It sounds like a plan concocted by a supervillain, if that villain’s baneful end was to provide cheap, clean energy around the world: launching a three-kilometer-wide array of solar panels that beam the sun’s energy to the surface. Even the price seems straight out of pop fiction: a hundred million dollars. But this is a real project at Caltech, funded for nearly a decade in large part by a single donor.
The Space-Based Solar Power Project has been underway since at least 2013, when the first donation arrived from Donald and Brigitte Bren. Donald Bren is the president of the Irvine Company and a member of the Caltech board of directors, and after hearing about the idea of space-based solar energy in Popular Science, he proposed funding a research project at the university, and has since donated more than $ 100 million. with the purpose. The source of the funds has remained anonymous until this week. when Caltech made it public.
The idea arises naturally from the current limitations of renewable energy. Solar energy is ubiquitous on the surface, but of course it is highly dependent on the weather, the season, and the time of day. No solar panel, even under ideal circumstances, can operate at full capacity all the time, so the problem becomes transferring and storing energy in a smart grid. Without solar panel on earth, that’s.
However, a solar panel in orbit can be exposed to all the sunlight almost all the time, and without the reduction of its power that comes from that light that passes through the protective atmosphere and the magnetosphere of the planet.
“This ambitious project is a transformative approach to large-scale solar energy harvesting for Earth that overcomes this intermittency and the need for energy storage,” said SSPP researcher Harry Atwater in the Caltech statement.
Of course, you would need to collect enough energy that it is worth doing in the first place, and you need a way to transmit that energy to the surface in a way that does not lose most of it in the aforementioned protective layers, but also does not fry anything. let it pass your way.
These fundamental questions have been systematically analyzed over the past decade, and it is clear to the team that without Bren’s support, this project would not have been possible. Trying to get the job done while looking for scholarships and rotating through graduate students might have prevented it from getting done, but constant funding meant they could hire long-term researchers and overcome early hurdles that might have otherwise hindered them.
The group has produced dozens of published studies and prototypes (which you can peruse here), including the lightest solar collector-transmitter ever made by an order of magnitude, and is now about to launch its first space test satellite.
“[Launch] it is currently expected to be the first quarter of 2023, ”project co-director Ali Hajimiri told TechCrunch. “It involves several demonstrators for spatial verification of key technologies involved in the effort, namely remote wireless power transfer, lightweight flexible photovoltaics, and deployable flexible space structures.”
These will be tests on a small scale (about 6 feet wide), but the vision is for something much larger. Larger than anything currently in space, in fact.
“The final system is envisioned to consist of multiple modules deployable in close formation flight and operating in sync with each other,” Hajimiri said. “Each module is several tens of meters on a side and the system can be built by adding more modules over time.”
Eventually, the concept requires a structure perhaps as large as 5-6 kilometers wide. Don’t worry, you would be far enough away from Earth not to see a giant hexagon blocking out the stars. The energy would be sent to the receivers on the surface by directed and steerable microwave transmission. Some of these in orbit could transmit energy to any place on the planet full time.
Of course, that is the vision, which will take many, many years, if it is to come to pass. But do not make the mistake of thinking that this has that one ambitious goal, you could even say great. The pursuit of this idea has produced advances in Solar cells, flexible spatial structures, and wireless power transfer, each of which can be applied in other areas. Vision may be the stuff of science fiction, but science is progressing in a very informed way.
For his part, Bren appears to be happy just getting the ball forward in what he considers to be an important task that otherwise would not have been attempted at all.
“I have been a student investigating the possible applications of space-based solar energy for many years,” he told Caltech. “My interest in supporting world-class scientists at Caltech is driven by my belief in harnessing the natural power of the sun for the benefit of all.”
We will check back with the SSPP before launch.