Send this article to a friend:


The Next Leg Of The Space Race Is All About Solar Power
Haley Zaremba

One of the biggest problems facing solar energy is that it is variable. Solar production waxes and wanes according to variables well outside of human control. The amount of sunlight hitting a solar panel in a given day depends on the weather and the season. Further complicating the issue, the times of day when demand for energy is highest are often opposite of peak production hours. Solar panels are just clocked out when all of us get home and turn on our lights, start cooking, and our heating systems work harder to keep the house warm as the sun goes down. 

At a very basic level, energy variability is the enemy of energy security. A successful green energy transition must therefore find a way to account for and work around the predictable ups and downs of renewable energy production as well as the unpredictable ones, especially as weather patterns begin to change and extreme weather events grow increasingly common in the context of global warming. 

Furthermore, this variability poses major complications to energy security and to our aging grids, which were not designed with variable energy sources in mind. Our energy grids were designed to accommodate what are known as baseload powers, such as fossil fuels and nuclear energy, which can maintain a steady output and be manipulated as needed to respond to variations in energy demand throughout the day and through different seasons. 

One solution to these problems is long-term energy storage, a burgeoning field with massive growth potential. Currently, we are depending on lithium ion batteries to store excess renewable energy at peak production hours, which is then released onto the grid when demand outstrips supply. The issue with this is that lithium-ion batteries can only store energy for a matter of hours, when we really need to be able to store energy for whole seasons. Long-term energy storage solutions are still largely in the research and development phase, however. 

Other scientists are trying to find a way to make renewable energies into baseload powers. This goal goes against the laws of nature here on Earth, so they’re looking to the stars. Sending solar panels into space would allow them to soak up a steady supply of light without interference from weather patterns and limited daylight hours here on Earth. While the idea of sending solar farms into outer space has been around for 100 years, it has largely been the stuff of science fiction – until now. 

Thanks to increasingly affordable infrastructure and the falling cost of space launches, there is a new space race unfolding around the world. One prototype of a space-based solar power system built at the California Institute of Technology (Caltech) is scheduled to begin experiments in Orbit later this month. Another initiative by the European Space Agency (ESA) is on track to be fully ready by just 2025. Meanwhile, “China has announced plans to put a megawatt-scale demonstration unit in low Earth orbit in 2028, before deploying another system to a more distant geosynchronous orbit in 2030,” reports Nature.

These plans are ambitious, to say the least. In order to be viable, space-based solar power will have to be deployed on a massive scale. Plans for such orbital solar farms are kilometers wide, and will be built about 36,000 kilometers (about 24,000 miles) into the Earth’s atmosphere. And the receivers here on Earth receiving this energy beamed from space will have to be even larger than the solar farms themselves. These real estate needs alone present major hurdles for the buildout of these plans, as terrestrial solar farms are already facing major land use challenges.

The timelines touted by competing research groups around the globe might be a little bit optimistic, but it’s certainly not impossible. “There’s nothing outlandish in this that would require new physics,” says James Carpenter, who is currently leading a feasibility study for ESA. “Economically, it’s comparable, for example, with nuclear power.” In fact, some argue that the real economic liability would be failing to invest in space-based solar power. The technology holds immense promise for international energy security and global decarbonization at a time when those imperatives have never been more urgent. 

By Haley Zaremba for






Haley Zaremba is a writer and journalist based in Mexico City. She has extensive experience writing and editing environmental features, travel pieces, local news in the Bay Area, and music/culture reviews.


Send this article to a friend: