What is the rate of solar energy reaching the Earth surface anddifference between the energy received by the places far from the equator and near the equator?
At Earth's average distance from the Sun (about 150 million kilometers), the average intensity of solar energy reaching the top of the atmosphere directly facing the Sun is about 1,360 watts per square meter, according to measurements made by the most recent NASA satellite missions. In the Polar Regions, the sun rays are slanting. They are spread on a larger area. Hence, places near the Equator receive more heat and are hotter.
The reference solar spectrum considered by vast majority of researchers is the AM1.5 solar spectrum published by NREL and can be found here: https://www.nrel.gov/grid/solar-resource/spectra-am1.5.html
Of course there is going to be a difference in the irradiance depending on your location on Earth but by everyone using the same solar spectrum to analyse the solar cell performance, we can make a fair comparison between systems.
The equator is closer to the sun and sun's rays travel through more atmosphere at the equator. The sun's energy is more spread out at the equator and sun's rays hit the earth's surface at a higher angle at the equator. In the Polar Regions, the sun rays are slanting. They are spread on a larger area. Hence, places near the Equator receive more heat and are hotter. Areas around the equator absorbed about 200 watts per square meter more on average than they reflected or radiated. Areas near the poles reflected and/or radiated about 200 more watts per square meter than they absorbed. Mid-latitudes were roughly in balance. Sunlight hits the Earth most directly at the Equator. The curve of the Earth means that sunlight is spread over a wider area the further you move from the Equator. Sunlight hits a smaller surface area at the Equator so heats up quickly compared to the poles. The sun's rays are the most concentrated around the equator. Moving north or south of the equator, the sun's rays are spread over a larger area, so each square meter of Earth's surface receives less solar energy. This is because of the angle of the sun's rays as they strike Earth's curved surface. At Earth's average distance from the Sun (about 150 million kilometers), the average intensity of solar energy reaching the top of the atmosphere directly facing the Sun is about 1,360 watts per square meter. The solar constant is the amount of heat energy received per second per unit area of a perfectly black surface placed at a mean distance of the Earth from the Sun, in the absence of Earth’s atmosphere, the surface being held perpendicular to the direction of Sun’s rays. Its value is 1388 W/m2.
At Earth's average distance from the Sun (about 150 million kilometers), the average intensity of solar energy reaching the top of the atmosphere directly facing the Sun is about 1,360 watts per square meter, according to measurements made by the most recent NASA satellite missions. Areas around the equator absorbed about 200 watts per square meter more on average (orange and red) than they reflected or radiated. Areas near the poles reflected and/or radiated about 200 more watts per square meter than they absorbed. Mid-latitudes were roughly in balance. In the Polar Regions, the sun rays are slanting. They are spread on a larger area. Hence, places near the Equator receive more heat and are hotter. Because the equator is closer to the sun and sun's rays travel through more atmosphere at the equator and sun's energy is more spread out at the equator and sun's rays hit the earth's surface at a higher angle at the equator.Sunlight hits the Earth most directly at the Equator. The curve of the Earth means that sunlight is spread over a wider area the further you move from the Equator. Sunlight hits a smaller surface area at the Equator so heats up quickly compared to the poles.Only a small part of the solar energy reaches the outer layer of the earth's atmosphere. Nearly half of it is absorbed while passing through the atmosphere and the rest reaches the earth's surface. So, only 0.00000005% of sun's total energy is received by the earth.
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