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Solar panels giv

The installation of solar panels in remote locations is usually much more cost effective than laying the required high voltage wires.

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Solar energy is the cleanest and most abundant renewable energy source available, and the U.S. has some of the richest solar resources in the world. Modern technology can harness this energy for a variety of uses, including generating electricity, providing light or a comfortable interior environment, and heating water for domestic, commercial, or industrial use. The U.S. solar market faces both challenges and opportunities; the industry is working to scale up the production of solar technology, and drive down manufacturing and installation costs. There are several ways to harness solar energy: photovoltaics (also called solar electric), solar heating & cooling, concentrating solar power (typically built at utility-scale), and passive solar. The first three are active solar systems, which use mechanical or electrical devices that convert the sun's heat or light to another form of usable energy. Passive solar buildings are designed and oriented to collect, store, and distribute the heat energy from sunlight to maintain the comfort of the occupants without the use of moving parts or electronics. Solar energy is a flexible energy technology: solar power plants can be built as distributed generation (located at or near the point of use) or as a central-station, utility-scale solar power plant (similar to traditional power plants). Some utility-scale solar plants can store the energy they produce for use after the sun sets. 

Solar energy is a renewable energy source. This means that we cannot run out of solar energy, as opposed to non-renewable energy sources (e.g. fossil fuels, coal and nuclear).

Solar energy is available all over the world.

Harnessing solar energy does generally not cause pollution.

Today's PV devices convert 7%-17% of light energy into electric energy. Of course, the other side of the equation is the money it costs to manufacture the PV devices. This has been improved over the years as well. In fact, today's PV systems produce electricity at a fraction of the cost of early PV systems.

Simply put, a solar panel works by allowing photons, or particles of light, to knock electrons free from atoms, generating a flow of electricity. Solar panels actually comprise many, smaller units called photovoltaic cells. (Photovoltaic simply means they convert sunlight into electricity.) Many cells linked together make up a solar panel. Each photovoltaic cell is basically a sandwich made up of two slices of semi-conducting material, usually silicon — the same stuff used in microelectronics.

Conventional photovoltaic cells used in flat-plate collectors convert about 15% of the sunlight that reaches them into electricity. Those single-junction cells are used in typical rooftop PV panels because they’re relatively inexpensive. One reason for their inefficiency is that they only absorb a narrow band of optical wavelengths. Multijunction cells consist of several layers, each tuned to a particular wavelength of light. As shown below, each layer has a peak efficiency at a certain wavelength, making the combination of layers in the multijunction cell efficient over a wider range of wavelengths. “External Quantum Efficiency” is the ratio of charge carriers (free electrons) to the number of photons that reach the cell. In other words, it’s a measure of how many electrons are “knocked free” by incoming photons.

How does a solar cell turn sunlight into electricity? In a crystal, the bonds [between silicon atoms] are made of electrons that are shared between all of the atoms of the crystal. The light gets absorbed, and one of the electrons that's in one of the bonds gets excited up to a higher energy level and can move around more freely than when it was bound. That electron can then move around the crystal freely, and we can get a current.