ESA has signed contracts for two concept studies for commercial-scale space based solar power plants – a vital step in its new SOLARIS initiative.
The concept studies for commercial-scale space based solar power plants will serve as an up-to-date reference for the overall SOLARIS effort, maturing the feasibility of gathering solar energy from space. Led by Arthur D Little and Thales Alenia Space Italy, respectively, the parallel contracts are due to be completed before the end of 2023.
The importance of space based solar power
Space based solar power gathers solar power where it is continuously available and in plentiful supply – in the Earth’s orbit. The gathered power is then sent down wirelessly to Earth where it is needed for clean energy.
Space based solar power complements terrestrial renewables, making power available reliably on an ongoing 24/7 basis. It has the ability to provide much-needed stability to the electricity grid as the share of intermittent renewables continues to increase – reducing the dependence on large-scale storage solutions.
Utilising space based solar power for Europe’s energy future
The SOLARIS initiative, approved at the ESA Council in November 2022, will undertake studies and technology developments to assess the benefits, implementation options, commercial opportunities, and risks of space based solar power as a contributor net-zero efforts in Europe.
The results from the initiative should allow Europe to make an informed decision on proceeding with a full development programme for commercial-scale space based solar power by the end of 2025. This will begin with a subscale in-orbit demonstrator to beam power from space to Earth.
“These contracts are for the first European concept studies of space based solar power for more than 20 years, so today marks an important step,” noted Sanjay Vijendran, ESA’s lead for SOLARIS.
“We are really starting from a blank sheet of paper to get an up-to-date design for what working solar power satellites could look like, sourcing promising ideas from everywhere we can, and leveraging the latest advancements in space and terrestrial technologies.
“The studies will look at as wide a range of options as possible, including investigating all the different ways to move the energy, safely and efficiently, down to Earth: radio frequency transmission, lasers and simply reflecting sunlight down to solar farms on the ground.
“And we are happy that we have major energy players like the French electricity utility ENGIE and the Italian utility ENEL, included as members of the study consortiums, reflecting the potential value the energy sector is already seeing in this capability for the future. It’s important that we engage the energy sector right from the start of this development and listen to their needs, so we know from the beginning that we are building something that end users will want and use.”
The results of the concepts will dictate further studies
The concept studies are being implemented by ESA as though they are flight projects – which is unusual for system concept studies at an early phase. This is because their results will dictate the follow-on studies planned for a sub-scale demonstrator mission as well as research projects into specific key technologies that SOLARIS will support.
The two studies are funded by ESA’s Preparation element, part of its Basic Activities, which supports new ideas in space missions and technology.
“These activities demonstrate the importance of ESA’s Preparation element in supporting ambitious ideas to become a reality,” said Leopold Summerer, heading ESA’s Advanced Concepts and Studies Office. “Preparation-funded activities help ESA assess the interest from European industry in novel topics and lay the groundwork for future research and technology development to make them happen.”
Global interest in energy from space is rising
In the US, Caltech’s Space Solar Power Demonstrator satellite was launched into orbit in January to test key technologies including space-space microwave transmission of solar energy. China has a demonstrator mission planned for 2028, with a ground-based wireless power transmission test facility in place, and Japan plans to fly its own demonstrator in 2025. Also, the UK Government has been in talks with Saudi Arabia to supply its Neom smart city region with carbon-free electricity from space.
“There are a lot of fundamental reasons why space based solar power is looking a lot more feasible and desirable than ever before,” added Sanjay. “These include the reduced cost of launch to orbit with the advent of reusable launchers, the reduced cost of satellite hardware through mass production – seen with new constellations such as Starlink and OneWeb – and trends towards very modular solar power satellite designs.
“In addition, space robotics and in-space assembly and servicing technologies have really come a long way in the last two decades, which will be essential for the construction and maintenance of solar power stations. Finally, the sheer challenge of transitioning to net zero within the next 25 years with existing technologies – and the consequences of not doing so – demands exploration of alternative solutions that could help make sure we achieve our goal.”
