Science tells us that every square meter of the earth’s surface, when exposed to direct sunlight, receives about 1000 watts (1 kilowatt) of energy from the sun’s light. Depending on the angle of sunlight, which changes with the time of day, and the geographical location, the power of the sun’s light will be somewhat more or less than 1 kilowatt-hour per hour for every square meter of the earth’s surface exposed to the sun. Of this solar energy, about 523 watts is in the infra-red spectrum and the ultra-violet portion accounts for about 27 watts. The remaining 440 watts is produced by the octave comprising the visible range.
The chart pictured below depicts the current state of the art for Photovoltaic (PV) solar cells. PV research focuses on boosting solar cell conversion efficiencies, lowering the cost of solar cells, modules, and systems, and improving the reliability of PV components and systems. Accelerating the integration of PV technology is an essential part of global sustainability. Click on the chart reproduced here for a full size copy.
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