‍What is happening?

UK-based start-up, Space Solar, has partnered with Iceland’s Transition Labs to deliver the first space-based solar power (SBSP) Reykjavik Energy by 2030. Space Solar’s inaugural SBSP plant is projected to generate 30 MW of continuous power, regardless of weather conditions or time of day. The partnership aligns with Reykjavik Energy’s commitment to sustainability, including its carbon storage subsidiary, Carbfix. Jointly, the firms are seeking sites for ground-based receiver stations, with Iceland, Canada and northern Japan as potential locations as the constellation of power stations develops towards the goal of achieving gigawatt-scale capacity by 2036. (Power Engineering International)

Why does this matter?

Global electricity demand is projected to double from 25,000 TWh in 2023 to between 52,000 and 71,000 TWh by 2050. Replacing fossil fuels with renewables to meet this rapid increase is critical to limiting global warming to 1.5C as outlined by the Paris Agreement. The race to net zero by 2050 has seen a surge in wind and solar capacity added to energy systems worldwide. However, more is needed and with current renewables being intermittent, energy security is critical. While Battery storage, hydrogen and nuclear are touted as green solutions, many countries are also investing in SBSP concepts.

How SBSP technology works

The technology for SBSP already exists and has been demonstrated by Caltech researchers, albeit on a pilot scale that will inform future development. However, to generate a viable power source, these satellites, which often feature a system of mirrors to reflect sunlight onto solar panels, need to be more than a kilometre across. They also need to be in geostationary orbit 36,000 km above the Earth where the sun is visible 99% of the time. Energy will be beamed from the satellites in the form of microwaves to net like receiving antennas, or “rectennas”, on Earth which convert it into direct current electricity. These will likely require several kilometres of space, although Space Solar suggests the area needed is just 8% of a wind farm generating a similar amount of power.  

Scaling up production, scaling down cost

Historically, SBSP has been deemed too expensive, but the cost of space launches has tumbled by 90% in recent years to less than $2,000 per kilogram, and prices continue to fall. Meanwhile, modular solar power satellite (SPS) designs, such as SPS Alpha and IECL’s CASSIOPeiA – which Space Solar holds exclusive rights – are notably lower in mass, reducing manufacturing costs while being more resilient to failures. Studies indicate that the resulting cost of SBSP would be in the region of £50 ($64) per MWh, competitive with renewables and far cheaper than nuclear.  

Production in process

Space Solar’s demonstration satellite will be approximately 400 metres wide, weighing 70.5 tonnes. It will orbit at altitudes of between 2,000 and 36,000 km. The firm aims to scale the system to a constellation of six satellites capable of delivering gigawatts of electricity by 2036. More than 15 GW could be generated by the mid-2040s. If successful, the project could catalyse further investment in SBSP technologies and related industries. It could also spur the development of international regulations and standards yet to be established.  

Ultimately, the CASSIOPeiA satellite will weigh 2,000 tonnes with a diameter of 1.7 km. Space Solar intends to utilise reusable heavy lift launchers currently in development, such as the Space X Starship and Blue Origin New Glenn to get the system off the ground. Once in orbit, the satellite will be assembled by advanced autonomous robots, which will also undertake maintenance. While it will take more than a decade before SBSP becomes a truly commercial possibility, it is an area well worth watching for its potential in helping to deliver the 100% clean energy mix needed by 2050.