Solar energy is becoming an important renewable energy source as petroleum-based resources become more expensive and as concerns over carbon emissions from coal-fired power plants and the danger of nuclear power plants escalate. Solar energy information is now abundant, and solar technology is growing as more and more people put solar energy to work.

Before reading on about how solar panels work, you may be interested in:

Residential Solar Energy: Using the Sun's Energy to Power Your Home,

Solar Energy Advantages: 5 Reasons to Go Solar or

Five Ways to Use Alternative Solar Energy at Home

So, how do solar panels work? Solar panels are composed of solar cells, also called photovoltaic (PV) cells, connected together.  PV cells are made of a semi-conducting material, usually silicon. When sunlight strikes the surface of a solar cell, it excites electrons, causing them to jump to the other side of the cell and creating an electric current. Each solar cell generates only about half of a volt, so several cells are connected within a panel to generate enough voltage to be functional. 

Multiple PV panels can be connected in series or in parallel to generate more power for use in homes, schools, office buildings or for municipal power generation. Wiring in series results in higher voltage and lower current, while wiring in parallel results in lower voltage with a higher current. 

In order for solar power to be a cost effective source of power, certain conditions must exist. The PV panel must be orientated to face the sun.  If a roof slopes to the east and west, it is not ideal for mounting solar panels. South facing roof slopes are ideal for optimal power generation. Also, sites for panel installation must receive several hours of direct sunlight every day.  Even a small amount of shading by trees or buildings reduces panel efficiency significantly. Some PV panels, particularly those made with thin-film technology, are able to generate power without direct sunlight, but just diffuse, ambient light. 

Photovoltaic panels and a solar energy system are  smart investments for generating energy. After the initial investment, operation is virtually free. Not only that, choosing solar is an environmentally responsible and cost-effective way to save energy and money.