JAXA researchers are planning on putting a prototype of the system in geosynchronous orbit approximately 36,000 km above the equator. A laser beam will be used to transfer the energy collected by the space-based solar panels to an intermediary or terrestrial power station, where its energy will be used to generate electricity or hydrogen. The Japanese scientists are using solar plates made from chromium, a ceramic material that absorbs the sunlight, and neodymium, which converts it into laser light. These solar panels demonstrated a 42% solar-to-laser energy conversion efficiency – an impressive figure that outperforms previous technology by a factor of four.
Since this innovative system will be situated in space, it will be able to collect sunlight 24 hours a day, circumventing problems affecting ground-based solar energy systems, such as cloudy skies and darkness. The Sun’s energy is eight times greater outside Earth’s atmosphere. Therefore, it is estimated that a single satellite-mounted solar panel site will have a power output equivalent to a 1 GW nuclear power plant.
While scientists continue to further explore the idea, some suggest that these power plants be put in low Earth orbit first, and only then be launched into a higher geosynchronous orbit or to an orbit around the Moon. The Japanese researchers, who introduced their technology at a meeting of the Japan Society of Applied Physics this year, are hoping to place the first space-based power systems in orbit by the year 2030.
The idea of turning to space for power isn’t new. In the 1970’s, NASA and the U.S. Department of Energy conducted several studies regarding the design of extraterrestrial solar power satellites, but abandoned the idea due to the extremely high cost of such projects. Even earlier, already five decades ago, this concept was mentioned by Physicist Freeman Dyson. Dyson, mentioned in TFOT as one of the fathers of the original Orion nuclear space propulsion concept that was recently “updated” by Andrews Space & Technology, speculated that advanced civilizations would build rings of “solar collectors” around their suns to capture energy these gigantic constructions now know as “Dyson spheres” could potentially be detected by powerful telescopes as Dyson himself suggested in a 1959 paper published in the magazine Science .