Review of Photovoltaic Energy Technologies in Relation to the Environment and Availability of Materials

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URL of the actual page: https://en.wikipedia.org/wiki/Multi-junction_solar_cell
Title of the Page: Multi-junction solar cell
Editor, Date: Wikipedia, the free encyclopedia
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Multi-junction (MJ) solar cells are solar cells with multiple p–n junctions made of different semiconductor materials. Each material's p-n junction will produce electric current in response to different wavelengths of light. The use of multiple semiconducting materials allows the absorbance of a broader range of wavelengths, improving the cell's sunlight to electrical energy conversion efficiency.

Traditional single-junction cells have a maximum theoretical efficiency of 33.16 percent. Theoretically, an infinite number of junctions would have a limiting efficiency of 86.8 percent under highly concentrated sunlight.

Currently, the best lab examples of traditional crystalline silicon (c-Si) solar cells have efficiencies between 20 percent and 25 percent, while lab examples of multi-junction cells have demonstrated performance over 46 percent under concentrated sunlight. Commercial examples of tandem cells are widely available at 30 percent under one-sun illumination, and improve to around 40 percent under concentrated sunlight. However, this efficiency is gained at the cost of increased complexity and manufacturing price. To date, their higher price and higher price-to-performance ratio have limited their use to special roles, notably in aerospace where their high power-to-weight ratio is desirable. In terrestrial applications, these solar cells are emerging in concentrator photovoltaics (CPV), with a growing number of installations around the world.

Tandem fabrication techniques have been used to improve the performance of existing designs. In particular, the technique can be applied to lower cost thin-film solar cells using amorphous silicon, as opposed to conventional crystalline silicon, to produce a cell with about 10 percent efficiency that is lightweight and flexible. This approach has been used by several commercial vendors, but these products are currently limited to certain niche roles, like roofing materials.

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URL of the actual page: https://en.wikipedia.org/wiki/Cadmium_telluride_photovoltaics
Title of the Page: Cadmium telluride photovoltaics
Editor, Date: Wikipedia, the free encyclopedia
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Cadmium telluride (CdTe) photovoltaics describes a photovoltaic (PV) technology that is 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.

On a lifecycle basis, CdTe PV has the smallest carbon footprint, lowest water use and shortest energy payback time of any current photo voltaic technology. CdTe's energy payback time of less than a year allows for faster carbon reductions without short-term energy deficits.

The toxicity of cadmium is an environmental concern mitigated by the recycling of CdTe modules at the end of their life time, though there are still uncertainties regarding the recycling of CdTe modules and the public opinion is skeptical towards this technology. The usage of rare materials may also become a limiting factor to the industrial scalability of CdTe technology in the mid-term future. The abundance of tellurium—of which telluride is the anionic form—is comparable to that of platinum in the earth's crust and contributes significantly to the module's cost.

CdTe photovoltaics are used in some of the world's largest photovoltaic power stations, such as the Topaz Solar Farm. With a share of 5.1 percent of worldwide PV production, CdTe technology accounted for more than half of the thin film market in 2013. A prominent manufacturer of CdTe thin film technology is the company First Solar, based in Tempe, Arizona.

URL of the actual page: https://en.wikipedia.org/wiki/Solar_cell#Research_in_solar_cells
Title of the Page: Solar Cells: Research in Solar Cells
Editor, Date: Wikipedia, the free encyclopedia
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- Perovskite solar cells are solar cells that include a perovskite-structured material as the active layer.

- With a transparent rear side, bifacial solar cells can absorb light from both the front and rear sides.

- Intermediate band photovoltaics in solar cell research provides methods for exceeding the Shockley–Queisser limit on the efficiency of a cell.

- Liquid inks

- Photon upconversion is the process of using two low-energy (e.g., infrared) photons to produce one higher energy photon; downconversion is the process of using one high energy photon (e.g.,, ultraviolet) to produce two lower energy photons

- Dye-sensitized solar cells (DSSCs) are made of low-cost materials and do not need elaborate manufacturing equipment, so they can be made in a DIY fashion.

- Quantum dot solar cells (QDSCs) are based on the Gratzel cell, or dye-sensitized solar cell architecture, but employ low band gap semiconductor nanoparticles, fabricated with crystallite sizes small enough to form quantum dots

- Organic solar cells and polymer solar cells are built from thin films (typically 100 nm) of organic semiconductors including polymers, such as polyphenylene vinylene and small-molecule compounds like copper phthalocyanine (a blue or green organic pigment) and carbon fullerenes and fullerene derivatives such as PCBM.

- Adaptive cells change their absorption/reflection characteristics depending on environmental conditions.

- Surface texturing

- Encapsulation

URL of the actual page: https://en.wikipedia.org/wiki/Copper_indium_gallium_selenide_solar_cells
Title of the Page: Copper indium gallium selenide solar cells
Editor, Date: Wikipedia, the free encyclopedia
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A copper indium gallium selenide solar cell (or CIGS cell, sometimes CI(G)S or CIS 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 and selenium 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.

CIGS is one of three mainstream thin-film photovoltaic (PV) technologies, the other two being cadmium telluride and amorphous silicon. Like these materials, CIGS layers are thin enough to be flexible, allowing them to be deposited on flexible substrates. However, as all of these technologies normally use high-temperature deposition techniques, the best performance normally comes from cells deposited on glass, even though advances in low-temperature deposition of CIGS cells have erased much of this performance difference. CIGS outperforms polysilicon at the cell level, however its module efficiency is still lower, due to a less mature upscaling.

Thin-film market share is stagnated at around 15 percent, leaving the rest of the PV market to conventional solar cells made of crystalline silicon. In 2013, the market share of CIGS alone was about 2 percent and all thin-film technologies combined fell below 10 percent. CIGS cells continue being developed, as they promise to reach silicon-like efficiencies, while maintaining their low costs, as is typical for thin-film technology. Prominent manufacturers of CIGS photovoltaics were the now-bankrupt companies Nanosolar and Solyndra. Current market leader is the Japanese company Solar Frontier, with Global Solar and GSHK Solar also producing solar modules free of any heavy metals such as cadmium and/or lead. Many CIGS solar panel manufacturer companies have gone bankrupt.

URL of the actual page: https://fenix.tecnico.ulisboa.pt/downloadFile/395145007806/Resumo-A.Velozo.pdf
Title of the Page: Crystalline silicon photovoltaic solar cells using amorphous silicon as dopant source
Editor, Date: Department of Physics of IST, Lisbon, 2012
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Without doing extensive optimization work, an efficiency of 3.4 percent has been achieved.

URL of the actual page: https://www.sciencedirect.com/science/article/abs/pii/S0038092X15005241
Title of the Page: Heavily phosphorus-doped silicon nanoparticles as intermediate layer in solar cell based on IFO/p-Si heterojunction
Editor, Date: Solar Energy Volume 122, December 2015
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The goal of this work is to investigate the effect of heavily phosphorus-doped silicon nanoparticles (NP-n plus)Si introduced between the p-type silicon substrate and indium fluorine oxide (IFO) thin film on the performance of the IFO/(NP-n plus/pp plus)Cz-Si (Czochralski silicon)/indium tin oxide (ITO) heterojunction solar cell. Nanoparticles were deposited on p-Si surface from ethanol-based colloidal suspension by ultrasonic spray coating. The IFO and ITO films were grown by ultrasonic spray pyrolysis. A reference solar cell without nanoparticles with IFO/(pp plus)Cz-Si/ITO structure was also fabricated and studied. SEM, EDX, XPS, and FTIR spectroscopy, reflection and external quantum efficiency spectra, Suns–Voc measurements were used for the analysis. It was shown that the phosphorus doping level of (NP-n plus) Si is of about 3 times 1020 cm−3. After deposition, NPs are covered with SiOx layer which is removed by HF dip. The mean NPs size is of about 5.7 nm. An increase in duration of NPs deposition from 7 to 19 min leads to an increase in density of NPs from 5.6 times 1011 to 1.06 times 1012 cm−2 and, consequently, to an increase in NPs surface coverage from 10.6 percent to 27.5 percent. IFO/(NP-n plus/pp plus)Cz-Si solar cell with NPs surface coverage of 27.5 percent have shown noticeably higher power conversion efficiency of 13.2 percent in comparison with 11.9 percent efficiency obtained for the reference cell. This result is achieved due to increased open-circuit voltage (571 mV in the NPs-based solar cell against 484 mV for the reference cell).

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URL of the actual page: https://www.sciencedirect.com/science/article/abs/pii/S0927024809001354
Title of the Page: Phosphorus-doped silicon quantum dots for all-silicon quantum dot tandem solar cells
Editor, Date: Solar Energy Materials and Solar Cells Volume 93, Issue 9, September 2009
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Doping of Si quantum dots is important in the field of Si quantum dots-based solar cells. Structural, optical and electrical properties of Si QDs formed as multilayers in a SiO2 matrix with various phosphorus (P) concentrations introduced during the sputtering process were investigated for its potential application in all-silicon quantum dot tandem solar cells. The formation of Si quantum dots was confirmed by transmission electron microscopy. The addition of phosphorus was observed to modify Si crystallization, though the phosphorus concentration was found to have little effect on quantum dot size. Secondary ion mass spectroscopy results indicate minimal phosphorus diffusion from Si QDs layers to adjacent SiO2 layers during high-temperature annealing. Resistivity is significantly decreased by phosphorus doping. Resistivity of slightly phosphorus-doped (0.1 at percent P) films is seven orders of magnitude lower than that of intrinsic films. Dark resistivity and activation energy measurements indicate the existence of an optimal phosphorus concentration. The photoluminescence intensity increases with the phosphorus concentration, indicating a tendency towards radiative recombination in the doped films. These results can provide optimal condition for future Si quantum dots-based solar cells.

URL of the actual page: https://en.wikipedia.org/wiki/Boron#Biological_role
Title of the Page: Boron: Biological Role
Editor, Date: Wikipedia, the free encyclopedia
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Boron is an essential plant nutrient, required primarily for maintaining the integrity of cell walls. However, high soil concentrations of greater than 1.0 ppm lead to marginal and tip necrosis in leaves as well as poor overall growth performance. Levels as low as 0.8 ppm produce these same symptoms in plants that are particularly sensitive to boron in the soil. Nearly all plants, even those somewhat tolerant of soil boron, will show at least some symptoms of boron toxicity when soil boron content is greater than 1.8 ppm. When this content exceeds 2.0 ppm, few plants will perform well and some may not survive.

It is thought that boron plays several essential roles in animals, including humans, but the exact physiological role is poorly understood. A small human trial published in 1987 reported on postmenopausal women first made boron deficient and then repleted with 3 mg/day. Boron supplementation markedly reduced urinary calcium excretion and elevated the serum concentrations of 17 beta-estradiol and testosterone.

The U.S. Institute of Medicine has not confirmed that boron is an essential nutrient for humans, so neither a Recommended Dietary Allowance (RDA) nor an Adequate Intake have been established. Adult dietary intake is estimated at 0.9 to 1.4 mg/day, with about 90 percent absorbed. What is absorbed is mostly excreted in urine. The Tolerable Upper Intake Level for adults is 20 mg/day.

In 2013, a hypothesis suggested it was possible that boron and molybdenum catalyzed the production of RNA on Mars with life being transported to Earth via a meteorite around 3 billion years ago.

There exist several known boron-containing natural antibiotics. The first one found was boromycin, isolated from streptomyces.

Congenital endothelial dystrophy type 2, a rare form of corneal dystrophy, is linked to mutations in SLC4A11 gene that encodes a transporter reportedly regulating the intracellular concentration of boron

URL of the actual page: https://en.wikipedia.org/wiki/Boron
Title of the Page: Boron
Editor, Date: Wikipedia, the free encyclopedia
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Boron is a chemical element with the symbol B and atomic number 5. Produced entirely by cosmic ray spallation and supernovae and not by stellar nucleosynthesis, it is a low-abundance element in the Solar System and in the Earth's crust. It constitutes about 0.001 percent by weight of Earth's crust. Boron is concentrated on Earth by the water-solubility of its more common naturally occurring compounds, the borate minerals. These are mined industrially as evaporites, such as borax and kernite. The largest known boron deposits are in Turkey, the largest producer of boron minerals. 

URL of the actual page: https://en.wikipedia.org/wiki/Tellurium#Biological_role
Title of the Page: Tellurium: Biological Role
Editor, Date: Wikipedia, the free encyclopedia
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Tellurium has no known biological function, although fungi can incorporate it in place of sulfur and selenium into amino acids such as telluro-cysteine and telluro-methionine. Organisms have shown a highly variable tolerance to tellurium compounds. Many bacteria, such as Pseudomonas aeruginosa, take up tellurite and reduce it to elemental tellurium, which accumulates and causes a characteristic and often dramatic darkening of cells. In yeast, this reduction is mediated by the sulfate assimilation pathway. Tellurium accumulation seems to account for a major part of the toxicity effects. Many organisms also metabolize tellurium partly to form dimethyl telluride, although dimethyl ditelluride is also formed by some species. Dimethyl telluride has been observed in hot springs at very low concentrations.

Tellurite agar is used to identify members of the corynebacterium genus, most typically Corynebacterium diphtheriae, the pathogen responsible for diphtheria.

URL of the actual page: https://en.wikipedia.org/wiki/Tellurium
Title of the Page: Tellurium
Editor, Date: Wikipedia, the free encyclopedia
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Tellurium is a chemical element with the symbol Te and atomic number 52. It is a brittle, mildly toxic, rare, silver-white metalloid. Tellurium is chemically related to selenium and sulfur, all three of which are chalcogens. It is occasionally found in native form as elemental crystals. Tellurium is far more common in the Universe as a whole than on Earth. Its extreme rarity in the Earth's crust, comparable to that of platinum, is due partly to its formation of a volatile hydride that caused tellurium to be lost to space as a gas during the hot nebular formation of Earth, and partly to tellurium's low affinity for oxygen, which causes it to bind preferentially to other chalcophiles in dense minerals that sink into the core.

Tellurium-bearing compounds were first discovered in 1782 in a gold mine in Kleinschlatten, Transylvania (now Zlatna, Romania) by Austrian mineralogist Franz-Joseph Müller von Reichenstein, although it was Martin Heinrich Klaproth who named the new element in 1798 after the Latin word for "earth", tellus. Gold telluride minerals are the most notable natural gold compounds. However, they are not a commercially significant source of tellurium itself, which is normally extracted as a by-product of copper and lead production.

Commercially, the primary use of tellurium is copper (tellurium copper) and steel alloys, where it improves machinability. Applications in CdTe solar panels and cadmium telluride semiconductors also consume a considerable portion of tellurium production. Tellurium is considered a technology-critical element.

Tellurium has no biological function, although fungi can use it in place of sulfur and selenium in amino acids such as tellurocysteine and telluromethionine. In humans, tellurium is partly metabolized into dimethyl telluride, (CH3)2Te, a gas with a garlic-like odor exhaled in the breath of victims of tellurium exposure or poisoning.

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URL of the actual page: https://en.wikipedia.org/wiki/Boron#Applications
Title of the Page: Boron: Applications
Editor, Date: Wikipedia, the free encyclopedia
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Nearly all boron ore extracted from the Earth is destined for refinement into boric acid and sodium tetraborate pentahydrate. In the United States, 70 paercent of the boron is used for the production of glass and ceramics. The major global industrial-scale use of boron compounds (about 46 percent of end-use) is in production of glass fiber for boron-containing insulating and structural fiberglasses, especially in Asia. Boron is added to the glass as borax pentahydrate or boron oxide, to influence the strength or fluxing qualities of the glass fibers. Another 10 percent of global boron production is for borosilicate glass as used in high strength glassware. About 15 percent of global boron is used in boron ceramics, including super-hard materials discussed below. Agriculture consumes 11 percent of global boron production, and bleaches and detergents about 6 paercent.

URL of the actual page: https://en.wikipedia.org/wiki/Boron#Production
Title of the Page: Boron: Production
Editor, Date: Wikipedia, the free encyclopedia
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Economically important sources of boron are the minerals colemanite, rasorite (kernite), ulexite and tincal. Together these constitute 90 percent of mined boron-containing ore. The largest global borax deposits known, many still untapped, are in Central and Western Turkey, including the provinces of Eskisehir, Kütahya and Balıkesir. Global proven boron mineral mining reserves exceed one billion metric tonnes, against a yearly production of about four million tonnes.

Turkey and the United States are the largest producers of boron products. Turkey produces about half of the global yearly demand, through Eti Mine Works (Turkish: Eti Maden Isletmeleri) a Turkish state-owned mining and chemicals company focusing on boron products. It holds a government monopoly on the mining of borate minerals in Turkey, which possesses 72 percent of the world's known deposits. In 2012, it held a 47 percent share of production of global borate minerals, ahead of its main competitor, Rio Tinto Group.

Almost a quarter (23 percent) of global boron production comes from the single Rio Tinto Borax Mine (also known as the U.S. Borax Boron Mine)

URL of the actual page: https://en.wikipedia.org/wiki/Tellurium#Occurrence
Title of the Page: Tellurium: Occurrence
Editor, Date: Wikipedia, the free encyclopedia
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With an abundance in the Earth's crust comparable to that of platinum (about 1 micro micrograms/kg), tellurium is one of the rarest stable solid elements. In comparison, even the rarest of the stable lanthanides have crustal abundances of 500 micrograms/kg (see Abundance of the chemical elements).

This rarity of tellurium in the Earth's crust is not a reflection of its cosmic abundance. Tellurium is more abundant than rubidium in the cosmos, though rubidium is 10,000 times more abundant in the Earth's crust. The rarity of tellurium on Earth is thought to be caused by conditions during preaccretional sorting in the solar nebula, when the stable form of certain elements, in the absence of oxygen and water, was controlled by the reductive power of free hydrogen. Under this scenario, certain elements that form volatile hydrides, such as tellurium, were severely depleted through evaporation of these hydrides. Tellurium and selenium are the heavy elements most depleted by this process

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URL of the actual page: https://www.power-technology.com/features/the-worlds-biggest-solar-power-plants/
Title of the Page: The world’s biggest solar power plants
Editor, Date: Power Technology, 10 Jan 2020
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Solar is one of the fastest growing energy sources in the world, and with countries racing to assert their dominance in the burgeoning industry the leading nation is never clear for long. Power-technology.com profiles the eight biggest solar power plants in the world.

Solar is one of the fastest-growing renewable energy sources in the world and, with countries racing to assert their dominance in the burgeoning industry, the leading nation is never clear for long.

The nations pulling ahead in the sunny sector are China and the US, which together account for two-thirds of the global growth in solar power.

Solar energy capacity has increased by approximately 60 percent over the last five years, rising to 485.82GW in 2018. But where are the biggest solar power plants? Power Technology profiles the biggest operational solar power plants in the world, based on installed capacity.

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URL of the actual page: https://www.npr.org/sections/thetwo-way/2016/02/04/465568055/morocco-unveils-a-massive-solar-power-plant-in-the-sahara?t=1569147243029&t=1620747385819
Title of the Page: Morocco Unveils A Massive Solar Power Plant In The Sahara
Editor, Date: NPR, The Two-Way, February 4, 2016
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Morocco has officially turned on a massive solar power plant in the Sahara Desert, kicking off the first phase of a planned project to provide renewable energy to more than a million Moroccans.

From The Archives

2014
World's Largest Solar Plant Opens In California

2013
Under Construction: The World's Largest Thermal Solar Plant
The Noor I power plant is located near the town of Ouarzazate, on the edge of the Sahara. It's capable of generating up to 160 megawatts of power and covers thousands of acres of desert, making the first stage alone one of the world's biggest solar thermal power plants.

When the next two phases, Noor II and Noor III, are finished, the plant will be the single largest solar power production facility in the world, The Guardian says.

Morocco currently relies on imported sources for 97 percent of its energy consumption, according to the World Bank, which helped fund the Noor power plant project. Investing in renewable energy will make Morocco less reliant on those imports as well as reduce the nation's long-term carbon emissions by millions of tons.

URL of the actual page: https://www.cnbc.com/2019/08/01/chinas-didi-to-form-jv-with-bp-to-build-electric-vehicle-charging.html
Title of the Page: China’s Didi partners up with BP to build an electric vehicle-charging network
Editor, Date: CNBC, AUG 1 2019
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- Didi says it will form a joint venture with BP aimed at providing charging services to Didi and non-Didi car owners.

- The aim is to scale up the charging network “significantly” in China after the joint venture with BP is established.

- China is the world’s largest market for electric cars, and is home to numerous start-ups looking to challenge Tesla.

Didi Chuxing, the Chinese ride-hailing giant, has teamed up with BP to build electric vehicle-charging stations in China.

The company announced Thursday that it would form a joint venture with the British oil major aimed at providing charging services to both Didi and non-Didi car owners.

BP has already linked its first charging site in the Chinese port city of Guangzhou with Didi’s open automobile solutions platform, Didi said in a statement. The Chinese firm pumped 1 billion Dollar into its auto services business, called XAS, last year.

URL of the actual page: https://www.cnbc.com/2019/08/01/tesla-plans-solar-roof-testing-at-fremont-car-plant-permits-reveal.html
Title of the Page: Tesla is planning to do solar roof testing at its Fremont car plant, building permits reveal
Editor, Date: CNBC, AUG 1 2019
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- Building permits reveal Tesla plans to do solar roof testing at its car plant in Fremont, California.

- Tesla has slashed and struggled with its solar business after acquiring SolarCity for 2.6 billion Dollar in 2016.

- CEO Elon Musk recently tweeted that he is hoping the company will be able to produce about 1,000 solar rooftops a week by the end of this year.

Tesla is planning to build “a test structure to evaluate Tesla solar roof product and installation process” at the site of its car plant in Fremont, California, according to a building permit issued to the company in July.

The move suggests that one of Tesla’s long-delayed products is inching forward, as Elon Musk hinted in recent tweets, but it still needs improvements.

URL of the actual page: https://www.cnbc.com/2019/07/19/pay-as-you-go-energy-could-help-with-access-to-electricity-in-africa.html
Title of the Page: How pay-as-you go energy systems could help with access to electricity in Africa
Editor, Date: CNBC, JUL 19 2019
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- For people living in the developed world, electricity is something that can perhaps be taken for granted.

- Some businesses want to broaden access to electricity in sub-Saharan Africa through pay-as-you-go schemes.


For people living in the developed world, electricity is something that can perhaps be taken for granted — with the flick of a switch or the press of a button they have lighting, TV and a huge number of other modern conveniences.

Yet many people do not enjoy the same benefits. In sub-Saharan Africa, for example, 600 million people lack access to electricity, according to the International Energy Agency.

In order to broaden access and provide “universal electricity for all,” the IEA says that “decentralized systems, led by solar PV (photovoltaic) in off-grid and mini-grid systems, will be the least-cost solution for three-quarters of the additional connections needed.”

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URL of the actual page: https://www.cnbc.com/2019/07/15/morgan-stanley-amazon-project-kuiper-could-be-a-100-billion-business.html
Title of the Page: This new business from Amazon represents a ‘100 billion Dollar opportunity,’ Morgan Stanley says
Editor, Date: CNBC, JUL 15 2019
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- Amazon plans to launch Project Kuiper, a network of 3,236 small satellites to create an interconnected network that beams high-speed internet to anywhere on Earth.

- Morgan Stanley estimates Project Kuiper represents as much as a "100 billion Dollar opportunity."

- The firm’s estimate is based on its expectation that the space economy will grow to more than 1 trillion Dollar over the next 20 years.


Amazon is looking to expand its empire and Morgan Stanley believes Jeff Bezos’ ambitious satellite internet plan may become one of its most lucrative businesses.

Called Project Kuiper, Amazon aims to launch a network of 3,236 small satellites to create an interconnected network that beams high-speed internet to anywhere on Earth. While Amazon has yet to outline a timeline or cost for Project Kuiper, in a note on Monday to investors, Morgan Stanley analyst Adam Jonas highlighted the network’s potential.

URL of the actual page: https://www.cnbc.com/2019/08/02/amazon-announces-new-renewable-energy-projects-in-the-us-and-ireland.html
Title of the Page: Amazon announces new renewable energy projects in the US and Ireland
Editor, Date: CNBC, AUG 2 2019
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- The projects are in Cork, Ireland and Pittsylvania County, Virginia.

- It’s expected that they will start producing energy in 2020, according to Amazon. 


Tech giant Amazon is to invest in two new renewable energy projects in the U.S. and Ireland. In an announcement Thursday, the firm said the projects – in Pittsylvania County, Virginia and Cork, Ireland – were expected to commence production in 2020.

The project in Ireland will be a wind farm with 23.2 megawatts (MW) of capacity and is set to generate 68,000 megawatt hours (MWh) of energy per year. The facility in Virginia, a solar farm, will have 45 MW of capacity and produce an expected 100,000 MWh of energy each year.

URL of the actual page: https://en.wikipedia.org/wiki/Indium
Title of the Page: Indium
Editor, Date: Wikipedia, the free encyclopedia
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Indium is a chemical element with the symbol In and atomic number 49. Indium is the softest metal that is not an alkali metal. It is a silvery-white metal that resembles tin in appearance. It is a post-transition metal that makes up 0.21 parts per million of the Earth's crust. Indium has a melting point higher than sodium and gallium, but lower than lithium and tin. Chemically, indium is similar to gallium and thallium, and it is largely intermediate between the two in terms of its properties. Indium was discovered in 1863 by Ferdinand Reich and Hieronymous Theodor Richter by spectroscopic methods. They named it for the indigo blue line in its spectrum. Indium was isolated the next year.

Indium is a minor component in zinc sulfide ores and is produced as a byproduct of zinc refinement. It is most notably used in the semiconductor industry, in low-melting-point metal alloys such as solders, in soft-metal high-vacuum seals, and in the production of transparent conductive coatings of indium tin oxide (ITO) on glass. Indium is considered a technology-critical element.

Indium has no biological role. Its compounds are toxic when injected into the bloodstream. Most occupational exposure is through ingestion, from which indium compounds are not absorbed well, and inhalation, from which they are moderately absorbed.

URL of the actual page: https://en.wikipedia.org/wiki/Indium#Applications
Title of the Page: Indium: Applications
Editor, Date: Wikipedia, the free encyclopedia
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In 1924, indium was found to have a valued property of stabilizing non-ferrous metals, and that became the first significant use for the element. The first large-scale application for indium was coating bearings in high-performance aircraft engines during World War II, to protect against damage and corrosion; this is no longer a major use of the element. New uses were found in fusible alloys, solders, and electronics. In the 1950s, tiny beads of indium were used for the emitters and collectors of PNP alloy-junction transistors. In the middle and late 1980s, the development of indium phosphide semiconductors and indium tin oxide thin films for liquid-crystal displays (LCD) aroused much interest. By 1992, the thin-film application had become the largest end use.

Indium(III) oxide and indium tin oxide (ITO) are used as a transparent conductive coating on glass substrates in electroluminescent panels. Indium tin oxide is used as a light filter in low-pressure sodium-vapor lamps. The infrared radiation is reflected back into the lamp, which increases the temperature within the tube and improves the performance of the lamp.

Indium has many semiconductor-related applications. Some indium compounds, such as indium antimonide and indium phosphide, are semiconductors with useful properties: one precursor is usually trimethylindium (TMI), which is also used as the semiconductor dopant in II–VI compound semiconductors. InAs and InSb are used for low-temperature transistors and InP for high-temperature transistors. The compound semiconductors InGaN and InGaP are used in light-emitting diodes (LEDs) and laser diodes. Indium is used in photovoltaics as the semiconductor copper indium gallium selenide (CIGS), also called CIGS solar cells, a type of second-generation thin-film solar cell. Indium is used in PNP bipolar junction transistors with germanium: when soldered at low temperature, indium does not stress the germanium

URL of the actual page: https://en.wikipedia.org/wiki/Indium#Biological_role_and_precautions
Title of the Page: Indium: Biological role and precautions
Editor, Date: Wikipedia, the free encyclopedia
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Indium has no metabolic role in any organism. In a similar way to aluminium salts, indium(III) ions can be toxic to the kidney when given by injection. Indium tin oxide and indium phosphide harm the pulmonary and immune systems, predominantly through ionic indium, though hydrated indium oxide is more than forty times as toxic when injected, measured by the quantity of indium introduced. Radioactive indium-111 (in very small amounts on a chemical basis) is used in nuclear medicine tests, as a radiotracer to follow the movement of labeled proteins and white blood cells in the body. Indium compounds are mostly not absorbed upon ingestion and are only moderately absorbed on inhalation; they tend to be stored temporarily in the muscles, skin, and bones before being excreted, and the biological half-life of indium is about two weeks in humans.

People can be exposed to indium in the workplace by inhalation, ingestion, skin contact, and eye contact. Indium lung is a lung disease characterized by pulmonary alveolar proteinosis and pulmonary fibrosis, first described by Japanese researchers in 2003. As of 2010, 10 cases had been described, though more than 100 indium workers had documented respiratory abnormalities. The National Institute for Occupational Safety and Health has set a recommended exposure limit (REL) of 0.1 mg/m3 over an eight-hour workday.

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URL of the actual page: https://en.wikipedia.org/wiki/Cadmium#Environment
Title of the Page: Cadmium: Environment
Editor, Date: Wikipedia, the free encyclopedia
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Individuals and organizations have been reviewing cadmium's bioinorganic aspects for its toxicity. The most dangerous form of occupational exposure to cadmium is inhalation of fine dust and fumes, or ingestion of highly soluble cadmium compounds. Inhalation of cadmium fumes can result initially in metal fume fever, but may progress to chemical pneumonitis, pulmonary edema, and death.

Cadmium is also an environmental hazard. Human exposure is primarily from fossil fuel combustion, phosphate fertilizers, natural sources, iron and steel production, cement production and related activities, nonferrous metals production, and municipal solid waste incineration. Bread, root crops, and vegetables also contribute to the cadmium in modern populations.

Jinzu River area, which was contaminated with cadmium
There have been a few instances of general population poisoning as the result of long-term exposure to cadmium in contaminated food and water. Research into an estrogen mimicry that may induce breast cancer is ongoing. In the decades leading up to World War II, mining operations contaminated the Jinzu River in Japan with cadmium and traces of other toxic metals. As a consequence, cadmium accumulated in the rice crops along the riverbanks downstream of the mines. Some members of the local agricultural communities consumed the contaminated rice and developed itai-itai disease and renal abnormalities, including proteinuria and glucosuria. The victims of this poisoning were almost exclusively post-menopausal women with low iron and low body stores of other minerals. Similar general population cadmium exposures in other parts of the world have not resulted in the same health problems because the populations maintained sufficient iron and other mineral levels. Thus, although cadmium is a major factor in the itai-itai disease in Japan, most researchers have concluded that it was one of several factors.

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URL of the actual page: https://en.wikipedia.org/wiki/Indium_gallium_phosphide
Title of the Page: Indium gallium phosphide
Editor, Date: Wikipedia, the free encyclopedia
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Indium gallium phosphide (InGaP), also called gallium indium phosphide (GaInP), is a semiconductor composed of indium, gallium and phosphorus. It is used in high-power and high-frequency electronics because of its superior electron velocity with respect to the more common semiconductors silicon and gallium arsenide.

It is used mainly in HEMT and HBT structures, but also for the fabrication of high efficiency solar cells used for space applications and, in combination with aluminium (AlGaInP alloy) to make high brightness LEDs with orange-red, orange, yellow, and green colors. Some semiconductor devices such as EFluor Nanocrystal use InGaP as their core particle.

Indium gallium phosphide is a solid solution of indium phosphide and gallium phosphide.

Ga0.5In0.5P is a solid solution of special importance, which is almost lattice matched to GaAs. This allows, in combination with (AlxGa1−x)0.5In0.5, the growth of lattice matched quantum wells for red emitting semiconductor lasers, e.g. red emitting (650nm) RCLEDs or VCSELs for PMMA plastic optical fibers.

Ga0.5In0.5P is used as the high energy junction on double and triple junction photovoltaic cells grown on GaAs. Recent years have shown GaInP/GaAs tandem solar cells with AM0 (sunlight incidence in space is 1.35 kW/m2) efficiencies in excess of 25 percent.

A different composition of GaInP, lattice matched to the underlying GaInAs, is utilized as the high energy junction GaInP/GaInAs/Ge triple junction photovoltaic cells.

Growth of GaInP by epitaxy can be complicated by the tendency of GaInP to grow as an ordered material, rather than a truly random solid solution (i.e., a mixture). This changes the bandgap and the electronic and optical properties of the material.

URL of the actual page: https://en.wikipedia.org/wiki/Cadmium#Applications
Title of the Page: Cadmium: Applications
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Cadmium is a common component of electric batteries, pigments, coatings, and electroplating.

- Batteries
- Electroplating
- Nuclear fission
- Televisions
- Anticancer drugs
- Compounds
- Semiconductors
- Laboratory uses

URL of the actual page: https://en.wikipedia.org/wiki/Indium#Production_and_availability
Title of the Page: Indium: Production and availability
Editor, Date: Wikipedia, the free encyclopedia
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Indium is produced exclusively as a by-product during the processing of the ores of other metals. Its main source material are sulfidic zinc ores, where it is mostly hosted by sphalerite. Minor amounts are probably also extracted from sulfidic copper ores. During the roast-leach-electrowinning process of zinc smelting, indium accumulates in the iron-rich residues. From these, it can be extracted in different ways. It may also be recovered directly from the process solutions. Further purification is done by electrolysis. The exact process varies with the mode of operation of the smelter.

Its by-product status means that indium production is constrained by the amount of sulfidic zinc (and copper) ores extracted each year. Therefore, its availability needs to be discussed in terms of supply potential. The supply potential of a by-product is defined as that amount which is economically extractable from its host materials per year under current market conditions (i.e. technology and price). Reserves and resources are not relevant for by-products, since they cannot be extracted independently from the main-products. Recent estimates put the supply potential of indium at a minimum of 1,300 t/yr from sulfidic zinc ores and 20 t/yr from sulfidic copper ores. These figures are significantly greater than current production (655 t in 2016). Thus, major future increases in the by-product production of indium will be possible without significant increases in production costs or price.

China is a leading producer of indium (290 tonnes in 2016), followed by South Korea (195 t), Japan (70 t) and Canada (65 t). The Teck Resources refinery in Trail, British Columbia, is a large single-source indium producer, with an output of 32.5 tonnes in 2005, 41.8 tonnes in 2004 and 36.1 tonnes in 2003.

The primary consumption of indium worldwide is LCD production.

URL of the actual page: https://en.wikipedia.org/wiki/Cadmium#Occurrence
Title of the Page: Cadmium: Occurrence
Editor, Date: Wikipedia, the free encyclopedia
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Cadmium makes up about 0.1 ppm of Earth's crust. It is much rarer than zinc, which makes up about 65 ppm. No significant deposits of cadmium-containing ores are known. The only cadmium mineral of importance, greenockite (CdS), is nearly always associated with sphalerite (ZnS). This association is caused by geochemical similarity between zinc and cadmium, with no geological process likely to separate them. Thus, cadmium is produced mainly as a byproduct of mining, smelting, and refining sulfidic ores of zinc, and, to a lesser degree, lead and copper. Small amounts of cadmium, about 10 percent of consumption, are produced from secondary sources, mainly from dust generated by recycling iron and steel scrap. Production in the United States began in 1907, but wide use began after World War I.

Metallic cadmium can be found in the Vilyuy River basin in Siberia.

Rocks mined for phosphate fertilizers contain varying amounts of cadmium, resulting in a cadmium concentration of as much as 300 mg/kg in the fertilizers and a high cadmium content in agricultural soils. Coal can contain significant amounts of cadmium, which ends up mostly in flue dust. Cadmium in soil can be absorbed by crops such as rice. Chinese ministry of agriculture measured in 2002 that 28 percent of rice it sampled had excess lead and 10 percent had excess cadmium above limits defined by law. Some plants such as willow trees and poplars have been found to clean both lead and cadmium from soil.

Typical background concentrations of cadmium do not exceed 5 ng/m3 in the atmosphere; 2 mg/kg in soil; 1 micrograms/L in freshwater and 50 ng/L in seawater. Concentrations of cadmium above 10 micrograms/l may be stable in water having low total solute concentrations and pH and can be difficult to remove by conventional water treatment processes

URL of the actual page: https://en.wikipedia.org/wiki/Crystalline_silicon#Cell_technologies
Title of the Page: Crystalline Silicon: Cell Technologies
Editor, Date: Wikipedia, the free encyclopedia
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- PERC solar cell:

Passivated emitter rear contact (PERC) solar cells consist of the addition of an extra layer to the rear-side of a solar cell. This dielectric passive layer acts to reflect unabsorbed light back to the solar cell for a second absorption attempt increasing the solar cell efficiency.

A PERC is created through an additional film deposition and etching process. Etching can be done either by chemical or laser processing.

- HIT solar cell:

A HIT solar cell is composed of a mono thin crystalline silicon wafer surrounded by ultra-thin amorphous silicon layers. The acronym HIT stands for "heterojunction with intrinsic thin layer". HIT cells are produced by the Japanese multinational electronics corporation Panasonic (see also Sanyo Solar cells and plants). Panasonic and several other groups have reported several advantages of the HIT design over its traditional c-Si counterpart:

1. An intrinsic a-Si layer can act as an effective surface passivation layer for c-Si wafer.

2. The p plus/n plus doped a-Si functions as an effective emitter/BSF for the cell.

3. The a-Si layers are deposited at much lower temperature, compared to the processing temperatures for traditional diffused c-Si technology.

4. The HIT cell has a lower temperature coefficient compared to c-Si cell technology.

Owing to all these advantages, this new hetero-junction solar cell is a considered to be a promising low cost alternative to traditional c-Si based solar cells.

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URL of the actual page: https://en.wikipedia.org/wiki/Abundance_of_elements_in_Earth%27s_crust
Title of the Page: Abundance of elements in Earth's crust
Editor, Date: Wikipedia, the free encyclopedia
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The abundance of elements in Earth's crust is shown in tabulated form with the estimated crustal abundance for each chemical element shown as mg/kg, or parts per million (ppm) by mass (10,000 ppm is 1 percent).

Estimates of elemental abundance are difficult because (a) the composition of the upper and lower crust are quite different, and (b) the composition of the continental crust can vary drastically by locality.

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URL of the actual page: http://hyperphysics.phy-astr.gsu.edu/hbase/Solids/dope.html
Title of the Page: The Doping of Semiconductors
Editor, Date: http://hyperphysics.phy-astr.gsu.edu/
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The addition of a small percentage of foreign atoms in the regular crystal lattice of silicon or germanium produces dramatic changes in their electrical properties, producing n-type and p-type semiconductors.

Pentavalent impurities

Impurity atoms with 5 valence electrons produce n-type semiconductors by contributing extra electrons.

- P-Type and N-Type Semiconductors

- Bands for Doped Semiconductors

URL of the actual page: https://en.wikipedia.org/wiki/Extrinsic_semiconductor#P-type_semiconductors
Title of the Page: Extrinsic Semiconductor: P-type Semiconductors
Editor, Date: Wikipedia, the free encyclopedia
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P-type semiconductors are created by doping an intrinsic semiconductor with an electron acceptor element during manufacture. The term p-type refers to the positive charge of a hole. As opposed to n-type semiconductors, p-type semiconductors have a larger hole concentration than electron concentration. In p-type semiconductors, holes are the majority carriers and electrons are the minority carriers. A common p-type dopant for silicon is boron or gallium. For p-type semiconductors the Fermi level is below the intrinsic semiconductor and lies closer to the valence band than the conduction band.

Examples: boron, aluminium, gallium, etc.

URL of the actual page: https://en.wikipedia.org/wiki/Monocrystalline_silicon
Title of the Page: Monocrystalline silicon
Editor, Date: Wikipedia, the free encyclopedia
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Monocrystalline silicon, more often called single-crystal silicon, in short mono c-Si or mono-Si, is the base material for silicon-based discrete components and integrated circuits used in virtually all modern electronic equipment. Mono-Si also serves as a photovoltaic, light-absorbing material in the manufacture of solar cells.

It consists of silicon in which the crystal lattice of the entire solid is continuous, unbroken to its edges, and free of any grain boundaries. Mono-Si can be prepared as an intrinsic semiconductor that consists only of exceedingly pure silicon, or it can be doped by the addition of other elements such as boron or phosphorus to make p-type or n-type silicon. Due to its semiconducting properties, single-crystal silicon is perhaps the most important technological material of the last few decades—the "silicon era", because its availability at an affordable cost has been essential for the development of the electronic devices on which the present-day electronics and IT revolution is based.

Monocrystalline silicon differs from other allotropic forms, such as non-crystalline amorphous silicon—used in thin-film solar cells—and polycrystalline silicon, which consists of small crystals known as crystallites.

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URL of the actual page: https://en.wikipedia.org/wiki/Phosphorus
Title of the Page: Phosphorus
Editor, Date: Wikipedia, the free encyclopedia
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Phosphorus is a chemical element with the symbol P and atomic number 15. Elemental phosphorus exists in two major forms, white phosphorus and red phosphorus, but because it is highly reactive, phosphorus is never found as a free element on Earth. It has a concentration in the Earth's crust of about one gram per kilogram (compare copper at about 0.06 grams). In minerals, phosphorus generally occurs as phosphate.

Elemental phosphorus was first isolated as white phosphorus in 1669. White phosphorus emits a faint glow when exposed to oxygen -- hence the name, taken from Greek mythology, meaning "light-bearer" (Latin Lucifer), referring to the "Morning Star", the planet Venus. The term "phosphorescence", meaning glow after illumination, derives from this property of phosphorus, although the word has since been used for a different physical process that produces a glow. The glow of phosphorus is caused by oxidation of the white (but not red) phosphorus -- a process now called chemiluminescence. Together with nitrogen, arsenic, antimony, and bismuth, phosphorus is classified as a pnictogen.

Phosphorus is an element essential to sustaining life largely through phosphates, compounds containing the phosphate ion, PO43-. Phosphates are a component of DNA, RNA, ATP, and phospholipids, complex compounds fundamental to cells. Elemental phosphorus was first isolated from human urine, and bone ash was an important early phosphate source. Phosphate mines contain fossils because phosphate is present in the fossilized deposits of animal remains and excreta.

URL of the actual page: https://en.wikipedia.org/wiki/Boron
Title of the Page: Boron
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Boron is a chemical element with the symbol B and atomic number 5. Produced entirely by cosmic ray spallation and supernovae and not by stellar nucleosynthesis, it is a low-abundance element in the Solar System and in the Earth's crust. It constitutes about 0.001 percent by weight of Earth's crust. Boron is concentrated on Earth by the water-solubility of its more common naturally occurring compounds, the borate minerals. These are mined industrially as evaporites, such as borax and kernite. The largest known boron deposits are in Turkey, the largest producer of boron minerals.

Elemental boron is a metalloid that is found in small amounts in meteoroids but chemically uncombined boron is not otherwise found naturally on Earth. Industrially, very pure boron is produced with difficulty because of refractory contamination by carbon or other elements. Several allotropes of boron exist: amorphous boron is a brown powder; crystalline boron is silvery to black, extremely hard (about 9.5 on the Mohs scale), and a poor electrical conductor at room temperature. The primary use of elemental boron is as boron filaments with applications similar to carbon fibers in some high-strength materials.

Boron is primarily used in chemical compounds. About half of all boron consumed globally is an additive in fiberglass for insulation and structural materials. The next leading use is in polymers and ceramics in high-strength, lightweight structural and refractory materials. Borosilicate glass is desired for its greater strength and thermal shock resistance than ordinary soda lime glass. Boron as sodium perborate is used as a bleach. A small amount of boron is used as a dopant in semiconductors, and reagent intermediates in the synthesis of organic fine chemicals.

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URL of the actual page: https://www.halbleiter.org/en/fundamentals/doping/
Title of the Page: Fundamentals: Doping: n- and p-semiconductors
Editor, Date: halbleiter.org, Semiconductor Technology from A to Z
Description of the Page :

Doping
Doping means the introduction of impurities into a semiconductor crystal to the defined modification of conductivity. Two of the most important materials silicon can be doped with, are boron (3 valence electrons is 3-valent) and phosphorus (5 valence electrons is 5-valent). Other materials are aluminum, indium (3-valent) and arsenic, antimony (5-valent).

The dopant is integrated into the lattice structure of the semiconductor crystal, the number of outer electrons define the type of doping. Elements with 3 valence electrons are used for p-type doping, 5-valued elements for n-doping. The conductivity of a deliberately contaminated silicon crystal can be increased by a factor of 106.

- n-doping
- p-doping
- Electronic band structure in doped semiconductors

URL of the actual page: https://en.wikipedia.org/wiki/Gallium#Production_and_availability
Title of the Page: Gallium: Production and availability
Editor, Date: Wikipedia, the free encyclopedia
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Gallium is produced exclusively as a by-product during the processing of the ores of other metals. Its main source material is bauxite, the chief ore of aluminium, but minor amounts are also extracted from sulfidic zinc ores (sphalerite being the main host mineral). In the past, certain coals were an important source.

During the processing of bauxite to alumina in the Bayer process, gallium accumulates in the sodium hydroxide liquor. From this it can be extracted by a variety of methods. The most recent is the use of ion-exchange resin. Achievable extraction efficiencies critically depend on the original concentration in the feed bauxite. At a typical feed concentration of 50 ppm, about 15 percent of the contained gallium is extractable. The remainder reports to the red mud and aluminium hydroxide streams. Gallium is removed from the ion-exchange resin in solution. Electrolysis then gives gallium metal. For semiconductor use, it is further purified with zone melting or single-crystal extraction from a melt (Czochralski process). Purities of 99.9999 percent are routinely achieved and commercially available.

URL of the actual page: https://en.wikipedia.org/wiki/Arsenic#Occurrence_and_production
Title of the Page: Arsenic: Occurrence and production
Editor, Date: Wikipedia, the free encyclopedia
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Arsenic comprises about 1.5 ppm (0.00015 percent) of the Earth's crust, and is the 53rd most abundant element. Typical background concentrations of arsenic do not exceed 3 ng/m3 in the atmosphere; 100 mg/kg in soil; and 10 micrograms/L in freshwater.

Minerals with the formula MAsS and MAs2 (M equals Fe, Ni, Co) are the dominant commercial sources of arsenic, together with realgar (an arsenic sulfide mineral) and native (elemental) arsenic. An illustrative mineral is arsenopyrite (FeAsS), which is structurally related to iron pyrite. Many minor As-containing minerals are known. Arsenic also occurs in various organic forms in the environment.

Arsenic output in 2006:

In 2014, China was the top producer of white arsenic with almost 70 percent world share, followed by Morocco, Russia, and Belgium, according to the British Geological Survey and the United States Geological Survey. Most arsenic refinement operations in the US and Europe have closed over environmental concerns. Arsenic is found in the smelter dust from copper, gold, and lead smelters, and is recovered primarily from copper refinement dust.

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URL of the actual page: https://en.wikipedia.org/wiki/Gallium_arsenide
Title of the Page: Gallium Arsenide
Editor, Date: Wikipedia, the free encyclopedia
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Gallium arsenide (GaAs) is a III-V direct band gap semiconductor with a zinc blende crystal structure.

Gallium arsenide is used in the manufacture of devices such as microwave frequency integrated circuits, monolithic microwave integrated circuits, infrared light-emitting diodes, laser diodes, solar cells and optical windows.

GaAs is often used as a substrate material for the epitaxial growth of other III-V semiconductors, including indium gallium arsenide, aluminum gallium arsenide and others.

URL of the actual page: https://en.wikipedia.org/wiki/Germanium#Applications
Title of the Page: Germanium: Applications
Editor, Date: Wikipedia, the free encyclopedia
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The major end uses for germanium in 2007, worldwide, were estimated to be: 35 percent for fiber-optics, 30 percent infrared optics, 15 percent polymerization catalysts, and 15 percent electronics and solar electric applications. The remaining 5 percent went into such uses as phosphors, metallurgy, and chemotherapy.

Optics:

The notable properties of germania (GeO2) are its high index of refraction and its low optical dispersion. These make it especially useful for wide-angle camera lenses, microscopy, and the core part of optical fibers. It has replaced titania as the dopant for silica fiber, eliminating the subsequent heat treatment that made the fibers brittle. At the end of 2002, the fiber optics industry consumed 60 percent of the annual germanium use in the United States, but this is less than 10 percent of worldwide consumption. GeSbTe is a phase change material used for its optic properties, such as that used in rewritable DVDs.

Electronics:

Silicon-germanium alloys are rapidly becoming an important semiconductor material for high-speed integrated circuits. Circuits utilizing the properties of Si-SiGe junctions can be much faster than those using silicon alone. Silicon-germanium is beginning to replace gallium arsenide (GaAs) in wireless communications devices. The SiGe chips, with high-speed properties, can be made with low-cost, well-established production techniques of the silicon chip industry.

- Other uses
- Germanium and health

URL of the actual page: https://en.wikipedia.org/wiki/Germanium#Occurrence
Title of the Page: Germanium: Occurrence
Editor, Date: Wikipedia, the free encyclopedia
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Germanium is created by stellar nucleosynthesis, mostly by the s-process in asymptotic giant branch stars. The s-process is a slow neutron capture of lighter elements inside pulsating red giant stars.  Germanium has been detected in some of the most distant stars and in the atmosphere of Jupiter.

Germanium's abundance in the Earth's crust is approximately 1.6 ppm. Only a few minerals like argyrodite, briartite, germanite, renierite and sphalerite contain appreciable amounts of germanium. Only few of them (especially germanite) are, very rarely, found in mineable amounts. Some zinc-copper-lead ore bodies contain enough germanium to justify extraction from the final ore concentrate. An unusual natural enrichment process causes a high content of germanium in some coal seams, discovered by Victor Moritz Goldschmidt during a broad survey for germanium deposits. The highest concentration ever found was in Hartley coal ash with as much as 1.6 percent germanium. The coal deposits near Xilinhaote, Inner Mongolia, contain an estimated 1600 tonnes of germanium.

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URL of the actual page: https://www.usgs.gov/centers/nmic/gallium-statistics-and-information
Title of the Page: Gallium Statistics and Information
Editor, Date: National Minerals Information Center
Description of the Page :

Gallium is not produced in the United States, and demand is satisfied by imports, primarily high-purity material from France and low-purity material from Kazakhstan and Russia.   More than 95 percent of gallium consumed in the United States is in the form of gallium arsenide (GaAs).   Analog integrated circuits are the largest application for gallium, with optoelectronic devices (mostly laser diodes and light-emitting diodes) as the second largest end use.

URL of the actual page: https://en.wikipedia.org/wiki/Arsenic#Environmental_issues
Title of the Page: Arsenic: Environmental Issues
Editor, Date: Wikipedia, the free encyclopedia
Description of the Page :

Exposure:

Naturally occurring sources of human exposure include volcanic ash, weathering of minerals and ores, and mineralized groundwater. Arsenic is also found in food, water, soil, and air. Arsenic is absorbed by all plants, but is more concentrated in leafy vegetables, rice, apple and grape juice, and seafood. An additional route of exposure is inhalation of atmospheric gases and dusts. During the Victorian era, arsenic was widely used in home decor, especially wallpapers.

Occurrence in drinking water:

Extensive arsenic contamination of groundwater has led to widespread arsenic poisoning in Bangladesh and neighboring countries. It is estimated that approximately 57 million people in the Bengal basin are drinking groundwater with arsenic concentrations elevated above the World Health Organization's standard of 10 parts per billion (ppb). However, a study of cancer rates in Taiwan suggested that significant increases in cancer mortality appear only at levels above 150 ppb. The arsenic in the groundwater is of natural origin, and is released from the sediment into the groundwater, caused by the anoxic conditions of the subsurface. 

- Redox transformation of arsenic in natural waters:

Arsenic is unique among the trace metalloids and oxyanion-forming trace metals (e.g. As, Se, Sb, Mo, V, Cr, U, Re).

- Wood preservation in the US

URL of the actual page: https://www.cnbc.com/2019/03/14/california-leads-way-as-us-installs-over-10-gigawatts-of-solar-in-2018.html
Title of the Page: California leads the way as US installs more than 10 gigawatts of solar power in 2018
Editor, Date: CNBC, MAR 14 2019
Description of the Page :

- Solar photovoltaic installations dropped 2 percent when compared to 2017.

- California remains a powerhouse when it comes to solar in the U.S., installing more than 3.3 gigawatts of capacity.


The U.S. installed 10.6 gigawatts (GW) of solar photovoltaic capacity in 2018, according to a new report from Wood Mackenzie Power & Renewables and the Solar Energy Industries Association (SEIA).

This represents a 2 percent drop compared to 2017. In a statement Wednesday, the SEIA’s president and CEO, Abigail Ross Hopper, said the solar industry had experienced "growing pains in 2018" that were caused, in large part, by the imposition of tariffs on solar cells and modules. Photovoltaic refers to a way of directly converting light from the sun into electricity.

Ross Hopper went on to add that there was nevertheless reason for optimism. "The total amount of solar installed in America is on track to more than double in the next five years, proving solar's resiliency and its economic strength," she said. "It’s clear, this next decade is going to be one of significant growth."

URL of the actual page: https://twitter.com/herodote63/status/1175701936970051584
Title of the Page: Untitled
Editor, Date: Herodote63, 22 sept. 2019
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URL of the actual page: https://www.cnbc.com/2019/03/07/microsoft-to-buy-energy-from-solar-power-facility-in-north-carolina.html
Title of the Page: Microsoft to buy energy from 74-megawatt solar power facility in North Carolina
Editor, Date: CNBC, MAR 7 2019
Description of the Page :

- The Wilkinson Solar Energy Center is due to commence commercial operations in 2019.

- The deal means that Microsoft’s renewable energy portfolio will stand at more than 1.3 gigawatts. 

Microsoft has signed a 15-year power purchase agreement for the energy produced by a 74-megawatt solar power facility in North Carolina.

The Wilkinson Solar Energy Center will be built, owned and operated by Invenergy, the companies said in a joint announcement Wednesday.

The deal means that Microsoft’s renewable energy portfolio will stand at more than 1.3 gigawatts, the statement added.

The new facility is due to commence commercial operations in 2019, while it’s estimated that more than 500 jobs are set to be created during its construction.

URL of the actual page: https://twitter.com/herodote63/status/1175702196878487553?ref_src=twsrc%5Etfw
Title of the Page: Untitled
Editor, Date: Herodote63, 22 sept. 2019
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URL of the actual page: https://www.cnbc.com/2019/09/19/jeff-bezos-speaks-about-amazon-sustainability-in-washington-dc.html
Title of the Page: Jeff Bezos unveils sweeping plan to tackle climate change
Editor, Date: CNBC, SEP 19 2019
Description of the Page :

- Amazon CEO Jeff Bezos says Amazon is committed to meet the goals of the Paris climate agreement 10 years early.

- As part of the plan, Amazon has agreed to purchase 100,000 electric delivery vans from vehicle manufacturer Rivian.

- Bezos expects 80 percent of Amazon’s energy use to come from renewable sources by 2024, before transitioning to zero emissions by 2030.

Amazon CEO Jeff Bezos unveiled a sweeping new plan on Thursday to tackle climate change, committing the retail giant to meet the goals of the Paris climate agreement 10 years ahead of schedule.

In what he is calling the “Climate Pledge,” Bezos also promised to measure and report the company’s emissions on a regular basis, implement decarbonization strategies and alter its business strategies to offset remaining emissions.

Bezos expects 80 percent of Amazon’s energy use to come from renewable sources by 2024, up from a current rate of 40 percent, before transitioning to zero emissions by 2030.

URL of the actual page: https://www.cnbc.com/2019/03/22/electric-taxis-in-oslo-to-be-charged-using-wireless-technology.html
Title of the Page: Electric taxis in Oslo to be charged using wireless technology
Editor, Date: CNBC, MAR 22 2019
Description of the Page :

- The project will use induction technology, with charging plates installed in areas where taxis park.

- All taxis in Oslo are set to be zero-emission from 2023.


Taxis in the Norwegian capital, Oslo, are set to use wireless fast-charging technology to keep them running.

In an announcement Thursday, Finnish energy firm Fortum said it would work with the City of Oslo and Momentum Dynamics, a U.S. company, to build the system.

The project will use induction technology, with charging plates installed in areas where taxis, which will carry a receiver for the charging, park.

“We will install the wireless chargers at taxi stands, such as the one at... Oslo Central Station,” Annika Hoffner, the head of Fortum Charge and Drive, said in a statement.

URL of the actual page: https://www.cnbc.com/2019/04/08/fitch-says-chinese-electric-vehicle-sales-to-boom-despite-subsidy-cuts.html
Title of the Page: China’s electric vehicle sales will continue boom despite subsidy cuts, Fitch says
Editor, Date: CNBC, APR 8 2019
Description of the Page :

- Electric car sales in China jumped almost 62 percent in 2018 according to official figures.

- But Beijing is set to reduce its subsidies to buyers.

- But Fitch Ratings says the showroom price will likely remain at a similar level.


Booming growth in China’s electric vehicle (EV) market won’t slow because of Beijing’s drastic reduction in subsidies, according to Fitch Ratings.

Electric car sales in China jumped almost 62 percent in 2018 to 1.3 million vehicles, according to China’s Association of Automobile Manufacturers. The same organization sees electric vehicle sales hitting 1.6 million this year.

But the Chinese government has recently raised the bar for electric cars that qualify for subsidies and reduced the amount it is willing to provide to relevant companies.

URL of the actual page: https://twitter.com/herodote63/status/1175707877945880576?ref_src=twsrc%5Etfw
Title of the Page: Untitled
Editor, Date: Herodote63, 22 sept. 2019
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URL of the actual page: https://en.wikipedia.org/wiki/Solar_panels_on_spacecraft
Title of the Page: Solar Panels on Spacecraft
Editor, Date: Wikipedia, the free encyclopedia
Description of the Page :

Spacecraft operating in the inner Solar System usually rely on the use of photovoltaic solar panels to derive electricity from sunlight. Outside the orbit of Jupiter, solar radiation is too weak to produce sufficient power within current solar technology and spacecraft mass limitations, so radioisotope thermoelectric generators (RTGs) are instead used as a power source.

URL of the actual page: https://twitter.com/herodote63/status/1175702196878487553
Title of the Page: Untitled
Editor, Date: Herodote63, 22 sept. 2019
Description of the Page :

URL of a previously posted tweet.

URL of the actual page: http://snaptrends.com/8-mind-blowing-facts-us-geospatial-industry/
Title of the Page: 8 mind blowing facts about the US geospatial-industry
Editor, Date: snaptrends.com
Description of the Page :

The page is no longer available.

Suggested page:

https://www.geospatialworld.net/blogs/what-is-geospatial-industry/

URL of the actual page: https://www.cnbc.com/2019/09/21/the-rise-of-solar-power.html
Title of the Page: The solar industry has grown exponentially thanks to plain old solar panels
Editor, Date: CNBC, SEP 21 2019
Description of the Page :

Elon Musk may have promised the world Tesla solar roof tiles in 2016, but turns out the solar industry may not need the upgrade.

The industry has been growing exponentially thanks to plain old solar panels. You can see the evidence both on people’s rooftops and in the desert, where utility-scale solar plants are increasingly popping up. Here in the U.S., of all new power capacity added to the grid in 2018, about 30 percent was from solar.

But the picture is not all rosy. Solar power is intermittent. The sun isn’t always shining, and the price of storage solutions like lithium ion batteries is still relatively high.

URL of the actual page: https://twitter.com/herodote63/status/1175688826859261953?ref_src=twsrc%5Etfw
Title of the Page: Untitled
Editor, Date: Herodote63, 22 sept. 2019
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URL of the actual page: https://twitter.com/herodote63/status/1156125887785517056?ref_src=twsrc%5Etfw
Title of the Page: Untitled
Editor, Date: Herodote63, 30 juil. 2019
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URL of the actual page: https://www.globalminingreview.com/finance-business/24072019/battery-raw-materials-to-face-supply-crunch-by-mid-2020s/
Title of the Page: Battery raw materials to face supply crunch by mid-2020s?
Editor, Date: Herodote63, 22 sept. 2019
Description of the Page :

The electrification of transport is redefining a number of metals markets. As the world sees demand for batteries grow at an unprecedented rate, battery metals – cobalt, lithium and nickel – could face a supply crunch by the mid-2020s, according to Wood Mackenzie’s ‘Global battery raw materials long-term outlook H1 2019’.

Total passenger electric vehicle (EV) car sales, including hybrid electric vehicles (HEV), were up by over 24 percent last year. Although HEVs had the smallest growth, they made up over 60 percent of EV sales. Wood Mackenzie expects global electric car sales (with a plug) to account for 7 percent of all passenger car sales by 2025, 14 percent by 2030 and 38 percent by 2040.

Gavin Montgomery, Wood Mackenzie Research Director stated: “Battery pack sizes continue to trend larger through the medium-term, resulting in overall greater battery demand. We have seen the first announcements of the commercialisation of NMC 811 cells in EVs. Unsurprisingly, China was the first mover here, but the likes of SK Innovation are intent on the mass production of 811 cells before the end of 2019. While still conservative on mass market uptake for these cells, we are more optimistic in regards to adoption. As such, we expect to see an increased nickel demand at the expense of cobalt, and to a lesser extent, lithium.

“It’s true that most automotive manufacturers plan to go completely electric by 2050. However, unless battery technology can be developed, tested, commercialised, manufactured and integrated into EVs and their supply chains faster than ever before, it will be impossible for many EV targets and ICE bans to be achieved – posing issues for current EV adoption rate projections.”

URL of the actual page: https://en.wikipedia.org/wiki/Photovoltaics
Title of the Page: Photovoltaics
Editor, Date: Wikipedia, the free encyclopedia
Description of the Page :

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 utilized for electricity generation and as photosensors.

A photovoltaic system employs solar modules, each comprising a number of solar cells, which generate electrical power. PV installations may be ground-mounted, rooftop-mounted, wall-mounted or floating. The mount may be fixed or use a solar tracker to follow the sun across the sky.

PV has become the cheapest source of electrical power in regions with a high solar potential, with a bid for pricing as low as 0.01567 US Dollar/kWh in Qatar in 2020. Panel prices have dropped by the factor of 4 between 2004 and 2011. This competitiveness opens the path to a global transition to sustainable energy, which would be required to help mitigate global warming. The emissions budget for CO2 to meet the 1.5 degree target would be used up in 2028 if emissions remain on the current level. However, the use of PV as a main source requires energy storage systems or global distribution by high-voltage direct current power lines causing additional costs, as well as a number of other specific disadvantages such as unstable power generation and the requirement for power companies to compensate for too much solar power in the supply mix by having more reliable conventional power supplies in order to regulate demand peaks and potential undersupply.

URL of the actual page: https://twitter.com/herodote63/status/1175722146334728193?ref_src=twsrc%5Etfw
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URL of the actual page: https://twitter.com/herodote63/status/1175716560645885954
Title of the Page: Untitled
Editor, Date: Herodote63, 22 sept. 2019
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URL of the actual page: https://en.wikipedia.org/wiki/Solar_cell#Materials
Title of the Page: Solar Cell: Materials
Editor, Date: Wikipedia, the free encyclopedia
Description of the Page :

Solar cells are typically named after the semiconducting material they are made of. These materials must have certain characteristics in order to absorb sunlight. Some cells are designed to handle sunlight that reaches the Earth's surface, while others are optimized for use in space. Solar cells can be made of only one single layer of light-absorbing material (single-junction) or use multiple physical configurations (multi-junctions) to take advantage of various absorption and charge separation mechanisms.

Solar cells can be classified into first, second and third generation cells. The first generation cells—also called conventional, traditional or wafer-based cells—are made of crystalline silicon, the commercially predominant PV technology, that includes materials such as polysilicon and monocrystalline silicon. Second generation cells are thin film solar cells, that include amorphous silicon, CdTe and CIGS cells and are commercially significant in utility-scale photovoltaic power stations, building integrated photovoltaics or in small stand-alone power system. The third generation of solar cells includes a number of thin-film technologies often described as emerging photovoltaics—most of them have not yet been commercially applied and are still in the research or development phase. Many use organic materials, often organometallic compounds as well as inorganic substances. Despite the fact that their efficiencies had been low and the stability of the absorber material was often too short for commercial applications, there is a lot of research invested into these technologies as they promise to achieve the goal of producing low-cost, high-efficiency solar cells.

URL of the actual page: https://en.wikipedia.org/wiki/Photovoltaic_effect
Title of the Page: Photovoltaic Effect
Editor, Date: Wikipedia, the free encyclopedia
Description of the Page :

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.

The photovoltaic effect is closely related to the photoelectric effect. For both phenomena, light is absorbed, causing excitation of an electron or other charge carrier to a higher-energy state. The main distinction is that the term photoelectric effect is now usually used when the electron is ejected out of the material (usually into a vacuum) and photovoltaic effect used when the excited charge carrier is still contained within the material. In either case, an electric potential (or voltage) is produced by the separation of charges, and the light has to have a sufficient energy to overcome the potential barrier for excitation. The physical essence of the difference is usually that photoelectric emission separates the charges by ballistic conduction and photovoltaic emission separates them by diffusion, but some "hot carrier" photovoltaic device concepts blur this distinction.

The first demonstration of the photovoltaic effect, by Edmond Becquerel in 1839, used an electrochemical cell. He explained his discovery in Comptes rendus de l'Académie des sciences, "the production of an electric current when two plates of platinum or gold immersed in an acid, neutral, or alkaline solution are exposed in an uneven way to solar radiation."

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Editor, Date: Herodote63, 22 sept. 2019
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URL of a previously posted tweet.

URL of the actual page: https://en.wikipedia.org/wiki/Thin-film_solar_cell#Materials
Title of the Page: Materials
Editor, Date: Wikipedia, the free encyclopedia
Description of the Page :

Thin-film technologies reduce the amount of active material in a cell. Most sandwich active material between two panes of glass. Since silicon solar panels only use one pane of glass, thin film panels are approximately twice as heavy as crystalline silicon panels, although they have a smaller ecological impact (determined from life cycle analysis). The majority of film panels have 2-3 percentage points lower conversion efficiencies than crystalline silicon. Cadmium telluride (CdTe), copper indium gallium selenide (CIGS) and amorphous silicon (a-Si) are three thin-film technologies often used for outdoor applications.

- Cadmium telluride
- Copper indium gallium selenide
- Silicon
- Gallium arsenide

URL of the actual page: https://en.wikipedia.org/wiki/Copper_indium_gallium_selenide_solar_cells
Title of the Page: Copper indium gallium selenide solar cells
Editor, Date: Wikipedia, the free encyclopedia
Description of the Page :

A copper indium gallium selenide solar cell (or CIGS cell, sometimes CI(G)S or CIS 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 and selenium 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.

CIGS is one of three mainstream thin-film photovoltaic (PV) technologies, the other two being cadmium telluride and amorphous silicon. Like these materials, CIGS layers are thin enough to be flexible, allowing them to be deposited on flexible substrates. However, as all of these technologies normally use high-temperature deposition techniques, the best performance normally comes from cells deposited on glass, even though advances in low-temperature deposition of CIGS cells have erased much of this performance difference. CIGS outperforms polysilicon at the cell level, however its module efficiency is still lower, due to a less mature upscaling.

Thin-film market share is stagnated at around 15 percent, leaving the rest of the PV market to conventional solar cells made of crystalline silicon. In 2013, the market share of CIGS alone was about 2 percent and all thin-film technologies combined fell below 10 percent. CIGS cells continue being developed, as they promise to reach silicon-like efficiencies, while maintaining their low costs, as is typical for thin-film technology.

URL of the actual page: https://en.wikipedia.org/wiki/Amorphous_silicon#Photovoltaics
Title of the Page: Amorphous Silicon: Photovoltaics
Editor, Date: Wikipedia, the free encyclopedia
Description of the Page :

Amorphous silicon (a-Si) has been used as a photovoltaic solar cell material for devices which require very little power, such as pocket calculators, because their lower performance compared to conventional crystalline silicon (c-Si) solar cells is more than offset by their simplified and lower cost of deposition onto a substrate. The first solar-powered calculators were already available in the late 1970s, such as the Royal Solar 1, Sharp EL-8026, and Teal Photon.

More recently, improvements in a-Si construction techniques have made them more attractive for large-area solar cell use as well. Here their lower inherent efficiency is made up, at least partially, by their thinness – higher efficiencies can be reached by stacking several thin-film cells on top of each other, each one tuned to work well at a specific frequency of light. This approach is not applicable to c-Si cells, which are thick as a result of its indirect band-gap and are therefore largely opaque, blocking light from reaching other layers in a stack.

The source of the low efficiency of amorphous silicon photovoltaics is due largely to the low hole mobility of the material. This low hole mobility has been attributed to many physical aspects of the material, including the presence of dangling bonds (silicon with 3 bonds), floating bonds (silicon with 5 bonds), as well as bond reconfigurations. While much work has been done to control these sources of low mobility, evidence suggests that the multitude of interacting defects may lead to the mobility being inherently limited, as reducing one type of defect leads to formation others.

URL of the actual page: https://en.wikipedia.org/wiki/Cadmium_telluride_photovoltaics
Title of the Page: Cadmium telluride photovoltaics
Editor, Date: Wikipedia, the free encyclopedia
Description of the Page :

Cadmium telluride (CdTe) photovoltaics describes a photovoltaic (PV) technology that is 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.

On a lifecycle basis, CdTe PV has the smallest carbon footprint, lowest water use and shortest energy payback time of any current photo voltaic technology. CdTe's energy payback time of less than a year allows for faster carbon reductions without short-term energy deficits.

The toxicity of cadmium is an environmental concern mitigated by the recycling of CdTe modules at the end of their life time, though there are still uncertainties regarding the recycling of CdTe modules and the public opinion is skeptical towards this technology. The usage of rare materials may also become a limiting factor to the industrial scalability of CdTe technology in the mid-term future. The abundance of tellurium—of which telluride is the anionic form—is comparable to that of platinum in the earth's crust and contributes significantly to the module's cost.

URL of the actual page:
Title of the Page: Crystalline silicon
Editor, Date: Wikipedia, the free encyclopedia
Description of the Page :

Crystalline silicon (c-Si) is the crystalline forms of silicon, either polycrystalline silicon (poly-Si, consisting of small crystals), or monocrystalline silicon (mono-Si, a continuous crystal). Crystalline silicon is the dominant semiconducting material used in photovoltaic technology for the production of solar cells. These cells are assembled into solar panels as part of a photovoltaic system to generate solar power from sunlight.

In electronics, crystalline silicon is typically the monocrystalline form of silicon, and is used for producing microchips. This silicon contains much lower impurity levels than those required for solar cells. Production of semiconductor grade silicon involves a chemical purification to produce hyperpure polysilicon followed by a recrystallization process to grow monocrystalline silicon. The cylindrical boules are then cut into wafers for further processing.

Solar cells made of crystalline silicon are often called conventional, traditional, or first generation solar cells, as they were developed in the 1950s and remained the most common type up to the present time. Because they are produced from 160–190 micrometers thick solar wafers—slices from bulks of solar grade silicon—they are sometimes called wafer-based solar cells.

URL of the actual page: https://twitter.com/herodote63/status/1175722428028375040?ref_src=twsrc%5Etfw
Title of the Page: Untitled
Editor, Date: Herodote63, 22 sept. 2019
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URL of the actual page: https://twitter.com/herodote63/status/1175701378989219841
Title of the Page: Untitled
Editor, Date: Herodote63, 22 sept. 2019
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URL of a previously posted tweet.

URL of the actual page: https://www.cnbc.com/2019/05/09/solar-installations-in-us-exceed-2-million-and-could-double-by-2023.html
Title of the Page: Solar installations in US now exceed 2 million and could double by 2023, new figures show
Editor, Date: CNBC, MAY 9 2019
Description of the Page :

- California was responsible for 51 percent of the first million installations and 43 percent of the second million.

- Other states including Texas, Rhode Island, Florida, Utah and Maryland have helped to drive growth.

There are now over 2 million solar photovoltaic (PV) installations in the U.S., according to new figures. The 2 million mark comes three years after installations hit 1 million, a figure it took the industry 40 years to reach.

The numbers, from Wood Mackenzie Power & Renewables and the Solar Energy Industries Association (SEIA), were released Thursday.

Solar power can be harnessed in several ways, including through photovoltaic and concentrated solar power systems. Photovoltaic refers to a way of directly converting light from the sun into electricity.

California was responsible for 51 percent of the first million installations and 43 percent of the second million, the SEIA said. It explained that this reduction was “in large part” down to a residential sector that was both growing and “rapidly diversifying across state markets.”

URL of the actual page: https://www.cnbc.com/2019/04/26/women-entrepreneurs-are-selling-solar-power-to-homes-in-rural-india.html
Title of the Page: Thousands of women entrepreneurs are selling solar powered tech to homes in rural India
Editor, Date: CNBC, APR 26 2019
Description of the Page :

- For many people across the world, the inability to access or pay for energy is a pressing issue that makes life challenging.

- In India, Frontier Markets wants to broaden rural communities’ access to clean sources of energy using what it describes as an entrepreneurial model.


With just the flick of a switch most of us can enjoy instant light and heat without a second thought.

Yet for many people across the world, the inability to access or pay for energy is a pressing issue that makes life far more challenging. The International Energy Agency (IEA) defines energy poverty as a “lack of access to modern energy services.”

The IEA defines such services as “household access to electricity and to clean cooking facilities”, the latter referring to fuels and stoves that do not generate damaging air pollution within homes.

In 2017, almost 2.7 billion people around the world lacked access to clean cooking facilities, while 992 million did not have access to electricity, according to the IEA.

URL of the actual page: https://www.cnbc.com/2019/07/12/londoners-are-installing-solar-panels-on-their-apartment-blocks.html
Title of the Page: Londoners are getting together to install solar panels on their apartment blocks
Editor, Date: CNBC, JUL 12 2019
Description of the Page :

- Repowering London is a not-for-profit that specializes in community-owned renewable energy projects.

- The organization’s model lets local communities invest in solar power projects.

- Many of these solar projects are installed on the rooftops of apartments. 


From vast offshore wind farms to huge solar parks, the planet is home to some huge renewable energy facilities. Yet smaller, local projects can have an equally important impact on people and the planet.

Repowering London is a not-for-profit which says it specializes in “facilitating the co-production of community-owned renewable energy projects.”

By working with both community groups and local authorities it aims to, among other things, cut carbon dioxide emissions through the production of de-centralized, low-carbon energy; fight fuel poverty; and generate training and employment opportunities for communities.

URL of the actual page: https://www.cnbc.com/2019/05/03/how-your-smart-watch-could-soon-be-powered-by-small-solar-cells.html
Title of the Page: How your smart watch could soon be powered by small solar cells
Editor, Date: CNBC, MAY 3 2019
Description of the Page :

- Today, a range of sources, from traditional fossil fuels to wind and solar are being used to power the planet.

- In Jerusalem, one business wants to make photovoltaic technology an integral part of our day to day lives.


The world’s energy mix is changing. Today, a range of sources, from traditional fossil fuels to wind, biofuels and solar are being used to power the planet.

One way of turning solar energy into electricity is through using solar photovoltaic technology. Photovoltaic refers to a way of directly converting light from the sun into electricity.

The International Energy Agency (IEA) describes photovoltaics as being a “very modular technology” that can be rolled out in “very small quantities at a time.” This means that systems can be small – used on calculators, for example – or large scale.

URL of the actual page: https://www.cnbc.com/2019/07/17/dubai-international-airport-installs-15000-solar-panels.html
Title of the Page: Dubai International airport installs 15,000 solar panels
Editor, Date: CNBC, JUL 17 2019
Description of the Page :

- Dubai Airports says the system will produce 7,483,500 kilowatt hours of energy per year.

- This will help to cut carbon emissions by more than 3,000 metric tonnes annually. 


A solar energy system made up of 15,000 photovoltaic panels has been installed at Dubai International airport.

In an announcement earlier this week, Dubai Airports said the system would produce 7,483,500 kilowatt hours of energy per year, helping to cut carbon dioxide emissions by 3,243 metric tonnes.

Etihad Energy Services Company, a wholly-owned subsidiary of the Dubai Electricity and Water Authority, was involved in the project’s installation.

Michael Ibbitson, who is executive vice president for Infrastructure and Business Technology at Dubai Airports, said in a statement that a number of initiatives had been undertaken to limit its carbon footprint.

URL of the actual page: https://twitter.com/herodote63/status/1175701936970051584?ref_src=twsrc%5Etfw
Title of the Page: Untitled
Editor, Date: Herodote63, 22 sept. 2019
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