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A Less Well-Oiled War Machine

The high cost of petroleum is forcing the U.S. military to turn to solar, geothermal, and wind energy

13 min read
14-megawatt photovoltaic array
Fertile Land: The U.S. military is using some of its vast quantities of land to generate power, as it did for this 270-megawatt geothermal power plant and a 14-megawatt photovoltaic array (above), both located in the Mojave desert.
Photo: MMA Renewable Ventures

In the middle of the Mojave Desert, a nondescript two-story building behind a gated fence houses an unlikely group of geologists. Their lineage is strong: several generations of prospectors have been drawn to dig in this dry corner. Within 100 kilometers of the geologists’ base near China Lake, Calif., 19th-century gold diggers stumbled on riches, and later oilmen got lucky in the same inhospitable soil. Now these earth-minded fellows have grand ambitions of their own. Their aim is to turn the U.S. Department of Defense into one of the world’s largest users of geothermal energy.

Their vision isn’t all a pipe dream. The rising cost of fuel has the Pentagon pressuring the four branches of the armed services to cut their energy bills wherever they can. It’s easy to see why—every US $10 increase in the price of a barrel of oil costs the Air Force, for example, an extra $600 million. The Army, Navy, and Marines, too, are tearing through their budgets. In response, energy managers at bases across the country are reevaluating how they light, insulate, heat, and cool their buildings. The most ambitious of these managers have begun aggressively adopting renewable-energy technologies. Together they have emerged as a distributed network of clean-energy advocates. The irony, of course, is that these military men and women should form such a group at the heart of one of the most energy-intensive operations on the planet.

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Caltech Team Launches Experimental Space-Based Solar Array

The satellite will test some of the tech needed to wirelessly beam power from orbit

4 min read
A lightweight gold-colored square frame for a solar power array, seen flying in space with Earth in background.

Artist's conception of Caltech's Space Solar Power Demonstrator in Earth orbit.


For about as long as engineers have talked about beaming solar power to Earth from space, they’ve had to caution that it was an idea unlikely to become real anytime soon. Elaborate designs for orbiting solar farms have circulated for decades—but since photovoltaic cells were inefficient, any arrays would need to be the size of cities. The plans got no closer to space than the upper shelves of libraries.

That’s beginning to change. Right now, in a sun-synchronous orbit about 525 kilometers overhead, there is a small experimental satellite called the Space Solar Power Demonstrator One (SSPD-1 for short). It was designed and built by a team at the California Institute of Technology, funded by donations from the California real estate developer Donald Bren, and launched on 3 January—among 113 other small payloads—on a SpaceX Falcon 9 rocket.

“To the best of our knowledge, this would be the first demonstration of actual power transfer in space, of wireless power transfer,” says Ali Hajimiri, a professor of electrical engineering at Caltech and a codirector of the program behind SSPD-1, the Space Solar Power Project.

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Forecasting the Ice Loss of Greenland’s Glaciers With Viscoelastic Modeling

Researchers at the Alfred Wegener Institute in Germany are developing new models to simulate how glaciers behave

8 min read
Aerial view of Nioghalvfjerdsbræ showing the extensive patterns of the crevasses

This sponsored article is brought to you by COMSOL.

To someone standing near a glacier, it may seem as stable and permanent as anything on Earth can be. However, Earth’s great ice sheets are always moving and evolving. In recent decades, this ceaseless motion has accelerated. In fact, ice in polar regions is proving to be not just mobile, but alarmingly mortal.

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