Local Knowledge About Active Solar Space Heating

Solar systems should be employed only after extensive conservation strategies have been implemented. Solar energy systems typically have a high initial cost and extremely low operating costs. To reduce the high initial costs, reduce the size of the required system by the load that the solar system will need to provide. In space heating applications, the home should be weatherized and insulated to very high standards. The goal of the solar system should not be to accomplish 100% of the home's heating or water heating needs under all conditions. The system should be sized to reflect seasonal variations in demand and in the sun's heating characteristics. Additionally, by combining systems to perform multiple functions (i.e. space heating and water heating), the solar system investment can provide a return all year. Active solar energy systems are usually designed to provide from 40% to 80% of a home's yearly heating needs. But, data from systems installed through a government demonstration program indicates that active space heating systems are most economical when they are designed to handle about 50% of a home's heating requirements. A system sized to provide much more than this would not be economical since some of the extra capacity would only be used during the coldest days. The rest of the time, the extra equipment would be idle.