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I first heard about space-based solar power (SBSP) when I worked with a gentleman named John Mankins back when I was doing consulting work for the Department of Energy. A former NASA employee, he is now CTO of Managed Energy Technologies, and was recently featured on the Discovery Channel for his work furthering wireless power transmission - a crucial element of SBSP. Like other proponents of SBSP, John was frustrated that the concept wasn’t receiving more attention.

Well, SBSP has been getting a lot of attention this week after California utility Pacific Gas & Electric requested regulatory permission to enter an agreement with Solaren to deploy a SBSP solution.  The project, if approved, would set out to beam 200 MW of solar power to earth from space.

So why look to space? Not only does the sun shine 24×7, it shines at a much stronger intensity (or insolation) - if it could be captured and transmitted back to earth, we’d have more energy than we could use. A 2007 Pentagon report that examined the topic put it this way:

“A single kilometer‐wide band of geosynchronous earth orbit experiences enough solar flux in one year (approximately 212 terawatt‐years) to nearly equal the amount of energy contained within all known recoverable conventional oil reserves on Earth today (approximately 250 TW‐yrs). The enormous potential of this resource demands an examination of mankind’s ability to successfully capture and utilize this energy within the context of today’s technology, economic, and policy realities, as well as the expected environment within the next 25 years. Study of space‐based solar power (SBSP) indicates that there is enormous potential for energy security, economic development, advancement of general space faring, improved environmental stewardship, and overall national security for those nations who construct and possess such a capability.”

But is SBSP feasible?

Like all emerging technologies, the main question is, what does it cost? Simply, A LOT. The aforementioned Pentagon report concluded, as noted in the WSJ, that a $10 billion would be needed to have a 10 MW pilot satellite in orbit by 2016. That’s a cost of $1 million per kW! That’s about 140 times the cost per kW of the next most expensive carbon-free technology, nuclear. Even launching such satellites would be a challenge. The aforementioned Pentagon report also stated that “existing launch infrastructure cannot close the business case.”

Even if the costs could be reduced and the launch infrastructure improved, the power would still need to be transferred back to earth, wirelessly. And while Mankins set a new record, beaming power wirelessly 92 miles between Hawaiian islands, no one has tried to wirelessly transmit power in large amounts or over thousands of miles. Solaren, however, appears to be confident in their approach. In an interview on PG&E’s blog, Solaren CEO Gary Spirnak said, “While a system of this scale and exact configuration has not been built, the underlying technology is very mature and is based on communications satellite technology. For over 45 years, satellites have collected solar energy in earth orbit via solar cells, and converted it to radio frequency (RF) energy for transmissions to earth receive stations. This is the same energy conversion process Solaren uses for its SSP plant.”

While PG&E will likely be criticized for examining such a costly solution, I think the utility should actually be lauded to looking for long-term, game-changing approaches to our energy challenge. The case can certainly be made that such a disruptive technology should be developed through an Apollo-like program, but the government isn’t launching one. Perhaps that’s why the private-sector, though startups like Solaren and Space Energy (and the VCs that back them), are taking the challenge on themselves.

This reality leads to a challenging situation  - utilities, and the regulators that oversee them, are supposed to procure the most cost-effective power for their customers - and SBSP likely doesn’t meet that test.