Photovoltaics (PV) is the conversion of light into electricity using semiconducting materials that exhibit the photovoltaic effect, a phenomenon studied in physics, photochemistry, and electrochemistry. The photovoltaic effect is commercially used for electricity generation and as photosensors.
The National Renewable Energy Laboratory (NREL) in the US specializes in the research and development of renewable energy, energy efficiency, energy systems integration, and sustainable transportation. NREL is a federally funded research and development center sponsored by the Department of Energy and operated by the Alliance for Sustainable Energy, a joint venture between MRIGlobal and Battelle. Located in Golden, Colorado, NREL is home to the National Center for Photovoltaics, the National Bioenergy Center, and the National Wind Technology Center.
The photovoltaic effect is the generation of voltage and electric current in a material upon exposure to light. It is a physical and chemical phenomenon.
A solar cell or photovoltaic cell is an electronic device that converts the energy of light directly into electricity by means of the photovoltaic effect. It is a form of photoelectric cell, a device whose electrical characteristics vary when exposed to light. Individual solar cell devices are often the electrical building blocks of photovoltaic modules, known colloquially as "solar panels". The common single-junction silicon solar cell can produce a maximum open-circuit voltage of approximately 0.5 to 0.6 volts.
Charles Fritts was the American inventor credited with creating the first working selenium cell in 1883.
A solar panel is a device that converts sunlight into electricity by using photovoltaic (PV) cells. PV cells are made of materials that generate electrons when exposed to light. The electrons flow through a circuit and produce direct current (DC) electricity, which can be used to power various devices or be stored in batteries. Solar panels are also known as solar cell panels, solar electric panels, or PV modules.
Nanosolar was a developer of solar power technology. Based in San Jose, CA, Nanosolar developed and briefly commercialized a low-cost printable solar cell manufacturing process. The company started selling thin-film CIGS panels mid-December 2007, and planned to sell them at 99 cents per watt, much below the market at the time. However, prices for solar panels made of crystalline silicon declined significantly during the following years, reducing most of Nanosolar's cost advantage. By February 2013 Nanosolar had laid off 75% of its work force. Nanosolar began auctioning off its equipment in August 2013. Co-Founder of Nanosolar Martin Roscheisen stated on his personal blog that nanosolar "ultimately failed commercially." and that he would not enter this industry again because of slow-development cycle, complex production problems and the impact of cheap Chinese solar power production. Nanosolar ultimately produced less than 50 MW of solar power capacity despite having raised more than $400 million in investment.
Building-integrated photovoltaics (BIPV) are photovoltaic materials that are used to replace conventional building materials in parts of the building envelope such as the roof, skylights, or façades. They are increasingly being incorporated into the construction of new buildings as a principal or ancillary source of electrical power, although existing buildings may be retrofitted with similar technology. The advantage of integrated photovoltaics over more common non-integrated systems is that the initial cost can be offset by reducing the amount spent on building materials and labor that would normally be used to construct the part of the building that the BIPV modules replace. In addition, BIPV allows for more widespread solar adoption when the building's aesthetics matter and traditional rack-mounted solar panels would disrupt the intended look of the building.
First Solar, Inc. is an American manufacturer of solar panels, and a provider of utility-scale PV power plants and supporting services that include finance, construction, maintenance and end-of-life panel recycling. First Solar uses rigid thin-film modules for its solar panels, and produces CdTe panels using cadmium telluride (CdTe) as a semiconductor. The company was founded in 1990 by inventor Harold McMaster as Solar Cells, Inc. and the Florida Corporation in 1993 with JD Polk. In 1999 it was purchased by True North Partners, LLC, who rebranded it as First Solar, Inc.
Solar power is the conversion of energy from sunlight into electricity, either directly using photovoltaics (PV) or indirectly using concentrated solar power. Photovoltaic cells convert light into an electric current using the photovoltaic effect. Concentrated solar power systems use lenses or mirrors and solar tracking systems to focus a large area of sunlight to a hot spot, often to drive a steam turbine.
A photovoltaic system, also PV system or solar power system, is an electric power system designed to supply usable solar power by means of photovoltaics. It consists of an arrangement of several components, including solar panels to absorb and convert sunlight into electricity, a solar inverter to convert the output from direct to alternating current, as well as mounting, cabling, and other electrical accessories to set up a working system. It may also use a solar tracking system to improve the system's overall performance and include an integrated battery.
Cadmium telluride (CdTe) photovoltaics is a photovoltaic (PV) technology based on the use of cadmium telluride in a thin semiconductor layer designed to absorb and convert sunlight into electricity. Cadmium telluride PV is the only thin film technology with lower costs than conventional solar cells made of crystalline silicon in multi-kilowatt systems.
Thin-film solar cells are made by depositing one or more thin layers of photovoltaic material onto a substrate, such as glass, plastic or metal. Thin-film solar cells are typically a few nanometers (nm) to a few microns (µm) thick–much thinner than the wafers used in conventional crystalline silicon (c-Si) based solar cells, which can be up to 200 µm thick. Thin-film solar cells are commercially used in several technologies, including cadmium telluride (CdTe), copper indium gallium diselenide (CIGS), and amorphous thin-film silicon.
A copper indium gallium selenide solar cell is a thin-film solar cell used to convert sunlight into electric power. It is manufactured by depositing a thin layer of copper indium gallium selenide solid solution on glass or plastic backing, along with electrodes on the front and back to collect current. Because the material has a high absorption coefficient and strongly absorbs sunlight, a much thinner film is required than of other semiconductor materials.
Concentrator photovoltaics (CPV) is a photovoltaic technology that generates electricity from sunlight. Unlike conventional photovoltaic systems, it uses lenses or curved mirrors to focus sunlight onto small, highly efficient, multi-junction (MJ) solar cells. In addition, CPV systems often use solar trackers and sometimes a cooling system to further increase their efficiency.
There are currently many research groups active in the field of photovoltaics in universities and research institutions around the world. This research can be categorized into three areas: making current technology solar cells cheaper and/or more efficient to effectively compete with other energy sources; developing new technologies based on new solar cell architectural designs; and developing new materials to serve as more efficient energy converters from light energy into electric current or light absorbers and charge carriers.
Solar-cell efficiency refers to the portion of energy in the form of sunlight that can be converted via photovoltaics into electricity by the solar cell.
Amonix, Inc. is a solar power system developer based in Seal Beach, California. The company manufactures concentrator photovoltaic (CPV) products designed for installation in sunny and dry climates. CPV products convert sunlight into electrical energy in the same way that conventional solar photovoltaic technology does, except that they use optics to focus the solar radiation before the light is absorbed by solar cells. According to a comparative study of energy production of solar technologies, CPV systems require no water for energy production and produce more energy per megawatt (MW) installed than traditional PV systems. Amonix has nearly 70 megawatts of CPV solar power systems deployed globally, including Southwestern U.S. and Spain. In May 2012, the Alamosa Solar Generating project, owned and operated by Cogentrix Energy, began commercial operation. This is the largest CPV power plant in the world and is expected to produce enough clean renewable energy per year to power more than 6,500 homes and will avoid the emissions of over 43,000 metric tons of carbon dioxide per year. The Alamosa Solar Generating Project is supported by a power purchase agreement (PPA), which is a long-term agreement to sell the power it will generate. Under the project's PPA, the Public Service Company of Colorado will buy the power generated by the solar facility for the next 20 years. In July 2012, Amonix set the world record for photovoltaic module efficiency at 33.5% under nominal operating conditions, verified by the National Renewable Energy Laboratory. In April 2013, Amonix broke the record set in July 2012, demonstrating photovoltaic module efficiency at 34.9% under normal concentrator standard operating conditions, also verified by the National Renewable Energy Laboratory. In August 2013, Amonix announced it had achieved a 35.9% photovoltaic module efficiency rating under concentrator standard test conditions (CSTC) as calculated by NREL. In June, 2014, the assets of Amonix were acquired by Arzon Solar, LLC for the purpose of continued development of CPV technology and products.
There are many practical applications for solar panels or photovoltaics. From the fields of the agricultural industry as a power source for irrigation to its usage in remote health care facilities to refrigerate medical supplies. Other applications include power generation at various scales and attempts to integrate them into homes and public infrastructure. PV modules are used in photovoltaic systems and include a large variety of electrical devices.
Emily Warren is an American chemical engineer who is a staff scientist at the National Renewable Energy Laboratory. Her research considers high efficiency crystalline photovoltaics.
