The Sun delivers energy to the 200 million square miles of Earth's surface, that is thousands of times greater than we humans generate from all sources. The quantity is so huge that solar seems to be the answer to the coming energy crisis. However, it is spread too thin for use; like collecting barrels of oil from an oil slick on water. See coming posts for reasons.
This does not say we don't use solar energy. Along with heat from radioactivity in the Earth, solar keeps ground level temperature about 300-degrees C above absolute zero; distills and distributes water worldwide; drives the winds, and thermohaline ocean circulation to moderate air temperatures in all latitudes; and energizes plant life to provide food and forest products for humans and animals. We should be contented with this.
50% of solar energy reaches the ground. Currently a tiny bit is accessed by photovoltaic cells to give 0.066Q of the total 100Q (eia.doe.gov) that America generates from all sources. Note: this amount is only 2/3 of 1/10 of one percent of the 100Q .
The Sun delivers 175 petawatts (10 x 10 to 15th watts) to the disc of Earth every instant; by 8060 hours, this is 1500 petakilowatt-hours (PKWH) per year. Since 50% reaches ground, and the US is 1.5% of the world's land, we get 11 PKWH per year, versus 100Q (BTU).
One kilowatt-hour equals 3412 BTU (Google), so our 11 PKWH equals 3.7 times 10 to 18th BTU. Divided by our 100Q BTU (10 times 10 to 14th), solar is 3700 times as much as the energy we generate. All other nations (28.5% of Earth's land) get 19 times as much solar energy, but make only three times as much energy, 300Q. Their solar-to-human energy multiple is 6.5 times as much as ours, or 24,000.
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