Space-based solar power is the cool technology of the future, although the concept was conceived hundreds of years ago. Konstantin Tsiolkovsky, a Russian scientist, proposed the idea of harnessing space-based solar power in 1923. Years later in 1941, American writer Isaac Asimov based a science-fiction story on this concept, in which a solar power satellite beams energy down to our home planet and even to the other settlements in the solar system. The concept has been around for a long time, but it wasn’t seriously considered until the 1970s, during the golden age of space flight.
Now it’s back! The idea has progressed from science fiction to reality, and it is gaining mainstream attention in the midst of the climate crisis. In a groundbreaking experiment, European aerospace company Airbus recently demonstrated how solar power could be beamed from space — albeit on a small scale.
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What is space-based solar power?
Space-based solar power is the process of harvesting the Sun’s energy in space and transmitting it back to Earth for usage. To accomplish this lofty goal, a constellation of space solar panels must be launched into Earth’s orbit, forming a space power station to harness solar energy. The main components include self-assembling solar panel satellites, reflectors and microwave or laser power transmitters.
Reflectors or inflatable mirrors scattered across space collect sunlight and direct it to solar panels. The collected solar energy is then converted into microwaves or a laser, and transmitted via “rectifying antennas” to Earth. On Earth, the beam is collected by power-receiving stations and finally, supplied via electric grid systems.
Why a space-based solar power station?
This entire process of beaming solar energy back to Earth is extremely expensive, but it offers one of the most significant advantages, i.e., direct access to the Sun’s indefinite energy.
Unlike on Earth, the atmosphere in space does not absorb or scatter solar radiation. This allows photovoltaic cells to collect more energy in space without being obstructed by clouds.
Only 48% of solar energy is estimated to reach the Earth’s surface. The remainder is obstructed due to absorption by gases and dust found in the Earth’s atmosphere. The Earth’s atmosphere also reflects 23% of the Sun’s rays back into space. Therefore, a lot of energy is being wasted in attempts to harness it on Earth.
Another advantage is that the energy can be harnessed 24 hours a day, seven days a week. This could be accomplished by putting the solar power satellites in the proper orbit to avoid the night.
However, there are several engineering challenges that need to be addressed, like deploying large-scale infrastructure of solar panels into space, which remains a herculean task. Along with this comes the challenge of maintaining its operation in order to properly harness solar energy for a longer period of time.
The Airbus experiment
Airbus demonstrated how solar power could be beamed from space in September 2022. This was a small-scale experiment, but it was successful enough to suggest that this technology could be the future of clean energy.
It took place in Germany at Airbus’ X-Works Innovation Factory. The wireless transmission system managed to disseminate green energy at 118 feet in this experiment. The beamed energy was used to power a hydrogen generator and a fridge, as well as to light up a model city.
The team engineers hope to expand its range and test it over a longer distance in the coming years, eventually reaching all the way to space.
“We advocate a stepped approach to scale the system: from the ground to aerial systems, then in space. This could in fact be a game changer for aircraft, with the potential to extend the range, and reduce the weight, but also to relay power to other places, managing energy like data. This has raised a lot of interest in the energy sector. In the end, this will be a joint effort with institutions and the energy industry,” explained Jean-Dominique Coste in a press release.
This cutting-edge technology has the potential to revolutionize aviation. The technology’s applications, however, go far beyond the aerospace industry.
The innovative solution is expected to be a game changer as the world attempts to slow down global warming by slashing emissions. More than 60% of energy is produced using fossil fuels, like coal. And predictions indicate that there will be an increase in energy demand by 2050.
Solar power from space is an excellent source of clean energy. It is about 50% more intense in space and can generate significantly more energy than those of the same plant size on Earth.
Space-based solar power innovation has numerous advantages, including the use of less land than traditional renewables and the provision of energy to areas that do not currently have reliable power. Furthermore, this technology has the potential to solve the problem of future energy shortages by powering cities, factories, homes and, eventually, airplanes.
Several other experiments are also in the works. For example, Caltech scientists are working on the Space Solar Power Demonstrator (SSPD) to test key technologies.
Furthermore, governments, including the United Kingdom, the United States and China, are working on this technology. The European Space Agency has also approved Solaris, a study to assess the feasibility of large solar farms in space.
Great minds and technological advancements have been driving society, and it will not be long before space-based solar power becomes a reality.
Images via Airbus