I'll explain how a solar heater works. They basically take the water from your house and run it through very thin tubes in a panel on your roof. During that stage the sun heats up the water and it is taken back into your house were it comes out of your faucet and/or sink. A solar heating system for air consists of a pump, a ventilation system, and a window facing the sun. The pump will force air into the ventilation system which runs behind the window facing the sun. Then the sun heats the air and its then pumped through your home for your comfort in cold times. Most solar heating systems pay for themselves with in 4-8 years.