The concept of harvesting some of the unlimited sunlight available in space, then beaming it down to consumers, was first developed to serve the clean energy needs of planet Earth. But space solar might work for the moon, too.
As part of the ESA Open Space Innovation Platform campaign on “Clean energy – new ideas for solar energy from space”, a study done by Switzerland Astrostrom company designs lunar power plant Greater Earth, or GE⊕-LPS in short.
The study envisions a solar power satellite constructed primarily from lunar resources (including solar cells manufactured on the Moon) that could deliver megawatts of microwave power to receivers on the lunar surface, serving the needs of surface activities, including future manned bases.
Drawing inspiration from a butterfly, the GE⊕-LPS features V-shaped solar panels with integrated antennas arranged in a spiral configuration spanning more than a square kilometer from end to end. The design will provide a continuous 23 megawatts of power for operations on the lunar surface. The solar panels themselves are based on single-layer iron pyrite solar cells produced on the moon.
Located at the Earth-Moon Lagrange point about 61,350 km from the lunar surface, the station itself will also be inhabited. It will serve as a gateway between Earth and lunar operations, providing artificial gravity for adaptive health purposes to potentially become an attractive tourist destination in its own right – as well as a prototype for further space settlements in cislunar space.
This visionary study outlines a potential future for large-scale and greener satellite solar power production in the longer term if ESA’s SOLARIS R&D initiative confirms the feasibility of space-based solar power to serve Earth’s clean energy needs.
“Launching a large number of gigawatt solar power satellites into orbit from the Earth’s surface will face the problem of a lack of launch capacity as well as potentially significant atmospheric pollution,” explains Sanjay Vijendran, who leads SOLARIS. “But once a concept like GE⊕-LPS has proven the component manufacturing processes and the concept of assembling a solar power satellite in lunar orbit, it can be scaled up to produce additional solar power satellites from lunar resources to serve the Earth.”
Such Moon-built solar energy satellites would require about five times less velocity change to place them in geostationary Earth orbit than Earth-launched satellites.
Sanjay adds, “It would also create many other benefits in addition to providing enough clean energy for Earth, including the development of a cislunar transportation system, mining, processing and manufacturing facilities on the Moon and in orbit, leading to a two-planet economy and the birth of of a space civilization.
Investigating the technical and financial feasibility of the concept, the study found that GE⊕-LPS could be achieved without requiring technological breakthroughs. Most of the essential technologies for mining, beneficiation and manufacturing operations on the surface of the Moon are already in use or being developed on Earth today. These technologies can be extrapolated and adapted to the lunar environment, delivered in modular form, and operated telerobotically on the lunar surface.
Although significant engineering development would be required, the study found that solar power satellites built on the Moon would not only be cheaper than any comparable solar power satellite developed on Earth, but that the electricity generated for Earth, will also be cost-competitive with any terrestrial power alternative.
This OSIP talk is funded through ESA’s Discovery programme. For more information, see the details in the ESA Nebula study library.