The Sun releases an estimated 384.6 yotta watts (3.846×1026 watts) of energy in the form of light and other forms of radiation. We are able to survive on Earth because the energy is spread over the area of a sphere with a radius of approximately 93,000,000 miles.
At the upper reaches of our atmosphere, the energy density of solar radiation is approximately 1,368 W/m2 (watts per square meter). At the Earth’s surface, the energy density is reduced to approximately 1,000 W/m2 for a surface perpendicular to the Sun’s rays at sea level on a clear day.
Solar energy is harvested by capturing light for direct photovoltaic conversion into electricity, or as thermal energy (heat) water heating, space heating and other uses.
If all the sunlight energy striking the Earth’s surface in Texas alone could be converted to electricity, it would be up to 300 times the total power output of all the power plants in the world!
Total world electricity production was 20,261 TeraWatt hours (TWh) in 2008.
Power plant output in watts is: 20,261 TWh ÷ 365 days/year ÷ 24 hours/day = 2.31 TW
Texas is 696,241 km2, so, 1,000 w/m2 x 1,000,000 m2/km2 x 696,241 km2 = 696,241,000,000,000 Watts = 696.241 TW
So, the sunlight falling on Texas at noon is equivalent to 696 TW solar energy ÷ 2.31 TW power plant output = 301 times the output of power plants.