What do Archimedes, Einstein, and Arnold Schwarzenegger all have in common? Answer: They've all contributed to the development of solar power...
History of Solar Cells
Solar technology isn't new. Its history spans from the 7th Century B.C. to today. We started out concentrating the sun's heat with glass and mirrors to light fires. Today, we have everything from solar-powered buildings to solar-powered vehicles.
Here you can learn more about the milestones in the historical development of solar technology, century by century, and year by year. You can also glimpse the future.
7th Century B.C.
Magnifying glass used to concentrate sun's rays to make fire and to burn ants.
3rd Century B.C.
Greeks and Romans use burning mirrors to light torches for religious purposes.
2nd Century B.C.
As early as 212 BC, the Greek scientist, Archimedes, used the reflective properties of bronze shields to focus sunlight and to set fire to wooden ships from the Roman Empire which were besieging Syracuse. (Although no proof of such a feat exists, the Greek navy recreated the experiment in 1973 and successfully set fire to a wooden boat at a distance of 50 meters.)
20 A.D.
Chinese document use of burning mirrors to light torches for religious purposes
1st to 4th Century A.D
The famous Roman bathhouses in the first to fourth centuries A.D. had large south facing windows to let in the sun's warmth.
6th Century A.D.
Sun-rooms on houses and public buildings were so common that the Justinian Code initiated “sun rights” to ensure individual access to the sun.
1200s A.D.
Ancestors of Pueblo people called Anasazi in North America live in south-facing cliff dwellings that capture the winter sun.
1767
Swiss scientist Horace DE Saussure was credited with building the world's first solar collector, later used by Sir John Herschel to cook food during his South Africa expedition in the 1830s. See the Solar Cooking Archive for more information on Sassure and His Hot Boxes of the 1700s.
1816
On September 27, 1816, Robert Stirling applied for a patent for his economizer at the Chancery in Edinburgh, Scotland. By trade, Robert Stirling was a minister in the Church of Scotland and he continued to give services until he was eighty-six years old! But, in his spare time, he built heat engines in his home workshop. Lord Kelvin used one of the working models during some of his university classes. This engine was later used in the dish/Stirling system, a solar thermal electric technology that concentrates the sun’s thermal energy to produce power.
1839
French scientist Edmond Becquerel discovers the photo-voltaic effect while experimenting with an electrolytic cell made up of two metal electrodes placed in an electricity-conducting solution—electricity-generation increased when exposed to light.
1860s
French mathematician August Mouchet proposed an idea for solar-powered steam engines. In the following two decades, he and his assistant, Abel Pifre, constructed the first solar-powered engines and used them for a variety of applications. These engines became the predecessors of modern parabolic dish collectors.
1873
Willoughby Smith discovered the photo-conductivity of selenium.
1876
876 William Grylls Adams and Richard Evans Day discover that selenium produces electricity when exposed to light. Although selenium solar cells failed to convert enough sunlight to power electrical equipment, they proved that a solid material could change light into electricity without heat or moving parts.
1880
Samuel P. Langley invents the bolometer, which is used to measure light from the faintest stars and the sun’s heat rays. It consists of a fine wire connected to an electric circuit. When radiation falls on the wire, it becomes very slightly warmer. This increases the electrical resistance of the wire.
1883
Charles Fritts, an American inventor, described the first solar cells made from selenium wafers.
1887
Heinrich Hertz discovered that ultraviolet light altered the lowest voltage capable of causing a spark to jump between two metal electrodes.
1891
Baltimore inventor Clarence Kemp patented the first commercial solar water heater. For more information on the water heater, see the California Solar Center.
1767
Swiss scientist Horace DE Saussure was credited with building the world's first solar collector, later used by Sir John Herschel to cook food during his South Africa expedition in the 1830s. See the Solar Cooking Archive for more information on Sassure and His Hot Boxes of the 1700s.
1904
Wilhelm Hallwachs discovered that a combination of copper and cuprous oxide is photosensitive.
1905
Albert Einstein published his paper on the photoelectric effect (along with a paper on his theory of relativity).
1908
1908 William J. Bailley of the Carnegie Steel Company invents a solar collector with copper coils and an insulated box—roughly, it's present design.
1914
The existence of a barrier layer in photo-voltaic devices was noted.
1916
Robert Millikan provided experimental proof of the photoelectric effect.
1918
Polish scientist Jan Czochralski developed a way to grow single-crystal silicon. For more information on Czochralski, see the article Professor Jan Czolchralski (1885-1953) and His Contribution to the Art and Science of Crystal Growth.
1921
Albert Einstein wins the Nobel Prize for his theories (1904 research and technical paper) explaining the photoelectric effect.
1932
Audobert and Stora discover the photo-voltaic effect in cadmium sulfide (CdS).
1947
1947 Passive solar buildings in the United States were in such demand, as a result of scarce energy during the prolonged W.W.II, that Libbey-Owens-Ford Glass Company published a book entitled Your Solar House, which profiled forty-nine of the nation's greatest solar architects.
1953
Dr. Dan Trivich, Wayne State University, makes the first theoretical calculations of the efficiencies of various materials of different band gap widths based on the spectrum of the sun.
1954 - The Birth of Photo-voltaic's
1954 Photo-voltaic technology is born in the United States when Daryl Chapin, Calvin Fuller, and Gerald Pearson develop the silicon photo-voltaic (PV) cell at Bell Labs—the first solar cell capable of converting enough of the sun's energy into power to run everyday electrical equipment. Bell Telephone Laboratories produced a silicon solar cell with 4% efficiency and later achieved 11% efficiency.
1955
Western Electric began to sell commercial licenses for silicon photo-voltaic (PV) technologies. Early successful products included PV-powered dollar bill changers and devices that decoded computer punch cards and tape.
Mid-1950s
Architect Frank Bridgers designed the world's first commercial office building using solar water heating and passive design. This solar system has been continuously operating since that time and the Bridgers-Paxton Building, is now in the National Historic Register as the world’s first solar heated office building.
1956
William Cherry, U.S. Signal Corps Laboratories, approaches RCA Labs' Paul Rappaport and Joseph Loferski about developing photo-voltaic cells for proposed orbiting Earth satellites.
1957
Hoffman Electronics achieved 8% efficient photo-voltaic cells.
1958
T. Mandelkorn, U.S. Signal Corps Laboratories, fabricates n-on-p silicon photo-voltaic cells (critically important for space cells; more resistant to radiation).
1958
Hoffman Electronics achieves 9% efficient photo-voltaic cells.
1958
The Vanguard I space satellite used a small (less than one watt) array to power its radios. Later that year, Explorer III, Vanguard II, and Sputnik-3 were launched with PV-powered systems on board. Despite faltering attempts to commercialize the silicon solar cell in the 1950s and 60s, it was used successfully in powering satellites. It became the accepted energy source for space applications and remains so today. For more information, see the Smithsonian National Air and Space Museum's information on 'Vanguard 1'.
1959
Hoffman Electronics achieves 10% efficient, commercially available photo-voltaic cells. Hoffman also learns to use a grid contact, reducing the series resistance significantly.
1959
On August 7, the Explorer VI satellite is launched with a photo-voltaic array of 9600 cells (1 cm x 2 cm each). Then, on October 13, the Explorer VII satellite is launched.
1960
Hoffman Electronics achieves 14% efficient photo-voltaic cells.
1960
Silicon Sensors, Inc., of Dodgeville, Wisconsin, is founded. It starts producing selenium and silicon photo-voltaic cells.
1962
Bell Telephone Laboratories launches the first telecommunications satellite,the Telstar (initial power 14 watts).
1963
Sharp Corporation succeeds in producing practical silicon photo-voltaic modules.
1963
Japan installs a 242-watt, photo-voltaic array on a lighthouse, the world's largest array at that time.
1964
NASA launches the first Nimbus spacecraft-a satellite powered by a 470-watt photo-voltaic array.
1965
Peter Glaser conceives the idea of the satellite solar power station.
1964
NASA launches the first Nimbus spacecraft-a satellite powered by a 470-watt photo-voltaic array.
1966
NASA launches the first Orbiting Astronomical Observatory, powered by a 1-kilowatt photo-voltaic array, to provide astronomical data in the ultraviolet and X-ray wavelengths filtered out by the earth's atmosphere.
1969
The Odeillo solar furnace, located in Odeillo, France was constructed. This featured an 8-story parabolic mirror.
1970s
Dr. Elliot Berman, with help from Exxon Corporation, designs a significantly less costly solar cell, bringing the price down from $100 a watt to $20 a watt. Solar cells begin to power navigation warning lights and horns on many offshore gases and oil rigs, lighthouses, and railroad crossings and domestic solar applications began to be viewed as sensible applications in remote locations where grid-connected utilities could not exist affordably.
1972
The French install a cadmium sulfide (CdS) photo-voltaic system to operate an educational television at a village school in Niger.
1972
The Institute of Energy Conversion is established at the University of Delaware to perform research and development on thin-film photo-voltaic (PV) and solar thermal systems, becoming the world's first laboratory dedicated to PV research and development.
1973
The University of Delaware builds 'Solar One,' one of the world's first photo-voltaic (PV) powered residences. The system is a PV/thermal hybrid. The roof-integrated arrays fed surplus power through a special meter to the utility during the day and purchased power from the utility at night. In addition to electricity, the arrays acted as flat-plate thermal collectors, with fans blowing the warm air from over the array to phase-change heat-storage bins.
1976
The NASA Lewis Research Center starts installing 83 photo-voltaic power systems on every continent except Australia. These systems provide such diverse applications as vaccine refrigeration, room lighting, medical clinic lighting, telecommunications, water pumping, grain milling, and classroom television. The Center completed the project in 1995, working on it from 1976-1985 and then again from 1992-1995.
1976
David Carlson and Christopher Wronski, RCA Laboratories, fabricate first amorphous silicon photo-voltaic cells.
1977
Total photo-voltaic manufacturing production exceeds 500 kilowatts.
1978
1978 NASA's Lewis Research Center dedicates a 3.5-kilowatt photo-voltaic (PV) system it installed on the Papago Indian Reservation located in southern Arizona-the world's first village PV system. The system is used to provide water pumping and residential electricity in 15 homes until 1983 when grid power reached the village. The PV system was then dedicated to pumping water from a community well.
1980
ARCO Solar becomes the first company to produce more than 1 megawatt of photo-voltaic modules in one year.
1980
At the University of Delaware, the first thin-film solar cell exceeds 10% efficiency using copper sulfide/cadmium sulfide.
1981
Paul MacCready builds the first solar-powered aircraft-the Solar Challenger-and flies it from France to England across the Channel. The aircraft had over 16,000 solar cells mounted on its wings, which produced 3,000 watts of power. The Smithsonian Institute National Air and Space Museum has a photo of the ' Solar Challenger' in flight.
1982
The first, photo-voltaic megawatt-scale power station goes on-line in Hesperia, California. It has a 1-megawatt capacity system, developed by ARCO Solar, with modules on 108 dual-axis trackers.
1982
Australian Hans Tholstrup drives the first solar-powered car—the Quiet Achiever—almost 2,800 miles between Sydney and Perth in 20 days-10 days faster than the first gasoline-powered car to do so. Tholstrup is the founder of the “World Solar Challenge” in Australia, considered the world championship of solar car racing.
1982
The U.S. Department of Energy, along with an industry consortium, begins operating Solar One, a 10-megawatt central-receiver demonstration project. The project established the feasibility of power-tower systems, a solar-thermal electric or concentrating solar power technology. In 1988, the final year of operation, the system could be dispatched 96% of the time. 'Concentrating Solar Power: Energy From Mirrors' and 'Solar Two Demonstrates Clean Power for the Future'.
1982
Volkswagen of Germany begins testing photo-voltaic arrays mounted on the roofs of Dasher station wagons, generating 160 watts for the ignition system.
1982
Worldwide photo-voltaic production exceeds 9.3 megawatts.
1983
Worldwide photo-voltaic production exceeds 21.3 megawatts, with sales of more than $250 million.
1985
The University of South Wales breaks the 20% efficiency barrier for silicon solar cells under 1-sun conditions.
1986
1986 The world's largest solar thermal facility, located in Kramer Junction, California, was commissioned. The solar field contained rows of mirrors that concentrated the sun's energy onto a system of pipes circulating a heat transfer fluid. The heat transfer fluid was used to produce steam, which powered a conventional turbine to generate electricity.
1986
ARCO Solar releases the G-4000-the world's first commercial thin-film power module.
1988
Dr. Alvin Marks receives patents for two solar power technologies he developed: Lepcon and Lumeloid. Lepcon consists of glass panels covered with a vast array of millions of aluminum or copper strips, each less than a micron or thousandth of a millimeter wide. As sunlight hits the metal strips, the energy in the light is transferred to electrons in the metal, which escape at one end in the form of electricity. Lumeloid uses a similar approach but substitutes cheaper, film-like sheets of plastic for the glass panels and covers the plastic with conductive polymers, long chains of molecular plastic units.
1992
University of South Florida develops a 15.9% efficient thin-film photo-voltaic cell made of cadmium telluride, breaking the 15% barrier for the first time for this technology.
1992
A 7.5-kilowatt prototype dish system using an advanced stretched-membrane concentrator becomes operational.
1993
1993 Pacific Gas & Electric completes installation of the first grid-supported photo-voltaic system in Kerman, California. The 500-kilowatt system was the first “distributed power” effort.
1994
First solar dish generator using a free-piston Stirling engine is tied to a utility grid.
1994
The National Renewable Energy Laboratory develops a solar cell-made from gallium indium phosphide and gallium arsenide-that becomes the first one to exceed 30% conversion efficiency.
1996
The world's most advanced solar-powered airplane, the Icare, flew over Germany. The wings and tail surfaces of the Icare are covered by 3,000 super-efficient solar cells, with a total area of 21 m2. See “Solar Aircraft of the University of Stuttgart” for more information about Icare.
1996
The U.S. Department of Energy, along with an industry consortium, begins operating Solar Two-an upgrade of its Solar One concentrating solar power tower project. Operated until 1999, Solar Two demonstrated how solar energy can be stored efficiently and economically so that power can be produced even when the sun isn't shining. It also fostered a commercial interest in power towers.
1998
The remote-controlled, solar-powered aircraft, “Pathfinder” sets an altitude record, 80,000 feet, on its 39th consecutive flight on August 6, in Monrovia, California. This altitude is higher than any prop-driven aircraft thus far.
1998
Subhendu Guha, a noted scientist for his pioneering work in amorphous silicon, led the invention of flexible solar shingles, a roofing material and state-of-the-art technology for converting sunlight to electricity.
1999
1999 Construction was completed on 4 Times Square, the tallest skyscraper built in the 1990s in New York City. It incorporates more energy-efficient building techniques than any other commercial skyscraper and also includes building-integrated photo-voltaic (BIPV) panels on the 37th through 43rd floors on the south and west-facing facades that produce a portion of the building's power.
1999
Spectrolab, Inc. and the National Renewable Energy Laboratory develop a photo-voltaic solar cell that converts 32.3 percent of the sunlight that hits it into electricity. The high conversion efficiency was achieved by combining three layers of photo-voltaic materials into a single solar cell. The cell performed most efficiently when it received sunlight concentrated to 50 times normal. To use such cells in practical applications, the cell is mounted in a device that uses lenses or mirrors to concentrate sunlight onto the cell. Such “concentrator” systems are mounted on tracking systems that keep them pointed toward the sun.
1999
The National Renewable Energy Laboratory achieves a new efficiency record for thin-film photo-voltaic solar cells. The measurement of 18.8 percent efficiency for the prototype solar cell topped the previous record by more than 1 percent.
1999
Cumulative worldwide installed photo-voltaic capacity reaches 1000 megawatts.
2000
First Solar begins production in Perrysburg, Ohio, at the world's largest photo-voltaic manufacturing plant with an estimated capacity of producing enough solar panels each year to generate 100 megawatts of power.
2000
At the International Space Station, astronauts begin installing solar panels on what will be the largest solar power array deployed in space. Each 'wing' of the array consists of 32,800 solar cells.
2000
Sandia National Laboratories develops a new inverter for solar electric systems that will increase the safety of the systems during a power outage. Inverters convert the direct current (DC) electrical output from solar systems into alternating current (AC), which is the standard current for household wiring and for the power lines that supply electricity to homes.
2000
Two new thin-film solar modules, developed by BP Solarex, break previous performance records. The company's 0.5-square-meter module achieves 10.8% conversion efficiency-the highest in the world for thin-film modules of its kind. And its 0.9-square-meter module achieved 10.6% conversion efficiency and a power output of 91.5 watts - the highest power output for any thin-film module in the world.
2001
NASA's solar-powered aircraft-Helios sets a new world record for non-rocket-powered aircraft: 96,863 feet, more than 18 miles high.
2001
The National Space Development Agency of Japan, or NASDA, announces plans to develop a satellite-based solar power system that would beam energy back to Earth. A satellite carrying large solar panels would use a laser to transmit the power to an airship at an altitude of about 12 miles, which would then transmit the power to Earth.
2001
TerraSun LLC develops a unique method of using holographic films to concentrate sunlight onto a solar cell. Concentrating solar cells typically use Fresnel lenses or mirrors to concentrate sunlight. TerraSun claims that the use of holographic optics allows more selective use of sunlight, allowing light not needed for power production to pass through the transparent modules. This capability allows the modules to be integrated into buildings as skylights.
2001
PowerLight Corporation places online in Hawaii the world's largest hybrid system that combines the power from both wind and solar energy. The grid-connected system is unusual in that its solar energy capacity-175 kilowatts- is larger than its wind energy capacity of 50 kilowatts. Such hybrid power systems combine the strengths of both energy systems to maximize the available power.
2001
British Petroleum (BP) and BP Solar announce the opening of a service station in Indianapolis that features a solar-electric canopy. The Indianapolis station is the first U.S. ' BP Connect' store, a model that BP intends to use for all new or significantly revamped BP service stations. The canopy is built using translucent photo-voltaic modules made of thin films of silicon deposited onto glass.
2002
NASA successfully conducts two tests of a solar-powered, remote-controlled aircraft called Pathfinder Plus. In the first test in July, researchers demonstrated the aircraft’s use as a high-altitude platform for telecommunications technologies. Then, in September, a test demonstrated its use as an aerial imaging system for coffee growers.
2002
Union Pacific Railroad installs 350 blue-signal rail yard lanterns, which incorporate energy-saving light-emitting diode (LED) technology with solar cells, at its North Platt, Nebraska, rail yard—the largest rail yard in the United States.
2002
ATS Automation Tooling Systems Inc. in Canada starts to commercialize an innovative method of producing solar cells, called Spheral Solar technology. The technology based on tiny silicon beads bonded between two sheets of aluminum foil promises lower costs due to its greatly reduced use of silicon relative to conventional multi-crystalline silicon solar cells. The technology is not new. It was championed by Texas Instruments (TI) in the early 1990s. But despite U.S. Department of Energy (DOE) funding, TI dropped the initiative.
All buildings will be built to combine energy-efficient design and construction practices and renewable energy technologies for a net-zero energy building. In effect, the building will conserve enough and produce its own energy supply to create a new generation of cost-effective buildings that have zero net annual need for non-renewable energy.
Photo-voltaic's research and development will continue intense interest in new materials, cell designs, and novel approaches to solar material and product development. It is a future where the clothes you wear and your mode of transportation can produce power that is clean and safe.
Technology road-maps for the future outline the research and development path to full competitiveness of concentrating solar power (CSP) with conventional power generation technologies within a decade. The potential of solar power in the Southwest United States is comparable in scale to the hydro-power resource of the Northwest. A desert area 10 miles by 15 miles could provide 20,000 megawatts of power, while the electricity needs of the entire United States could theoretically be met by a photo-voltaic array within an area 100 miles on a side. Concentrating solar power, or solar thermal electricity, could harness the sun's heat energy to provide large-scale, domestically secure, and environmentally friendly electricity.
The price of photo-voltaic power will be competitive with traditional sources of electricity within 10 years.
Solar electricity will be used to electrolyze water, producing hydrogen for fuel cells for transportation and buildings.
2002
The largest solar power facility in the Northwest—the 38.7-kilowatt White Bluffs Solar Station-goes online in Richland, Washington.
2006
Polysilicon use in photo-voltaics exceeds all other polysilicon use for the first time.
2006
New World Record Achieved in Solar Cell Technology - New Solar Cell Breaks the '40 Percent Efficient' Sunlight-to-Electricity Barrier.
2007
Google solar panel project begins operation.
2007
University of Delaware claims to achieve new world record in Solar Cell Technology without independent confirmation - 42.8% efficiency.
2008
New record achieved in solar cell efficiency. Scientists at the U.S. Department of Energy's National Renewable Energy Laboratory (NREL) have set a world record in solar cell efficiency with a photo-voltaic device that converts 40.8 percent of the light that hits it into electricity. However, it was only under the concentrated energy of 326 suns that this was achieved. The inverted metamorphic triple-junction solar cell was designed, fabricated and independently measured at NREL.
2011
Fast-growing factories in China push manufacturing costs down to about $1.25 per watt for silicon photo-voltaic modules. Installations double worldwide.
2012
3D PV-cell with 30% more energy efficiency.
2012 Record Breaking Solar Plants in World
The past few years have seen enormous investment in utility-scale solar plants, with records for the largest frequently being broken. As of 2012, the history's largest solar energy plant is the Golmud Solar Park in China, with an installed capacity of 200 megawatts. This is arguably surpassed by India's Gujarat Solar Park, a collection of solar farms scattered around the Gujarat region, boasting a combined installed capacity of 605 megawatts.
2012 Record Breaking Solar Plants in Pakistan
Pakistan has stepped ahead by inaugurating the first ever solar power on-grid power plant in Islamabad. The Project titled 'Introduction of Clean Energy by Solar Electricity Generation System' is a special grant aid project of Japan International Cooperation Agency (JICA) under Cool Earth Partnership. This project includes the installation of 178 kilowatts (kW) photo-voltaic (PV) systems each at the premises of Planning Commission and Pakistan Engineering Council, Islamabad which would cater to the needs of both, the Planning Commission (P Block), Pak Secretariat and Pakistan Engineering Council Buildings. The entire setup amounts to a total generation capacity of 356 kW.
This is the first on-grid solar PV project which has the arrangement of net-metering thereby allowing the beneficiaries to sell the surplus electricity to Islamabad Electric Supply Company (IESCO), the electricity distribution company of Islamabad Division. The Project is executed with the grant assistance worth 480 million Yen (approx. 553.63 million Pakistani Rupees)
2014
'As the largest concentrating solar power (CSP) plant in the world', Ivanpah harnesses the abundant sunlight of the Southwest United States to provide power on a massive scale. The facility has the capacity to generate 392 megawatts (MW) of clean electricity - enough to power 94,400 average American homes. Most of the power generated by the system will be sold under long-term power purchase agreements to Pacific Gas & Electric and Southern California Edison Company.
2016
University of New South Wales engineers established a new world record for unfocused sunlight conversion to electricity with an efficiency increase to 34.5%. The record was set by UNSW's Australian Centre for Advanced Photo-voltaic (ACAP) using a 28 cm2 four-junction mini-module - embedded in a prism - that extracts the maximum energy from sunlight. It does this by splitting the incoming rays into four bands, using a four-junction receiver to squeeze even more electricity from each beam of sunlight.
Today we see solar cells in a wide variety of places. You may see solar-powered cars. There is even a solar-powered aircraft that has flown higher than any other aircraft except the Blackbird. With the cost of solar cells well within everyone's budget, solar power has never looked so tempting.
New technology has given us screen-printed solar cells, and a solar fabric that can be used to side a house, even solar shingles that install on our roofs. International markets have opened up and solar panel manufacturers are now playing a key role in the solar power industry.
Overall, the market for solar panels is expected to continue to grow globally beyond 2017. As the cost of installing and making solar panels continues to drop, the technology will increasingly be more attractive to customers as an alternative to fossil fuel-based energy.
First Solar says it has converted 22.1 percent of the energy in sunlight into electricity using experimental cells made from cadmium telluride—a technology that today represents around 5 percent of the worldwide solar power market.
2018
Alta Devices, a US-based specialty gallium arsenide (GaAs) PV manufacturer, claimed to have achieved a solar cell conversion efficiency record of 29.1%, as certified by Germany's Fraunhofer ISE CalLab.
The first dedicated solar panel recycling plant in Europe and "possibly in the world" is opened in France.
2019
The world record for solar cell efficiency at 47.1% was achieved by using multi-junction concentrator solar cells, developed at National Renewable Energy Laboratory, Golden, Colorado, USA. This is above the standard rating of 37% for polycrystalline photo-voltaic or thin-film solar cells as of 2018.[42][additional citation(s) needed] It was reported in a study published in 2020.
2020
Solar cell efficiency of perovskite solar cells have increased from 3.8% in 2009 to 25.2% in 2020 in single-junction architectures, and, in silicon-based tandem cells, to 29.1%, exceeding the maximum efficiency achieved in single-junction silicon solar cells.
6 March – Scientists show that adding a layer of perovskite crystals on top of textured or planar silicon to create a tandem solar cell enhances its performance up to a power conversion efficiency of 26%. This could be a low cost way to increase efficiency of solar cells.
13 July – The first global assessment into promising approaches of solar photo-voltaic modules recycling is published. Scientists recommend "research and development to reduce recycling costs and environmental impacts compared to disposal while maximizing material recovery" as well as facilitation and use of techno–economic analyses.
3 July – Scientists show that adding an organic-based ionic solid into perovskites can result in substantial improvement in solar cell performance and stability. The study also reveals a complex degradation route that is responsible for failures in aged perovskite solar cells. The understanding could help the future development of photo-voltaic technologies with industrially relevant longevity.
2021
12 April – Scientists develop a prototype and design rules for both-sides-contacted silicon solar cells with conversion efficiencies of 26% and above, Earth's highest for this type of solar cell.
7 May – Researchers address a key problem of perovskite solar cells by increasing their stability and long-term reliability with a form of "molecular glue".
21 May – The first industrial commercial production line of perovskite solar panels, using an inkjet printing procedure, is launched.
Source [wikipedia - Update-2022]