Solar Power Satellites could broadcast energy to Earth
October 29, 2008 Another year of rising oil prices and global warming, another scientist blows the dust off an old renewable energy proposal. Ben Bova, president of the National Space Society, recently published an article in The Washington Post strongly recommending that the next president of the United States commission a US$1 billion solar power satellite from NASA before the end of their second term. The satellite would harness energy directly from the sun and broadcast it back to a receiver on Earth using microwave frequencies.
The theory of wireless power was conceptualized in the late 19th century, but it was all formulas and small-scale lab experiments until Nicola Tesla came along and built the 187-foot high Wardenclyffe Tower. The Tower, which was specially designed to facilitate wireless power and communication, “[had] a grip on the earth so the whole of this globe can quiver” – (those are Tesla’s words; the man barely restrained himself from adding “…you fools!” to the end of every hypothesis). Unfortunately, the popular press didn’t quite share his enthusiasm, and instead dubbed the scheme “Tesla's million-dollar folly." Wardenclyffe Tower was never fully operational, and was destroyed in WWI. However, Tesla did demonstrate the viability of wirelessly transmitting and receiving electricity, and successfully scored patents on many of its applications.
In 1968, the Space Race caused the wireless energy concept to be re-imagined as a means to turn solar energy into electricity and beam it down to Earth. In 1973, Peter Glaser was granted a patent for his power broadcasting system, which involved using a one-square kilometer antenna on a satellite to broadcast power via microwaves to a larger receiver on the ground. The solar power satellite proposal was then kicked around by NASA and the Department of Energy for a few decades, with various feasibility reports usually stating that the technological principles were sound, but the cost was too steep. In his recent Washington Post article, Ben Bova argues that the cost/benefit equation of satellite-beamed power has finally tipped enough to make the SPS actionable. The benefits of the solar power satellite are that once it’s up there, it delivers a constant stream of power to Earth, garnered from an unlimited source. Unlike solar panels here on the ground, its performance is not affected by the weather – and unlike nuclear power and fossil fuels, it produces no waste, and uses a renewable resource. Bova’s proposal involves the construction of a demonstration-model solar power satellite that produces 10 to 100 megawatts. It won’t power much, but it will be the important first step, the proof-of-concept prototype that engages the private sector and encourages government investment. A full, mile-long model, according to Bova, would produce five to ten gigawatts of energy – more than enough for California’s 4.4-gigawatt appetite.
Just the act of building the first one, says Bova, would be enough to jump-start the world into wide-scale development. It may sound overly optimistic, but governments are already investing tens of billions of dollars in nuclear power. If SPS demonstrates a cost-effective yield, then countries already considering it, like Japan, might hasten their development. It seems strange that an idea that has existed for 40 years, which uses century-old scientific theory and existing technology, which alleviates an environmental problem we have known about for decades, and eases the increasing political and financial burden of the fossil fuel economy, has been repeatedly put on ice because of a cost that is still a fraction of what governments spend on military aims. When the idea was first shot down, and Tesla came to grips with losing Wardenclyffe Tower, he stated (in a long rant, but one worth reading):
"It is not a dream, it is a simple feat of scientific electrical engineering, only expensive — blind, faint-hearted, doubting world!...Perhaps it is better in this present world of ours that a revolutionary idea or invention instead of being helped and patted, be hampered and ill-treated in its adolescence — by want of means, by selfish interest, pedantry, stupidity and ignorance; that it be attacked and stifled; that it pass through bitter trials and tribulations, through the strife of commercial existence. So do we get our light. So all that was great in the past was ridiculed, condemned, combatted, suppressed — only to emerge all the more powerfully, all the more triumphantly from the struggle."
After more than a century, it’s possible that Tesla’s wireless power will finally emerge. And if the next US President does take Bova's advice, it's possible that it will combat our energy problems, and environmental problems, at the same time.