Imagine if, instead of covering suburban roofs and swathes of desert with solar panels, we could just send on big one up into space, to collect energy from the sun and send it back to us.
This faintly science fiction-y idea is exactly what space research groups all over the world are trying to do – and, amazingly, thanks to the work of two Japanese research groups, it might actually be within reach.
Japanese firm Mitusbishi and JAXA, the country’s space program, announced this month that they’ve succeeded in sending power collected from solar panels wirelessly to a receiver using microwave beams. This is a major breakthrough: the trickiest part of collecting energy on satellites 36,000km above earth is getting it back down again so we can use it for things like laptops and lawnmowers. If it works, space-based solar technology could collect energy at any time of day, and in any weather, making it far more efficient than solar panels on earth.
This diagram from JAXA gives a rough idea of how the technology would work. Orbiting solar panels attached to a geostationary satellite (one which always hovers above the same point on earth) and collect the sun’s energy. They then convert it into microwaves and beamed to solar receivers on farmland. This energy is then sent into grid.
