Photovoltaics (PV) is the process of creating electrical power by converting solar radiation into DC current electricity by using semiconductors that exhibit the photovoltaic effect. Photovoltaic power uses solar energy panels comprised of cells that contain the photovoltaic material.
Photovoltaics can involve a single cell however this is typically not the case, since a single cell cannot produce enough power. Generally the cells are electrically connected to form photovoltaic modules, or as we know them, solar energy panels.
Photovoltaic Effect – this involves the creation of voltage when a specific material is exposed to light. In this process, generated electrons bounce between different bands in the material causing a buildup of voltage (the junction of two substances exposed to light). This effect first observed by Alexandre-Edmond Becquerel.
Initially photovoltaics were used to power satellites and space stations orbiting in space, recently the majority is used for grid connected power generation for homes and businesses. With the development and implementation of electric cars, photovoltaics technologies continue to expand.
While there are many positives there are a few negatives. These would include cost and the fact that photovoltaics produce only DC current that must be converted. Secondly, current cannot be produced at night or when it is significantly cloudy. Solar power is also dependent on the limited power density of a locations insolation, a topic discussed in an earlier blog post.
Post written by: David Zamostny, Solar Energy World Intern
Technological advances, such as updates to the photovoltaic cell, continue to push solar energy forward and help it join mainstream society. Perhaps the largest breakthrough in thrusting solar energy onto the main stage was the invention of the modern silicon solar cell, which by all accounts, was a mistake.
Early inventions paved the way for the modern silicon cell, most notably by French physicist A. E. Becquerel in 1839 who discovered the photo-electric effect- the birth of the photovoltaic cell. It was in 1883 that the first cell was built by Charles Fritts. These cells used a layer of gold to form junctions and were about 1% efficient.
A few iterations later, the modern silicon cell was stumbled upon by Bell Labs in 1954. While researching semi-conductors, scientists realized that when silicon was combined with certain “impurities” it became highly sensitive to light.
Daryl Chapin, Calvin Fuller and Gerald Pearson, all of Bell Labs, converted the accidental discovery into the first practical device that converted sunlight into energy, the beginning of modern solar energy. Dubbed a solar battery, the first modern silicon cells debuted by powering a toy windmill and a radio, reaching an efficiency level of 6 percent.
The silicon cells became the basis for launching the solar energy industry. One year later, Western Electric licensed commercial solar cell technologies, and in 1957 the three scientist received a U.S. patent for a “Solar Energy Converting Apparatus.”
Shortly thereafter, in March of 1958, the scientists at Bell Labs reached true “stardom,” as the U.S. satellite Vangard I was launched with solar panels. This use of solar energy helped to spur government investment into solar energy, further bolstering the creation of the solar energy industry.
Today, new technology is starting to eclipse the use of the silicon cell, but many solar panels you see still use, or are based on, the silicon cell model as a means of converting natural sunlight into clean energy.
You might think that commercial solar arrays are expensive. The reality is this: it’s costly NOT to go solar. Here’s the breakdown (what you’re missing!):
- The typical ROI (return on investment) is between 12-30%!
- The federal government subsidizes your system by 30% (uncapped)
- The state of Maryland (as an example) offers up to $2.5 million per system in tax incentives, and many counties in the state also offer credits or grants. Other states offer credits and grants as well.
- Increase the resale value significantly without adding to property tax liability
- Write off 100% depreciation in the first year
- Reduction in operating costs while electricity costs skyrocket throughout the country
- “Hedge” against the rising energy costs
- Promote your business’ efforts at going green
Business owners also have options to meet their needs, as Solar Energy World offers a type of “rent-to-own” option called “Power Purchase Agreements” or the ability to own your own system and fast-track MAXIMUM savings and earnings.
Remember, “Go green, save green!“