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TYPES OF SOLAR COLLECTORS

FROM THIS POINT ON, this book will deal with the nuts and bolts of solar water heating and space heating systems. We think it is appropriate to first let you know our perspective. We both live in Wisconsin, where the weather can be severe, particularly in regard to cold temperatures and snow that stays for months. Our experiences with solar thermal systems have been heavily influenced by the weather here. It is interesting to note that approximately 90 percent of the population of the world lives in a warmer climate than we do. Green Bay, Wisconsin, just 50 miles away from our homes and at the same latitude, is the coldest city in the continental US with a population over 100,000. The average coldest temperature in Wisconsin is–44°F. (The record is–56°F.) In a cold climate like this we have seen everything go wrong with a solar thermal system than can possibly happen because of cold weather. We also get a lot of snow each winter, and this snow typically stays on the ground and on roofs for at least four months without melting. Also know that it gets plenty hot here during the summer, so we have seen that side of things as well. The bottom line is that there is no room for error around here in either system design or installation, and this has influenced our perspective significantly.

So we are picky when it comes to system designs. If you follow our suggestions that are based on “worst-case scenarios” you will have success, even if you are in a warmer or less severe climate than ours. The next question is, are we suggesting designs that are overkill? The answer is no, because it does not actually cost more to design and install a system properly whether you are in a hot, cold or in-between type of climate. Having lived through the oil embargo years and the ensuing solar boom, we have seen many systems installed that were not appropriate for the local climate or were sub-standard in other ways. These systems required significant repair costs that, when added to the original cost of the system, resulted in a more costly system than systems that were properly designed and installed in the first place.