1. By Brenda Ruedas && Coralann Stell

2. -- The gathering of solar energy by collectors that are used to heat water or heat a building … ACTIVE SOLAR HEATING

3. A liquid is heated by the sun as it flows through the solar collectors. The hot liquid is then pumped through a heat exchanger, which heats water for the building.

4. -- More than 1 million homes in the U.S use active solar energy to heat water ….. -- About 8 % of the energy used in the US is used to heat water ; therefore, active solar technology could save a lot of energy …