Plugging Into the Sun  

National Geographic's cover story this month (for readers outside the US) is on solar energy (particularly solar thermal power and thin film solar), noting "Sunlight bathes us in far more energy than we could ever need—if we could just catch enough" - Plugging Into the Sun. A related article is - Can Solar Save Us ? - with a photo gallery at - Solar Rays.

When Nevada Solar One came on line in 2007, it was the first large solar plant to be built in the United States in more than 17 years. During that time, solar technology blossomed elsewhere. Nevada Solar One belongs to Acciona, a Spanish company that generates electricity here and sells it to NV Energy, the regional utility. The mirrors were made in Germany.

Putting on hard hats and dark glasses, Cable and I get into his pickup and drive slowly past row after row of mirrors. Men with a water truck are hosing down some. "Any kind of dust affects them," Cable says. At the far edge of the mirror field, we stop and step out of the truck for a closer look. To show how sturdy the glass is, Cable bangs it like a drum. Above his head, at the focal point of the parabola, the pipe carrying the oil is coated with black ceramic to soak up the light, and it's encased in an airless glass cylinder for insulation. On a clear summer day with the sun directly overhead, Nevada Solar One can convert about 21 percent of the sun's rays into electricity. Gas plants are more efficient, but this fuel is free. And it doesn't emit planet-warming carbon dioxide. ...

With a new administration in Washington promising to take on global warming and loosen the grip of foreign oil, solar energy finally may be coming of age. Last year oil prices spiked to more than $140 a barrel before plunging along with the economy—a reminder of the dangers of tying the future to something as unpredictable as oil. Washington, confronting the worst recession since the 1930s, is underwriting massive projects to overhaul the country's infrastructure, including its energy supply. In his inaugural address President Barack Obama promised to "harness the sun and the winds and the soil to fuel our cars and run our factories." His 2010 budget called for doubling the country's renewable energy capacity in three years. Wind turbines and biofuels will be important contributors. But no form of energy is more abundant than the sun.

WHEN Lindsay Tanner says greenies are ''obsessed'' with solar energy, he's right. And it's obvious why.

Clean coal is a myth. Nuclear has radioactive waste and security issues and (read Helen Caldicott) it's not as efficient as they say. It would also be impossible to commission a nuclear reactor in Australia within a decade - especially near anyone's backyard - and we haven't got a decade to lose. ...

Solar technology has been around for decades, the resource is abundant and the costs are coming down.

How abundant? This month's National Geographic cover story on solar power estimated that the amount of electricity that could be generated by solar photovoltaics (PV) and concentrating solar thermal (CSP) each year was roughly 40 times the world's present electricity use. (In round figures, 745,000 terawatt hours a year of solar power is available, and the world generated 19,000 terawatt hours in 2006, mostly from fossil fuels).

But the promise of solar has been around so long people don't believe it any more. NG's reporter quoted from a magazine article published in America in 1953, titled Why Don't We Have … Sun Power? That old piece included this: ''Every hour the sun floods the earth with a deluge of thermal energy equal to 21 billion tons of coal.''

Adelaide-based scientist Monica Oliphant is president of the International Solar Energy Society. She has been a staunch advocate for solar power since the Arab conflict and oil shock in the early 1970s, when she heard Nobel-prize winning Australian virologist Sir Macfarlane Burnet on the radio.

''I remember the day - I was in the kitchen, [he] was saying: 'If we had solar energy we wouldn't have to fight over oil.' ''