Concept Powering The "World" With A Solar Satellite

Space-based solar power (SBSP), or historically space solar power (SSP) is a system for the collection of solar power in space, for use on Earth. SBSP differs from the usual method of solar power collection in that the solar panels used to collect the energy would reside on a satellite in orbit, often referred to as a solar power satellite (SPS), rather than on Earth's surface. In space, collection of the Sun's energy is unaffected by the various obstructions which reduce efficiency or capacities of Earth surface solar power collection.

The World Radiation Centre's 1985 standard extraterrestrial level for mean solar irradiance at one astronomical unit from the Sun is 1367 W/m². The integrated total terrestrial solar irradiance is 950 W/m². Extraterrestrial solar irradiance is thus 144% of the maximum terrestrial irradiance, and has a different radiation profile, including wavelengths blocked by the atmosphere. A major interest in SBSP stems from the length of time the solar collection panels can be exposed to a consistently high amount of solar radiation. For most of the year, a satellite-based solar panel can collect power 24 hours per day, whereas a terrestrial station can collect for at most 12 hours per day, unless at the poles, but then only for 6 months of the year, if weather permits, and only during peak hours—irradiance under the best of conditions is quite reduced near sunset and sunrise.

The conceiver of one of mankind's coolest ideas for boundless clean energy died last week. He was 90 and first published his ideas in 1968, a year before NASA put a man on the moon. In its December 1972 issue, Popular Science described engineer Peter Glaser's proposal:

Glaser's plan is to build a huge array of solar cells in a synchronous orbit around Earth to collect sunlight, convert it into DC electric power. The DC could be used to power microwave convertors, and the microwave energy would be beamed to Earth, where it would be received by a large antenna and converted back into electrical power.

Although it sounds incredible, the basic technology for Glaser's orbit-to-Earth power plant already existed at the time. However, nobody had used the tech in that large of a project before. In addition, it would take an enormous amount of money and resources to make such a plant happen, including about 500 shuttle flights to bring all of those components to space, Glaser estimated.

The U.S. government studied the plan at a cost of $20 million, The New York Times reports. Ultimately, researchers decided it was too infeasible.

Although Glaser's proposal never made it to reality, former Popular Science editor-in-chief Hubert Luckett credited the idea for sparking research into Earth-bound solar energy fields more akin to what we have today. The magazine published a feature on the future of solar energy in its December 1972 issue. In addition to Glaser's ideas, writer C. P. Gilmore described a more familiar-sounding vision:

The [Aden and Marjorie] Meinel plan is simple in principle, breathtaking in scope. They hope ultimately to build a vast array of 'solar farms' across the southwestern deserts that will collect heat, use it to generate steam and run power-generating turbines. They envision a long-range plan to create a 1,000,000 megawatt generating facility . . . .

That sounds a lot like the Ivanpah Solar Electric Generating System in California, does it not? One major difference is that Ivanpah makes 392 megawatts of gross power (377 megawatts net), not, uhh, 1 million megawatts. (The Meinels, who worked primarily as astronomers, never went much further with their idea and were not involved in Ivanpah's design and construction.)

"Things have never looked better" for solar energy research, Glaser told Popular Science, in that issue.

Solar energy research passed several milestones in the 1970s, including increases in the efficiency of solar cells and the construction of one of the world's first solar-powered residences by researchers at the University of Delware.