Space Based Solar Power is about to Transform Life on Planet Earth
U.S. government analysts have predicted that between now and 2050, energy demand worldwide will increase by almost 50%, due primarily to the use of electric cars. And by that time, renewable energy will need to overtake the share of energy we receive from traditional sources like coal, oil, and natural gas. But it will take a lot more than wind-farms and solar farms to do it.
Many experts believe solar power is our energy source of the future. It would be an understatement of the highest order to say that the sun couldn’t meet our energy needs if we could effectively figure out how to capture its energy. The sun emits 386 billion million gigawatts of energy on to the Earth’s surface, while we only consume a few thousand megawatts.
We’ve only Scratched the Surface with Solar
Our approach to solar so far has focused on trying to catch those rays that reach the earth with strategically placed solar panels. These panels are becoming more efficient thanks to the new materials, smaller components, and their ability to track the sun across the sky. At the same time, larger and larger solar farms are being deployed on land and on sea.
But that’s just a solar drop in the bucket. Where is the breakthrough that will create the sea change in technology that will get solar well past its current 2-3% share?
Reaching Out to the Sun
That breakthrough will have to solve the challenges not only of scale but of the interruptibility of solar power. Most of the solar energy approaching Earth is lost as it makes its way through the atmosphere. Then of course there’s the daytime, nighttime effect due to the Earth’s rotation.
Moving our point of solar power collection closer to the sun by creating a satellite power plant in space that continually faces the sun will address both of those issues.
The concept is called space-based solar power (SBSP) or solar power satellites (SPS). Many countries are steadily working on how to make this happen. Japan was one of the first, as I reported seven years ago.
Russia, the European Union, and India are also focused on this effort. China claims they will be collecting solar energy this way by 2030, but it’s unclear what kind of scale they’re envisioning.
The U.S. military is working on it as well, and is currently experimenting with satellite technology that can capture solar power and beam it to remote bases to ensure an uninterruptible energy supply in strategic locations. Additional military tests are planned for 2023 in which materials will be deployed in conjunction with the International Space Station.
How it Works
Imagine a massive five square mile solar sail in orbit always facing the sun. The energy it captures would be converted into energy waves and then transferred to antennae on earth via microwave transmissions. These transmissions are not affected by the earth’s atmosphere and cloud coverage as laser power beams currently are. Down on Earth, the energy is converted back into electricity. It sounds complex and futuristic, but in fact we’ve already solved the major technical barriers to make this feasible. Collection and transmission using these techniques are very doable.
The remaining challenges, though, are related to scaling. We’ll need to put a tremendous amount of material into orbit along with an army of workers to assemble it. But these challenges seem less and less daunting. Thanks to the proliferating private space industry, delivery of the material over a reasonable amount of time seems possible. And rather than relying on hundreds of workers housed in mega-sized space stations, we will program space robots to do the vast majority of repetitive assembly