Simply because a very large energy flux falls on the Britain through the year, it is wrongly (1) _____ by many that the life to which they (2) _____ can be supported with solar energy.Even with the reduced level of energy use we managed to achieve with proper insulation, the average level of radiation occurring during the two months when we need warmth most—December and January—is (3) _____ to an average of 15 watts per square meter.This is extremely small.To (4) _____ any use of such small radiation requires that very large areas be (5) _____ to low-temperature collection, (6) _____ will be redundant during the summer months when average radiation, over the month of June for example, is 225 watts per square meter.Thus, unless you can set side at least 40 square meters of cheap solar collecting surface, facing due south at an angle of around 70 (7) _____ the horizontal, it is best to forget energy self-sufficiency from the sun alone.

　　It is not so silly, however, to use the sun when it does shine hot to provide between 50% and 90% of your hot water, usually during the months of April to September when it is warm enough.4 square meters of collecting surface (8) _____ the hot-water system of your house can provide up to 100kwh/m per month.At 2p per kwh, which is the price we (9) _____ be paying soon, it would be (10) _____ $48 a year.