Bole solar collectors are much more affordable than many other solar hot water heaters. For a household of 4, the price of a full system may not be too much more than a new electric or gas system. Depending on you location (solar levels) and current hot water usage the annual electricity or gas saving will differ. However in a normal household that spends 25% of its electricity bill on hot water heating, the full cost of the purchase may be recouped as quickly as 4-5 years in reduced bills. You will definitely make considerable savings during the life of the solar hot water heater.