur with the passing of even the thinnest clouds. But the solar panel notices, and the variations in the electrical current translate into a continually changeable water dance.
See Also: Arts: Solar Energy