Insolation defined

Insolation (from INcoming SOLar radiATION) is a measure of solar energy received on a given surface area in a given time. It is commonly expressed in kilowatt-hours per square meter per day (kW•h/m²/day). The surface may be a planet or a terrestrial object inside the atmosphere, or any object exposed to solar rays including spacecraft. Some of the solar radiation will be absorbed, causing radiant heating of the object, and the remainder will be reflected. The proportion of radiation reflected or absorbed depends on the object's reflectivity or albedo. Sometimes, as in the text below, a long-term average intensity of incoming solar radiation will be given in units such as watts per square meter (W/m² or Wm^-2) and called insolation, with the duration (such as daily, annual, or historical) stated or only implied.

Month by month solar radiation for Chennai

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	* * * * *	AC Energy & Cost Savings	* * * * *

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Station Identification City: Madras Country/Province: IND   Latitude: 13.00° N Longitude:     80.18° E Elevation: 16 m Weather Data:     IWEC PV System Specifications DC Rating: 4.00 kW DC to AC Derate Factor: 0.770 AC Rating: 3.08 kW Array Type: Fixed Tilt   Array Tilt: 13.0° Array Azimuth: 180.0° Energy Specifications Energy Cost:     1.8400 rupee/kWh		Results Month   Solar Radiation (kWh/m2/day) AC Energy (kWh) Energy Value (rupee) 1  5.55      472  868.48  2  6.40      485  892.40  3  6.68      553  1017.52  4  6.71      532  978.88  5  6.12      502  923.68  6  5.36      426  783.84  7  4.71      392  721.28  8  4.91      408  750.72  9  5.46      437  804.08  10  5.08      427  785.68  11  4.54      377  693.68  12  4.65      398  732.32  Year  5.51      5410  9954.40

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About the Hourly Performance Data
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