For close to 50 years, energy futurists have touted solar energy straight from the source: space-based, sun-focused solar panels beaming electricity back to earth. Why try to replicate the enormous temperatures that power the fusion reactor that is our home star? How about fusion without the incredibly difficult terrestrial engineering challenges and no greenhouse gas emissions?
The U.S. space agency NASA lays out the allure of power directly from the sun: “Space-based solar power offers tantalizing possibilities for sustainable energy – in the future, orbital collection systems could harvest energy in space, and beam it wirelessly back to Earth. These systems could serve remote locations across the planet to supplement the terrestrial power transmission infrastructure required today.”
A massive Jan. 11 report from NASA then pours cold economic water on the hot topic of space-based solar power. The optimists about space-based solar overlook the costs in the glow of the enthusiasm, according to the report. In this respect, the advocates mimic the shortcomings other fans of far-off technologies such as earth-based fusion, magnetohydrodynamics, and coal gasification.
A NASA news release summarizes the 108-page report. Looking at two alternatives, NASA concluded that “space-based solar power would be more expensive than terrestrial sustainable alternatives, although those costs could fall if current capability gaps can be addressed. The report shows that emissions from space-based solar power could be similar to those from terrestrial alternative power sources but it noted that this issue requires more detailed assessments.”
“We found that these space-based solar power designs are expensive. They are 12 to 80 times more expensive than if you were going to have renewable energy on the ground.” — NASA official Erica Rodgers
Space News reported that NASA official Erica Rodgers said at the unveiling of the report, “We found that these space-based solar power designs are expensive. They are 12 to 80 times more expensive than if you were going to have renewable energy on the ground.” One of the alternatives NASA examined would produce delivered electricity at $0.61 per kilowatt hour, the other at $1.59/kWh. Terrestrial solar, wind, and hydro produce power at $0.02-$0.05/kWh.
What accounts for the enormous discrepancy? The costs on the ground are forbidding. According to NASA, “launch and manufacturing costs would need to be addressed – moving all that mass into orbit would require many sustained missions to carry infrastructure into space,” accounting for 70% of the costs of both alternatives.
Once in space, additional cost items would accrue. NASA noted, “Researchers would need to find ways to assemble and maintain large systems in orbit, enable those systems to operate autonomously, and develop efficient power-beaming to bring the harvested energy to Earth. These systems may need to operate in geostationary orbit, higher than the low-Earth orbit paths used by many of today’s satellites, which would carry additional challenges.”
Nonetheless, space solar visionaries are spinning the NASA report as positive. Writing in Space News, former NASA official David Steitz offered a positive spin on the new report. “The new NASA report,” he wrote, “withheld for more than a year for technical and political review, shows that there appear to be no clear technical showstoppers for an in-space solar power demonstration mission. It also showed that tapping into technologies under development today by NASA’s global partners could make space solar power beaming feasible soon — within two decades. And because pieces of this promising technology are currently or soon to be available, development requires no miracles — just commitment.”
Steitz called for the White House to take the lead in persuading Congress to authorize $50 million for the Pentagon’s “Defense Advanced Research Projects Agency” (DARPA) to launch a 5-kW demonstration program by 2028.
What are the odds of that? Slim and none, and Slim just walked off the launch pad.
–Kennedy Maize