|Click for gallery: Get a step-by-step look at how a space-based solar power system might work.
Power-beaming systems are moving from drawing boards and computer slideshow presentations to actual demonstrations on tabletops and in exhibit halls. But what will it take to turn power beams into profitable outer-space ventures?
Strangely enough, the challenge of constructing a sheet of thin-film solar cells that unfolds to a width of 1,000 feet (300 meters) in orbit is not the issue uppermost in the mind of William Maness, chief executive officer of Everett, Wash.-based PowerSat Corp. The problems that lead his list have more to do with earthly affairs - such as getting investors, utilities and regulators to buy into the idea.
Maness told a small gathering at a National Space Society meeting in Seattle this week that the pitch for space solar power has been directed too often at space enthusiasts who don't have a financial stake in the issue, rather than energy utility executives who do.
"This is one of the reasons why this concept has taken so long to start to catch on," he said.
Maness favors a more market-centered approach to the issue, and there are signs that the approach is taking hold. But other signs show why the challenge facing Maness and his colleagues in the space-power business is so daunting.
The Solaren story
First, the positive side: Maness pointed to Solaren Corp.'s deal with San Francisco-based Pacific Gas & Eelectric for a 200-megawatt space solar power pilot project as a potential success story. "That was some brilliant work," he said.
The deal still must pass regulatory muster, however, beginning with approval by California's Public Utilities Commission. Cal Boerman, Solaren's director for energy services, told me today that he expected the commission to make its decision in October or November. The company is also continuing its talks with potential launch providers such as United Launch Alliance, Boerman said.
Solaren's plan calls for sending power-generating satellites, or powersats, into space on four Atlas 5 heavy-lift rockets. The satellites would convert solar electric power into microwave energy for beaming down to a ground station, based within a mile or so of the existing power grid. Proximity to the grid is key, Boerman said: Neither PG&E nor the PUC wants to put in miles and miles of new high-voltage electrical lines to make use of solar-generated power.
The scheme would have to gain approval from the Federal Aviation Administration (because of the commercial launches) and the Federal Communications Commission (because each powersat is essentially a big telecommunication satellite), as well as from all the regulatory agencies who have a say in how the ground power station is built. Then Solaren would have to put the system into operation by 2016, or risk penalties prescribed by its PG&E contract.
Some say the Solaren deal is a "scam ... pure and simple." One scenario suggests that PG&E pursued the deal because it's a no-risk way to line up an excuse for falling short of California's renewable energy standards ("Gee, we tried our best, but our suppliers just couldn't follow through on their promises"). Maness, however, thinks that Solaren has displayed enviable business savvy so far. He counts the company as a rival to be respected.
Cost vs. benefit
Maness' vision for PowerSat would go far beyond Solaren's pilot project to put 300 powersats into orbit, forming a constellation capable of generating 2,500 megawatts of power. That would be an impressive resource, equal to more than a third of Grand Coulee Dam's electrical output. The only problem is, right now the project's numbers don't add up.
|PowerSat Corp. CEO William Maness
To be competitive with other power sources, Maness figures that the powersat system's launch costs would have to be around $100 per pound - which is roughly one-hundredth of the current asking price. Launch costs may be heading downward, thanks in part to the rise of SpaceX's Falcon rockets, but Maness can't yet predict when the charts tracing cost and benefit will cross into the profitable zone.
For now, Maness is targeting the 2017-2018 time frame for a space demonstration project. In the meantime, he's hoping to work through a tangle of regulatory issues and also keep an eye on his potential competitors - including not only Solaren but also Space Energy Inc., Space Island Group and Welsom Space Consortium.
"It's a race for us right now," Maness said.
Demonstrations in the works
Just in the past month there was quite a buzz over reports that Japanese companies were planning to join a $21 billion effort to set up a powersat system - but it's now clear that those reports were overblown.
The near-term investment is more on the order of $2 million for a demonstration of power-beaming technology, Maness said. If the technology works successfully in Earth-based tryouts, the Japanese plan to launch a test powersat in 2015. But a 1,000-megawatt space generating system of the sort mentioned in the initial reports is probably two decades down the road.
Japanese researchers have already made progress in the Earth-based demonstration phase: During a powersat symposium conducted this month in Toronto, Kobe University researcher Nobuyuki Kaya and his colleagues demonstrated an antenna system that could beam enough microwave energy across a 30-foot (10-meter) exhibit hall to power a small rover.
Alan Boyle / msnbc.com
PowerSat CEO William Maness' wireless power demonstrator lights up tiny LED
lights, just to show it's possible to beam electrical power through the air safely.
Maness has his own earthly demonstrations in the works: At the Seattle talk, he showed off a wireless power generator the size of a breadbox that transmitted enough power (5 watts) to light up LED lights about a foot away. And he has grander plans for building a demonstration power beamer mounted on a 20-foot truck, capable of transmitting 10 kilowatts over a distance of about 300 yards (meters).
The clock is ticking, however - not only for the powersat market but for other energy alternatives as well.
Terrestrial solar power may have its drawbacks. In addition to potential environmental concerns, large-scale solar farms can't generate a steady flow of electricity at night, or during cloudy weather. But if engineers ever figure out a way to store up the intermittent energy generated by solar cells or wind turbines, at levels high enough to keep utilities flush with power, Maness thinks that would deal a heavy blow to his powersat dreams.
"At that point, I take my marbles and go home," he said.
What do you think? Is space solar power little more than a sci-fi dream - at least until the space elevator is built? Or is it an idea whose time is about to come? Feel free to leave your comments below.
An earlier version of this report mischaracterized Space Canada as a potential PowerSat competitor rather than a nonprofit organization to promote powersats.