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Aug 27, 2009 | 28
Here's a seemingly simple solar power fact*: the sun bathes Earth with enough energy in one hour (4.3 x 1020 joules) to more than fill all of humanity's present energy use in a year (4.1 x 1020 joules). So how to convert it? In the world of solar energy harvesting, there's a constant battle between cost and efficiency. On the one hand, complex and expensive triple-junction photovoltaic cells can turn more than 40 percent of the (specially concentrated) sunlight that falls on them into electricity. On the other, cheap, plastic solar cells under development convert less than 5 percent.
In between, ubiquitous photovoltaics—the multicrystalline silicon solar panels cropping up on rooftops across the country and, indeed, the world—struggle to balance the need for (relatively) easy manufacturing and low cost with technology to get the most electrons for your solar buck.
Mar 15, 2009 | 2
Space shuttle Discovery reached orbit 200 miles above earth tonight at 7:51 local time, after taking off from Kennedy Space Center in Cape Canaveral, Florida at 7:43:44.
The shuttle will drop off the final pieces of the International Space Station's (ISS) solar arrays, and parts for its urine recycling system that would expand the ISS’s capacity from three to six crew members.
The launch was pushed back twice, first on February 4 when NASA said it needed more time to make sure that the valves controlling the flow of hydrogen gas into the external fuel tank do not pose a hazard. Engineers discovered that one of those valves had been damaged when another shuttle, Endeavour, lifted off in November.
Feb 4, 2009 | 3
It was a banner year for wind-energy in 2008, with the U.S. installing enough wind turbines to power two million homes and surpassing Germany to become the country with the most capability of generating power from wind. But can the U.S. remain in the lead in the midst of the recession?
A report released Monday by two wind-power advocacy organizations—the Brussels-based Global Wind Energy Council (GWEC) and Washington, D.C.'s American Wind Energy Association (AWEA)—showed that the U.S. doubled its capacity to create wind power last year. Meanwhile, a clean-energy analyst at investment bank Jeffries & Co., Michael McNamara, told Reuters that the U.S. will become the world's top solar producer this year. (Update [Feb. 6]: McNamara tells us today that the statement attributed to him wasn't quite right. "The U.S. will likely be the biggest producer of solar power in the future," he said.) More than 1,000 megawatts in solar power capacity were installed in the U.S. last year, says Monique Hanis, a spokesperson for the Solar Energy Industries Association (SEIA).
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