Orbital solar power plants: the new innovation in clean energy production?

The concept of a solar power plant is not new, in fact we have to go back to the end of the 1960s to see the first representation. At the time, the objective was to provide access to clean energy, especially in the context of the 1970s oil crisis. However, the constraints of assembly, maintenance and cost quickly put a stop to the various projects of the time. Today, major technological advances, the cost of access to space, which is much lower than 50 years ago, and the desire of various countries to have a certain degree of energy independence, from a variety of sustainable sources, seem to have revived the momentum for orbital solar power plants. At least that is what the growing number of programs seems to indicate. Alcimed comes back on the development opportunities and describes the stakes of this new means of energy production.

The pioneers in this field are the United States and China, the latter announcing an operational station before 2030. Other promising initiatives come from Japan, the United Kingdom, and more broadly from Europe, with a desire to have solar power plants in orbit by 2040-2050.

• For more than a year, the US Air Force and the Naval Research Laboratory (NRL), using the X-37B robotic spacecraft, have been conducting experiments in low earth orbit (about 400 km) to test the capture of solar energy and its conversion into direct current electrical energy in space. The test of power transmission to Earth is expected to be conducted by the Air Force Research Laboratory (AFRL) in 2025. Northrop Grumman, partner of the AFRL, has received USD 100 million in funding to carry out the test.
• In China, the “Daily Project” team, led by Duan Baoyan of Xidian University in Shaanxi province, said the group has set a goal of having a solar power plant in space by 2028. The tests in Xidian were carried out using a 75-metre-high steel structure built on the university’s campus.
• In the UK, the government’s commitment to Net Zero led to the launch of the Space Energy Initiative in early 2022, bringing together the government with research organisations and industrial companies. Their goal is to have a first low-earth orbit solar power plant demonstrator by 2030 and a first operational system by 2040. The UK design would bring 2GW of power to the grid.
• At the European level, ESA has launched a call for new ideas for Space-based Solar Power Station (SPS or SSPS). By the end of 2021, 85 ideas were proposed, 16 were selected and will receive funding.
• In Japan, the Japan Aerospace Exploration Agency (JAXA) announced in 2014 a technology roadmap to build orbital solar power plants with a combined capacity of 1 GW by 2030. JAXA aims for a fully operational plant by 2050. In parallel, Japan Space Systems has announced that it will launch a demonstrator into orbit in 2025.