A solar cell is made of two types of semiconductors, called p-type and n-type silicon. The p-type silicon is produced by adding atoms—such as boron or gallium—that have one less electron in their outer energy level than does silicon. Because boron has one less electron than is required to form the bonds with the surrounding silicon atoms, an electron vacancy or “hole” is created.
The n-type silicon is made by including atoms that have one more electron in their outer level than does silicon, such as phosphorus. Phosphorus has five electrons in its outer energy level, not four. It bonds with its silicon neighbor atoms, but one electron is not involved in bonding. Instead, it is free to move inside the silicon structure.
A solar cell consists of a layer of p-type silicon placed next to a layer of n-type silicon (Fig.1). In the n-type layer, there is an excess of electrons, and in the p-type layer, there is an excess of positively charged holes (which are vacancies due to the lack of valence electrons).
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What are the 5 main components of a solar cell?
The 5 Key Components of a Solar Panel System At Green Solar Technologies, we make solar look easy. But have you ever wanted to hear a breakdown of all the components that make up solar panels? Even though it may seem like magic, it’s actually science and engineering. There are 5 key components in a home solar panel system: solar panels, an inverter, an electrical panel, the power grid, and the sun.
Why are solar cells made of silicon?
REASONS WHY SILICON IS USED IS MAKING SOLAR CELLS – Solar panels are made up of Solar Photo-voltaic (PV) cells. The working of a solar energy system IS dependent on the efficiency of the photovoltaic cells. These photovoltaic cells are made using silicon. Here are some reasons why Silicon is used:
Silicon is a, Semiconductors have properties that fall between that of conductor and insulators. It has an electrical property that makes it conductive in one direction and insulating in the other. Semiconductors are photosensitive. Silicon solar cells have recorded an efficiency of over 20%. When Silicon is doped with impurities like gallium and arsenic atoms, its ability to capture the sun’s energy and convert it to electricity is improved considerably. Silicon is non-toxic. Crystalline silicon is a stable material. Silicon has a band gap of 1.1eV, which is not far from the optimal value of 1.34eV for generating power from sunlight. There are other semiconductors with ideal band gaps such as CdTe – 1.49eV but they are more expensive to produce. Silicon is the second most abundant element in the earth’s crust after Oxygen. Silicon is cheap and readily available.
In conclusion, solar cells made from crystalline silicon provide a combination of high efficiency, low cost, and long lifespan. Modules are expected to last for 25 years or more, still producing more than 80% of their original power after this time. Interested in going solar? Want to get the best solar panel for home or business? Keep calm! Contact today.
Can I make a solar cell at home?
How to Make a Very Cheap Homemade Photovoltaic Solar Cell Updated May 29, 2018 By Jason Thompson A solar cell is the fundamental element of a solar panel, a device that converts sunlight into electricity. Professionally made solar cells are made of special semiconductor material sandwiched between metal contacts and a layer of non-reflective glass.
- The semiconductor is specially made to be sensitive to the photoelectric effect and responds to light by releasing a flow of electrons.
- Though these materials are expensive, you can make your own solar cell at home out of materials that are much cheaper and easier to come by.
- A homemade solar cell is perfect for science class demonstrations, science fairs and even powering your own small devices.
A homemade solar cell made of copper sheet and salt water can give insights into the physics of the photoelectric effect. Light a propane torch and hold it in one hand. Pick up a sheet of copper in your other hand, using tongs. Hold the sheet of copper in the flame.
- Heat the copper until the section under the flame has been glowing red hot for at least a minute.
- Set the copper sheet down on a fireproof surface.
- Pick it up with the tongs again, so you can hold a different location and heat a new area with the torch.
- Repeat this process until you have treated a few different spots on the copper sheet.
Place the copper sheet onto your fireproof surface and let it cool to air temperature. The areas that you heated should be blackened, though other colors may be present as well. Strip 1 inch of insulation off of each end of one copper wire with the wire strippers.
- Clamp one end of the wire to the copper sheet, using the alligator clip.
- Make sure that it is clamped to clean, unblackened copper.
- Mix salt into a cup of water until it stops dissolving.
- At this point the salt solution is at maximum strength.
- Place several drops of salt water onto different blackened areas of the copper.
Because of microscopic irregularities on the surface of the copper each drop will produce different results. Strip one end of insulation off each end of the other wire, using the wire strippers. Place one end of this wire into one of the drops of salt solution on the blackened areas of copper.
What metals are used in solar panels?
By weight, 80 percent of a solar panel is glass and aluminum, which is easy to recycle. Solar panels contain the rare elements gallium and indium that can be captured through recycling.
What is inside a solar panel?
A solar panel is essentially an electronic sandwich. The filling is a thin layer of crystalline silicon cells, which are insulated and protected from the elements on both sides by sheets of polymers and glass. It’s all held together in an aluminum frame.
Is solar really green?
Manufacturing Solar Panels – Electricity produced from solar yields no emissions, no greenhouse gases, and no fossil fuels, but it does require a certain amount of energy to make the solar panels. Luckily, the energy they produce far exceeds what it takes to manufacture them.
- The solar power industry pays attention to these details by actively seeking ways to improve this power imbalance.
- In fact, researchers created a metric called Energy Payback Time (EPBT) to measure the length of time it takes a solar panel to generate the amount of energy equal to what it took to be created.
For multicrystalline-silicon systems (i.e. solar panels), it currently takes 4 years to achieve EPBT, according to the U.S. Department of Energy.5 Since solar panels last for 20 to 30 years, a single solar panel can generate more than four or five times the energy used to produce.
Are solar panels made of oil?
How do petrochemicals advance renewable energy? – Solar panels—whether they support, or help power a suburban home—are usually made with the same principle in mind: convert photons from the sun into energy. The photovoltaics, which turn sunlight into energy, are typically sandwiched between layers of copolymers.
- One of the petrochemical building blocks common to many of the copolymers is ethylene—a petrochemical derived from oil and natural gas.
- Solar energy is not alone in its connection to petrochemicals.
- Wind energy—which makes up a little under 7 percent of U.S.
- Energy consumption—relies on petrochemicals such as propylene and xylene for the production of engine houses and rotor blades.
Fossil fuels, and their derived petrochemicals, are at the core of American energy and enable many renewable technologies commonly discussed in “all-of-the-above” approaches to energy. According to (IEA) director Dr. Fatih Birol, “Petrochemicals are one of the key blind spots in the global energy debate The U.S. petrochemical industry has a crucial and enduring role to play in meeting the needs of a growing world population while simultaneously fulfilling the imperative to produce petrochemicals in a sustainable and clean manner. McKinsey released a new report outlining the emissions profiles of plastic vs.
- Non-plastic alternatives in multiple use cases.
- They found that in nearly every case examined, plastics are responsible for less greenhouse gas emissions throughout their lifecycle than alternative materials.
- EPA’s existing Risk Management Plan (RMP) is doing what it was designed to do: drive continual safety improvements across workplaces to keep industry employees, contractors, facility neighbors and local environments safe.
Any changes to a regulation as effective as the RMP need to be solidly evidence-based. Unfortunately, today’s proposal is filled with costly and misinformed changes, with little-to-no data to back them up. In fact, many of the proposed changes will adversely impact the safety and security missions of refining and petrochemical sites.
Are solar panels eco friendly?
Are Solar Panels Eco-Friendly – Environmental Benefits Solar panels are designed to absorb the sun’s rays as a source of energy for generating electricity or heating. The has led many home owners to question if installing solar panels is the right decision for them. That said many wonder are solar panels eco-friendly and do they have a potential for a negative impact on the environment.
Solar panels create no greenhouse gases Solar panels are now not only an option for sunny environments Solar panels are slowly becoming adopted by many big businesses that typically use a lot of energy resources
Solar Energy Impact vs. Fossil Fuels When choosing solar panels you become much more environmentally friendly over power sources that use fossil fuels. The states that each household that switches to solar energy stops 7.7 tons of toxic greenhouse gases from being released,
The biggest concern for most people interested in solar panels is whether the disposal process is harmful to the environment. Manufacturing companies have developed ways to make solar products easier to dispose of, and easier on the environment. Many of the chemicals have great potential for recycling because of their value.
When manufacturers have incentives to recycle these materials, they will keep costs down. New technology also has paved the way for the use of organic products that have less of an environmental impact. If you are thinking of solar power as an option, you will find that it is an eco-friendly choice.
Where does silicon come from?
Chemistry in its element: silicon – (Promo) You’re listening to Chemistry in its element brought to you by Chemistry World, the magazine of the Royal Society of Chemistry. (End promo) Meera Senthilingam For this week’s element we enter the world of science fiction to explore life in outer space.
Here’s Andrea Sella. Andrea Sella When I was about 12, my friends and I went through a phase of reading science fiction. There the were the fantastic worlds of Isaac Asimov, Larry Niven and Robert Heinlein, involving impossible adventures on mysterious planets – the successes of the Apollo space programme at the time only helped us suspend our disbelief.
One of the themes I remember from these stories was the idea that alien life forms, often based around the element silicon, abounded elsewhere in the universe. Why silicon? Well, it is often said that elements close to each other in the periodic table share similar properties and so, seduced by the age-old red herring that “carbon is the element of life”, the writers selected the element below it, silicon.
I was reminded of these readings a couple of weeks ago when I went to see an exhibition of work by a couple of friends of mine. Called “Stone Hole” it consisted of stunning panoramic photographs taken at extremely high resolution inside sea caves in Cornwall. As we wandered through the gallery a thought occurred to me.
“Could one imagine a world without silicon?” Every single photograph was, not surprisingly, dominated by rocks based on silicon and it was a powerful reminder of the fact that silicon is the second most abundant element in the earth’s crust, beaten to first place by oxygen, the element with which it invariable entangled.
Silicate rocks – those in which silicon is surrounded tetrahedrally by four oxygen atoms – exist in an astonishing variety, the differences being determined by how the tetrahedra building blocks link together, and what other elements are present to complete the picture. When the tetrahedra link one to the next, one gets a mad tangle of chains looking like an enormous pot of spaghetti – the sorts of structures one gets in ordinary glass.
The purest of these chain-like materials is silicon dioxide – silica – found quite commonly in nature as the colourless mineral quartz or rock crystal. In good, crystalline quartz, the chains are arranged in beautiful helices and these can all spiral to the left.
Or to the right. When this happens the crystals that result are exact mirror images of each other. But not superimposable – like left and right shoes. To a chemist, these crystals are chiral, a property once thought to be the exclusive property of the element carbon, and chirality, in turn, was imagined to be a fundamental feature of life itself.
Yet here it is, in the cold, inorganic world of silicon. Most grandiose of all, one can make porous 3D structures – a bit like molecular honeycombs – particularly in the presence of other tetrahedral linkers based on aluminium. These spectacular materials are called the zeolites, or molecular sieves.
- By carefully tailoring the synthetic conditions, one can build material in which the pores and cavities have well defined sizes – now you have a material that can be used like a lobster traps, to catch molecules or ions of appropriate size.
- But what of the element itself? Freeing it from oxygen is tough, it hangs on like grim death and requires brutal conditions.
It was Humphrey Davy, the Cornish chemist and showman, who first began to suspect that silica must be a compound, not an element. He applied electric currents to molten alkalis and salts and to his astonishment and delight, isolated some spectacularly reactive metals, including potassium.
He now moved on to see what potassium could do. Passing potassium vapour over some silica he obtained a dark material that he could then burn and convert back to pure silica. Where he pushed, others followed. In France, Thénard and Gay-Lussac carried out similar experiments using silicon fluoride. Within a couple of years, the great Swedish analyst Jöns Jakob Berzelius had isolated a more substantial amount of the material and declared it an element.
Silicon’s properties are neither fish nor fowl. Dark gray in colour and with a very glossy glass-like sheen, it looks like a metal but is in fact quite a poor conductor of electricity, and there in many ways, lies the secret of its ultimate success. The problem is that electrons are trapped, a bit like pieces on a draughts board in which no spaces are free.
What makes silicon, and other semiconductors, special is that it is possible to promote one of the electrons to an empty board – the conduction band – where they can move freely. It’s a bit like the 3-dimensional chess played by the point-eared Dr Spock in Star Trek. Temperature is crucial. Warming a semiconductor, allow some electrons to leap, like salmon, up to the empty conduction band.
And at the same time, the space left behind – known as a hole – can move too. But there is another way to make silicon conduct electricity: it seems perverse, but by deliberately introducing impurities like boron or phosphorus one can subtly change the electrical behaviour of silicon.
Such tricks lie at the heart of the functioning of the silicon chips that allow you to listen to this podcast. In less than 50 years silicon has gone from being an intriguing curiosity to being one of the fundamental elements in our lives. But the question remains, is silicon’s importance simply restricted to the mineral world? The prospects do not seem good – silicate fibres, like those in blue asbestos are just the right size to penetrate deep inside the lungs where they pierce and slash the inner lining of the lungs.
And yet, because of its extraordinary structural variability, silicon chemistry has been harnessed by biological systems. Silicate shards lurk in the spines of nettles waiting to score the soft skin of the unwary hiker and inject minuscule amounts of irritant.
- And in almost unimaginable numbers delicate silicate structures are grown by the many tiny life-forms that lie at the base of marine food chains, the diatoms.
- Could one therefore find silicon-based aliens somewhere in space? My hunch would probably be not.
- Certainly not as the element.
- It is far too reactive and one will always find it associated with oxygen.
But even linked with oxygen, it seems unlikely, or at least not under the kinds of mild conditions that we find on earth. But then again, there is nothing like a surprise to make one think. As the geneticist J B S Haldane put it, “The universe is not queerer than we suppose.
- It is queerer than we can suppose”.
- I live in hope.
- Meera Senthilingam So although unlikely there could be some silicon based surprises lurking out in space.
- That was the ever hopeful Andrea Sella from University College London with the life forming chemistry of silicon.
- Now next week we hear about Roentgenium the element that we need to get just right.
Simon Cotton The idea was to make the nickel ions penetrate the bismuth nucleus, so that the two nuclei would fuse together, making a bigger atom. The energy of the collision had to be carefully controlled, because if the nickel ions were not going fast enough, they could not overcome the repulsion between the two positive nuclei and would just fly off the bismuth on contact.
However, if the nickel ions had too much energy, the resulting “compound nucleus” would have so much excess energy that it could just undergo fission and fall apart. The trick was, like Goldilocks’ porridge, to be “just right”, so that the fusion of the nuclei would occur, just. Meera Senthilingam And join Simon Cotton to find out how successful collisions were created by the founders of the element roentgenium in next week’s Chemistry in its Element.
Until then I’m Meera Senthilingam and thank you for listening. (Promo) Chemistry in its element is brought to you by the Royal Society of Chemistry and produced by thenakedscientists.com, There’s more information and other episodes of Chemistry in its element on our website at chemistryworld.org/elements,