Solar Water Heater

• From April through mid September the sun heated our water so hot that we warned guests of the danger of scalding.
• Clouds cut off the amount of energy (http://www.science.org.au/nova/005/005box03.htm ) available to heat the water, but clouds in the summer are few and fleeting.
• In the autumn, on rainy days we turn on the electric water heater, the way we did last February and March. About an hour gives us water hot enough for showers, two hours on cold days.
• It only rains from October through April (with the occasional storm surprising people into May), for a week or two in late fall or early winter, now and then in January and February, and, if all goes well, for several days in March or April. In the depths of winter, though, the sun is too low in the sky to heat the water as we need it.
• As far as I can tell, both the solar panels and the supplementary electric heater heat water in the same boiler, the same container, and it is on the roof, where it gets cold in the winter -- not Wisconsin cold, but too cold for insulation to keep the water hot over night.
• A week ago at dawn, something exploded on the roof next door. Steam shot out from the cluster of boilers.
• If we leave the electric heater on all night, will our boiler explode?

Copyright 2006 Jane S. Fox