How Solar Energy Works

The San Diego solar energy industry is aglow right now.  The Department of Energy offered a partial loan guarantee last week that will fund Project Amp, a $1.4 billion plan that will put photovoltaic panels on rooftops all over the United States.  The panels are to be installed on the rooftops of warehouse buildings in 28 states run by Project Amp's co-owner, Prologis.  A loan guarantee for $1.4 billion project is a pretty big deal, so let's find out what this solar energy hype is all about.

How It Works

Photovoltaic energy (solar energy) works off of sunlight.  Photovoltaic (PV) cells, or solar panels, are made of two slices of silicon.  One is positively charged and the other negatively charged, both enclosed together in glass casing with a metal frame.  Silicon is commonly used in PV cells because it is a semi-conductor.  The space between the two opposite charged slices is called the P-N junction, which allows electrons to pass from one slice to the other.  When sunlight hits the cell, it knocks electrons off the positively charged silicon and they move toward the negatively charged slice.  Electrons from the negatively charged silicon can only travel to the positive side if there is an internal circuit.  In the PV cell, thin wire on the negative silicon catches the free electrons, creates an internal circuit and creates electrical current.  When connected to an external electrical circuit, the current can be used to power your home.  According to the experts in solar electric San Diego, Solaire Energy Systems, any leftover electricity is sent back to your local power company grid and stored as a 'credit' for you to use during non-daylight hours.

Stay tuned to find out how installing solar panels benefit you, your home and the environment.
Suggested Reading: How Much Do Solar Panels Cost?