Do you cover desertugly parking lots, canals or even solar lakes with solar panels, clouds will sometimes get in the way and every day the sun has to set. No problem, says the European Space Agency: just put solar panels in space.
The agency recently announced a new research program called Solaristhe purpose of which is to find out how technologically and economically feasible it is to launch solar structures into orbit, use them to use solar energy and transfer energy to the earth.
If this concept comes to fruition, Solaris could start providing sustained space-based solar power sometime by the 2030s. Eventually, this could account for 10 to 15 percent of Europe’s energy consumption, which will play a role in meeting the European Union’s goal of zero carbon emissions by 2050. “We are thinking about the climate crisis and the need to find solutions. What else can space do to help mitigate climate change, and not just watch it from above, as we have done for the past few decades?” asks Sanjay Wijendran, who leads the initiative and also plays a leading role in the agency’s Mars program.
According to Vijendran, the main driving force behind Solaris is the need for continuous clean energy sources. Unlike fossil fuels and nuclear energy, solar and wind energy operate intermittently – even the most solar farms are idle most of the time. It will not be possible to store vast amounts of energy from renewable energy sources until battery technology improves. However, according to Wijendran, space-based solar arrays could be more than 90 percent more efficient. (The other 10 or so percent of the time, the Earth will be directly between the Sun and the array, blocking out the light.)
The program, unrelated to Stanisław Lem’s sci-fi novel of the same name, is considered “preparatory”, meaning ESA has already completed a pilot study but is not yet ready for full-scale development. He calls for developing an orbital demonstration of the technology, launching it in 2030, developing a small version of a space-based solar power plant in the mid-2030s, and then dramatically scaling it up. For now, ESA researchers will start by looking at what it would take to robotically assemble large solar array modules, for example, in geostationary orbit at an altitude of about 22,000 miles. Thus, the structure will constantly stay above a certain point on the earth, regardless of the rotation of the Earth.
For the project to materialize, Wijendran and his team must determine by 2025 that it is indeed possible to create space-based solar power in a cost-effective way. NASA and the Department of Energy explored this concept in the 1970s and 80s, but was sidelined due to cost and technological issues. However, a lot has changed since then. Launch costs have come down, largely due to reusable rockets. satellites became cheaper in mass production. And the cost of photovoltaic cells, which convert sunlight into electricity, has fallen, making solar power in orbit more competitive with ground-based power sources.