Solar Panels

         TIME TO SWITCH ON TO ALTERNATIVE ENERGY

Lets generate own electricity and enjoy uninterrupted power supply everyday. Virtually unlimited power is available from our nearest star, the Sun. In just one hour, our planet receives more energy from the sun than the entire world uses during an entire year. Electricity-producing solar panels have only been around for the last 60 years, yet they have completely transformed how we harness solar energy.

In 1839, a nineteen year-old French physicist named Alexandre-Edmond Becquerel discovered the operating principle of the solar cell, known as the photovoltaic effect. It wasn’t until 1876 that this effect materialized into a viable method of producing electricity with the work of William Grylls Adams. He discovered that by illuminating a junction between selenium and platinum, a photovoltaic effect occurs; electricity could now be produced without moving parts.

Revolutionary as they may have been, the selenium solar cells were not efficient enough to power electrical equipment. That ability occurred in 1953 when a Bell Laboratories employee Gerald Pearson had the bright idea of making a solar cell with silicon instead of selenium. The New York Times heralded the discovery as “The beginning of a new era, leading eventually to the realization of harnessing the almost limitless energy of the sun for the uses of civilization”.

Just in time for the space race, the first solar panels made their debut in the satellite industry. Vanguard I, the first solar-powered satellite celebrated its 53rd birthday this year, setting mileage records and holding the title of being the oldest artificial satellite still in orbit.

The first solar modules were only efficient enough for space applications, where the Sun’s radiation is much stronger. Eventually satellite research paved the way for Earth-based technology. The 1990’s were pivotal years for photovoltaic technology. Innovations in solar cells allowed for greater efficiency while lowering the cost of production. Germany and Japan led the way with long-term solar power incentive programs helping lower the cost to the public, and spurring the growth of a robust Photovoltaic industry in both countries.

In 2006, California made a major long-term commitment to solar power by passing the California Solar Initiative, a ten-year incentive program with the goal of installing 3,000 megawatts of solar panels on the equivalent of one million rooftops. California leads the nation in solar panel installations, as it currently has more photovoltaic systems installed than any other state. This incredible boom has taken place mostly due to California’s Renewable Portfolio Standard, which requires that 20 percent of the state’s electricity come from renewable resources by 2010. In 2008 the state decided that it was not moving fast enough in meeting these goals and enacted a feed-in tariff, requiring utility companies to buy back excess power produced by homeowner’s and private photovoltaic installations. In the same year, the state also raised the Renewable Portfolio Standard to 33 percent by 2020, greatly helping spur growth in the renewable energy industry.

How Solar Panels work

Photovoltaic solar modules are composed of multiple, interconnected solar cells, which effectively trap photon energy between layers of silicon wafers. Negatively charged electrons are then knocked loose from their atoms, allowing them to flow freely through the semiconductors. Separate diodes, and P-N junctions prevent reverse currents and reduce loss of power on partially shaded panels.

Since the flow of electrical current is going in one direction, like a battery, the electricity generated is called direct current (DC). Sunlight conversion rates are typically in the 5 to 18 percent range, with some laboratory experiments reaching efficiencies as high as 30 percent. Future possibilities include the development of multi-junction solar cells that are capable of harnessing a wider bandwidth of useable light. We are still considered to be in the “early” stages of solar cell technology.

Off Grid versus Grid tied

Solar panels are used extensively in rural areas, where access to the grid is non-existent or inaccessible. These installations are called off grid (or independent, stand-alone) solar power systems, and require the use of batteries to store the energy for use at night or on long stretches of overcast weather. The energy stored in the batteries leaves the batteries as DC electricity which can power DC appliances (as in RV’s) or be converted to alternating current (AC) for use with conventional appliances. Much like running your own mini utility company, this method gives you full independence from the national grid.

You can eliminate the cost of batteries by going with a system that connects right into your home’s main junction box and use the grid as your power source at night or on long stretches of inclement weather. These installations are known as grid-tied or grid-interconnected systems. This version of solar system enables you to sell any excess power you produce back to the utility companies who have chosen to support “net metering”. Once you are signed up on a net metering program, your utility company will have a smart meter installed known as a Time of Use Meter, which will actually run backwards when you are producing excess power. It is wise to keep in mind that Grid tied systems without a battery backup, are only functional when the grid is operational. Due to anti-islanding features on grid tied inverters, which protect utility workers from working on a live line, grid-tied systems without a battery back up will not continue to produce power during a power outage regardless of whether you have sunshine or not.

Since solar panels produce DC, or direct current, they must be coupled with a solar inverter to convert the energy from DC to AC, or alternating current. In a grid tied system this can be done by a large central inverter, or each solar panel can be outfitted with its own micro inverter. Once the power is converted to alternating current and its phase is synchronized with that of the grid, it is then tied in to your main junction box, which is ultimately interconnected to the national grid.

TYPES OF SOLAR PANELS THAT WE CAN OFFER YOU ARE:

mono-crystalline (single crystal)

poly-crystalline (multiple crystals)

or

amorphous silicon

IF YOU’RE INTERESTED AND WANT MORE INFORMATION ON SOLAR PANELS ALONG WITH QUOTATIONS OR THINKING OF STARTING A JOINT VENTURE, SIMPLY EMAIL YOUR QUERIES AT: info@zafarson.com