If all goes well, Planet Earth may at some point be receiving solar power made in space under California Institute of Technology's (Caltech) Space-based Solar Power Project (SSPP). It would just make it possible for Earth to receive solar power even during night time, without the need for expensive energy storage, if one reaches that far.
That's just the idea behind the project that's already at an advanced stage of research with a test launch of multifunctional technology-demonstrator prototype due in early 2023.
According to Caltech, the idea is to collect solar power in space and transmit it wirelessly to Earth through microwaves 'unaffected by weather or time of day' so that solar power can be continuously available anywhere on earth.
To realize this, the research team plans to work on the concept of modular assembly of ultralight, foldable, 2D integrated elements as they believe integration of solar power and radio frequency (RF) conversion in 1 element avoids the need to have a power distribution network, doing away with weight and complexity of the project. It can be easily scaled up as well, as per Caltech.
"This ambitious project is a transformative approach to large-scale solar energy harvesting for the Earth that overcomes this intermittency and the need for energy storage, since sunlight shines continuously in space," says Harry A. Atwater, who is an SSPP researcher, Otis Booth Leadership chair of the Division of Engineering and Applied Science and the Howard Hughes professor of Applied Physics and Materials Science, and director of the Liquid Sunlight Alliance.
The project has reached this stage with the help of $100 million donation for the SSPP by lifetime member of Caltech Board of Trustees and Chairman of Irvine Company Donald Bren who also suggested the idea to CalTech. He initially shared the idea and made the donation anonymously in 2013, informed the institute. It was clarified that Bren will not hold any financial stake in the project, nor benefit from any technology created under SSPP.
However, the idea of space-based solar power generation has been around for many years – and in the meantime several terrestrial utility-scale solar projects offer solar power in the 1 US cents per kWh range with costs continuing to improve. Beyond cost, time is running out to fight climate change – the next 10-15 years are crucial, which also speaks for today's solar technology, which is not only the lowest cost power generation technology on earth but also the most versatile power generation technology.