The inventions that impound solar energy through sun‐reflecting or lensing devices are fascinating to the imagination but relatively insignificant in potential. In fact, they work only few hours daily when the sun is at a favorable angle.
Even if half of Arizona were turned into a direct‐sunlight‐energy‐converting mechanism, the production would be negligible in comparison with windpower sources.
Wind power is in a class by itself as the greatest terrestrial medium for harvesting, harnessing and conserving solar energy. The water and air waves circulating around our planet are unsurpassed energy accumulators whose captured energy may be used to generate electrical, pneumatic and hp draulic power systems.
Windmills produce power from the sun ‐ generated differentials of heat, which are the source of all wind, with far greater efficiency than do attempts to focus and store direct solar radiation. But the most comprehensive consideration regarding wind power is not technological. Rather it is an appreciation that wind ‘power is by far the most efficient way to recapture solar power.
In the first place, three‐quarters of the earth is covered with water, and the remaining quarter is land area consisting largely of desert, ice and mountains. Only about 10 per cent of our planet's area has terrain suitable to cultivation, in which vegetation can impound the sun's radiation by photo. synthesis.
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Among the solar‐energy impounders in vegetation, none can match corn's performance. Corn converts and stores as recoverable energy 25 per cent of the received ultraviolet radiation, whereas wheat and rice average only 18 to 20 per cent. From these stores of solar energy humans can produce commercial alcohol, or they can leave the energy to the production of fossil fuels in the earth's crust, which requires millennia.
But one‐half of the vegetation‐producing area of the earth's surface is always in the shadow, or night, side, which reduces to 5 per cent the working area of the earth's surface on which vegetation impounds the sun's energy. Though theoretically 5 per cent of the area can impound energy at any one time, only an average of one per cent of the sun's energy is actually being converted because of local weather conditions and infrared and other energy‐radiation interferences.
The area of the surface of a sphere is exactly four times the area of the sphere's great‐circle disk, as produced by a plane cutting through the center of the sphere. The surface of a hemisphere is, then, twice the area of the sphere's great‐circle plane. When we look at the “full” moon, we are looking at a surface twice the area of the seemingly flat, circular disk in the sky.
All of the earth's energy comes from the stars, but primarily from the star sun, as radiation or as inter‐astrogravitational pull. Twenty‐four hours a day the sun is drenching the outside of the hemisphere of the cloud‐islanded atmosphere's 100‐million‐squaremile surface area, which is twice that of the disk of the earth's profile.
This gives us one billion cubic miles on the sunny side and one billion cubic miles on the shadow side. The atmospheric mass is kinetically accelerated in the hemisphere constantly saturated by the sun, while simultaneously the atmospheric kinetics in the night hemisphere are decelerated.
All around the earth, yesterday's sun impoundments perturbate the atmosphere by thermal columns rising from the oceans and lands. The shadow side consists of one billion cubic miles of contracting atmosphere, while the one billion cubic miles on the sunny side is sum‐totally expanding. This rotation of the earth brings about myriad of high‐low atmospheric differentials and world‐around semi‐vacuumized drafts, which produce the terrestrial turbulence we speak of as the weather.
The combined two billion cubic miles of continual atmospheric kinetics converts the solar energy into wind power. Wind power is sun power at its greatest, by better than 99 to 1.
All biological life on planet earth regenerated by star energy, and overwhelmingly by the sun's radiation. The sun radiates omnidirectionally 92 million miles away from earth, with only two‐billionths of its total radiation impinging upon earth. The radiation arrives at a rate of two calories of energy per each square centimeter of earth's sun‐side hemispherical surface per each minute of time. About half of that is reflected back omnidirectionally to the universe. The other half, i.e., one calorie per minute per square centimeter, is impounded by our planet's biosphere in ways making them available to human use.
No matter how dubious one may be of such logical realizations of our potentials, the fact remains that our net receipt and impoundment of cosmic energy amounts to 168 quintillion horsepower a minute, which can also be stated as 125 quintillion kilowatts a minute, which, with 525,600 minutes a year amounts to 66 septillion kilowatts a year. This is 66 x 1024 kilowatts, eleven ‐ billionfold the world's present 5 x 106 kilowatt production of electric‐energy power.
If ‘all humanity enjoyed 1973's “highest” living standards—that of the United States—each human on earth would consume 200,000 (2 x 105) calories day.
Assuming five billion (5 x 107) humans by A.D. 2000, each consuming 2 x 105 calories daily, we will need 1 x 1015 calories a day, while our actual daily terrestrial income of cosmic energy is 72 x 1020 calories.
Our planet's usable daily energy income is therefore 72 x 105, or seven millionfold our daily requirements of A.D. 2000.
R. Buckminster Fuller
This article first appear on NY Times Archives