Orbiting Space Power Systems Would Convert Sunlight into Laser Beams
While the rest of the world (save for the Indians) has been busy focusing on mainly terrestrial-based solar energy alternatives, the Japanese have been looking to the heavens to find a potential solution. Scientists from the Institute of Laser Engineering at Osaka University and the Japan Aerospace Exploration Agency (JAXA) have just developed a new technology for converting sunlight into laser beams — a technology that could form the basis for JAXA's Space Solar Power Systems (SSPS) project.
The SSPS project seeks to put a prototype space-based power system in orbit — 22,400 mi (36,000 km) above the equator — with the goal of harnessing the sun's energy to produce laser beams that would generate electricity or hydrogen on Earth through the intermediary of a terrestrial power station. The lasers — using plates built from a ceramic material containing chromium, which can absorb sunlight, and neodymium, which converts it into laser beams — outperformed earlier technologies four times over, demonstrating a solar-to-laser energy conversion efficiency of 42%.
The main advantage of using space-based power systems over terrestrial ones is that the former will not be subject to cloudy conditions or nighttime darkness, allowing them to collect solar energy 24 hours a day. The researchers estimate that a single satellite-mounted power system could generate as much energy as a 1-GW nuclear power plant by the time they send the first one into orbit in the next few decades.