Ask This Old House plumbing and heating expert Richard Trethewey explains the complexities of today’s solar-power systems. (See below for steps.)
Steps for Understanding Solar Power:
1. Solar thermal panels are used to create domestic hot water. The panels are filled with antifreeze or evacuated tubes.
2. A typical thermal-panel system can produce 65 to 70 percent of a home’s hot water needs.
3. A photovoltaic (PV) system transforms the sun’s energy into direct current (DC) electricity.
4. An inverter mounted inside the house converts the DC power to standard alternating current (AC), which is then used to power lights, appliances, and other electrical devices.
5. If the PV system produces more electricity than you can use, the excess gets sent back to the power company and you receive a credit on your electric bill.
6. Solar companies are now offering power purchase agreements to homeowners, which include a free solar system in exchange for government rebates.