Nineteenth-century French physicist Edmond Becquerel was fascinated with the study of light. He was particularly interested in the characteristics of solar radiation. In 1839, Becqueral discovered the photovoltaic (PV) effect, the ability of certain substances to generate electricity when exposed to sunlight.
Today, the term “photovoltaic” is used to describe solar energy systems. Advancements in modern technology combined with lower prices and solar financing options are making residential and commercial PV energy systems practical solutions for augmenting electrical generation for homes and businesses. Generous incentive programs offered at the federal, state and local level are also making solar energy more affordable.
PV System Components
In modern PV generation, the devices used to harness the energy of the sun are called solar cells. The material in solar cells ejects electrons when they come into contact with solar radiation, generating energy. Solar cells are linked together and housed in glass-covered framed structures called solar panels.
Most solar panel arrays are placed on the building’s roof to give the array the best possible exposure to the sun. Ground-mounted arrays are also available. Some ground-mounted systems are motorized to tilt the panels towards the sun as it travels across the sky.
Because the electricity that PV energy systems produce is direct current, an inverter is needed to transform the energy into the alternate current that homes and businesses use. The inverter is typically housed near the building’s electrical meter, either indoors or outside.
Grid-Connected Solar Energy Systems
Unlike self-sustaining PV systems, which require large, heavy-duty batteries to store the generated electricity, grid-connected solar energy systems are designed to work with the existing energy grid. Whenever a PV system isn’t generating enough electricity to meet the demands of the home or business, conventional electricity automatically augments the system.
When residential or commercial PV systems generate more electricity than the building is currently using, the surplus energy is sent into the local electrical grid. Most states require utilities to compensate PV system owners for the surplus electricity. Compensation may come in the form of a credit on the electric bill, may be issued as a refund check or may be awarded as a Solar Renewable Energy Credit, a financial instruments that may be sold through utility markets.
Solar Financing Options
Many home and business owners choose to purchase their PV systems outright. Installation costs are recouped through incentives and monthly savings on their electric bills. Solar financing options are available for those for whom the upfront costs are a deterrent. Solar leases are by far the most popular option.
With a solar lease, the PV provider purchases the system and then leases it to the home or business owner. The provider arranges for the PV system’s installation, insures the system and maintains it. In return, the home or business owner pays the provider for the electricity that the PV system generates. Because solar-generated electricity is much cheaper than conventional electricity, the owner saves money on energy bills while enjoying clean, green solar energy.