Beam it Down, Scotty — How Solar Panels In Space Could Save Humanity

Lex Lei
9 min readApr 16, 2020

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Humans are a needy species. We constantly require things to be done quickly and with little effort. This makes sense from an evolutionary standpoint. However, while have we created machines and technologies to simplify everyday life, we have also correspondingly taken more of these things for granted, especially in the first world. One of the biggest things we take for granted, as we sit in our comfy heated homes while staring at a bright LED screens, is our consumption of power.

Yes, energy. It’s what drives humanity every day, from the toaster that makes your bread crispy hot, to the fuel that powers you car. We use a lot of it, and the demand for more power has left this planet scarred and choked from coal mining and burning. Humans are clever though, we have devised ways to make harvesting energy renewable and “clean”. One of the biggest sectors in this industry belongs to solar energy.

While the image of green, renewable, and unlimited energy may be tagged to solar panel technologies — and yes they are helping provide renewable energy — they are hardly completely “clean”. Here we will be taking a look into the world of solar panels and how we could be using them differently in the near future.

On the Case of Solar Panels

Solar panels are an incredibly popular form of renewable energy. Everyone is familiar with them and therefore support for this technology seemingly never ceases. Take a look at this article from Barron’s on Warren Buffet’s investment into solar energy. Here he states his confidence in the solar sector and invests big on the largest solar power plant to be build in the United States.

One might think, “Well if America’s top business magnate, investor, and philanthropist is supporting solar energy, why shouldn’t I?” Well therein lies the problem. Mr. Buffett is an investor and a business man. His credibility stands with his immense success in investments, and thus he leads others to believe that his choices are correct. He doesn’t, however, possess the background nor the knowledge in this type of technology to rightfully be making the correct conscious choice in his assumption. He bases his choice on the return in investment he expects out of this project, which could be huge.

Furthermore, in the same article, environmentalists criticize his choice, saying that the Gemini project could have massive impact to the wildlife in Nevada, including tortoises that live in the area.

Well, if you don’t really care for the tortoises crawling around in the Nevada Desert, another article has also criticized Mr. Buffet for wanting to eliminate net metering. Net metering allows people to independently install solar panels on their homes and generate their own electricity. By eliminating this, Buffett is basically saying that he wants people to pay for the energy service provided by his plant. This begs the question, are people really invested in terrestrial solar power plants for the betterment of the environment, or is it because of the money involved?

Are Terrestrial Solar Panels Really Worth it?

First, understanding how solar panels work is a good place to start when evaluating the technology.

Business aside, are Solar panels really the way to go for clean renewable energy? Well as talked about in the Ted-Ed video above, Earth intercepts a lot of solar energy every second. Our total annual energy consumption is just a small fraction of what the sun hits us with in a single day. Of course, blanketing the entire planet with solar panels is incredibly unnecessary, not to mention infeasible. Therefore, the video also talks about the many downsides of terrestrial solar panels that limits their solar harvesting potential.

Firstly, solar panels require a lot of energy to be produced. In fact, it would take a solar panel over two years to produce the energy required for its birth. This is because industrial solar panels aren’t all that efficient at capturing energy from the sun, about 15-20% efficient to be exact. These industrial solar panels also have a lifespan of around 25 years. In those 25 years dust, rain, wind, and other elemental factors damage the panels, meaning constant maintenance and upkeep is necessary. Once those 25 years are up, they have to be recycled and replaced again.

On top of those things, solar farms require vast areas of land. The sun shines differently on certain regions on Earth than others. Say Seattle for instance, a city with nearly year round overcast skies. It would be implausible nor efficient to set up solar panels here since they require adequate sunlight in order to produce a utilizable amount of energy. Therefore, solar farms must be installed in areas with year round sun and low weather fluctuations. Consequentially, this means concentrating solar farms on specific locations around the world.

Taking a look at the video above, an estimated 11,200,000 acres of land would need to be required to power the entire united states. That’s an area equivalent to the size of the state of Massachusetts. Such a change in landscape would drastically change weather cycles and ecosystems not just in that area, but for hundreds of miles in its radius.

Similarly, Elon Musk also spoke about this prospect stating, “you only need about 100 miles by 100 miles of solar panels to power the entire United States.” However, he also stated that the solar panels should be made my him. Similar to Buffet, it seems that Musk seeks personal gain from this technology. Not just this, but an entire state’s worth of solar panels in no small number, unlike what he said. Concentrating all this power in say states like Nevada or Texas would also mean that energy would need to be transferred huge distances to coastal cities.

So what is the alternative? How can we power civilization without making money hungry business giants richer while decreasing our occupancy on terrestrial land? The answer may be to send solar panels to space.

Space-Based Solar Power

Space solar power hasn’t been the most popular idea in the past. In a 2012 interview from Popular Mechanics, Elon Musk states his contempt for the idea.

In the video, his biggest frustration with space solar power is its redundancy of the power conversions that take place for it to exist. Converting solar power to electrons is not a 100% efficient system. The gist of the discussion is that photon (light) to electron conversion would have to take place twice in this system (once in space and once on the ground). He is saying that this is counterproductive, and that instead solar panels should just be left on the ground. He remarks that only 50% of the energy harvested from space solar could be usable. Additionally, he notes that the cost of sending the structure to space would be immense.

However, as crazy as it sounds, this massive orbital structure has already been tested by the Japanese Aerospace Exploration Agency (JAXA) through a much smaller prototype. This prototype proved that energy can be transmitted through microwaves instead of photons. In lab conditions, an 80% efficiency was reached from converting DC power to microwaves rather than the 50% efficiency Musk stated in the interview. Microwaves also have the added benefit that they can penetrate through the atmosphere and clouds. Being able to beam energy from space to any part of the world, bypassing the atmosphere and cloud cover, makes this technology that much more viable over ordinary solar panels.

Furthermore, the issues plaguing the solar panel industry would be eliminated through the advent of space solar. Ali Hajimiri, professor of electrical engineering at the California Institute of Technology and co-director of its Space Solar Power Project, stated that, “Above the Earth, there’s no day and night cycle and no clouds or weather or anything else that might obstruct the sun’s ray, so a constant power source is available.” Since many of the issues regarding solar power are its weather and sunlight reliance, sending panels to space where they receive uninterrupted sunlight is its biggest driving factor. With increased sun exposure and unlimited global reach, space solar could power cities around the globe regardless of their climate or sun exposure.

Going back to Elon’s remarks about the high cost associated with space solar, his own company, SpaceX, and Jeff Bezos’ private space company, Blue Origin, have developed renewable spacecrafts that can greatly drive down the cost of launching objects to space. In recent years, we have seen the potential of reusable rocket boosters with SpaceX’s Falcon 9. With this pace in space vehicle innovation, Musk may eventually change his mind in the future and invest in space solar. SpaceX and Blue Origin being privately owned companies means that millions in taxpayer money could be saved as well in the solar industry.

With billionaire money invested in sustainable technologies, there is no telling what could be done. Even recently, Bezos has pledged $10 billion towards fighting climate change. Some people have speculated that some of that money could be used for space-based solar power research and development.

The Current Status of Space Solar

Essentially, the Space-based Solar Power Station developed by JAXA is a massive dual solar panel array in low Earth orbit. With no clouds in the way, two reflective mirrors redirect sunlight toward these solar panels 24 hours a day, 7 days a week, essentially tripling the solar panel’s sun exposure. The energy produced from these solar panels are then converted to a microwave beam. Receivers on the ground surface would then receive this beam and convert it back to electricity. Apart from the receivers, installation of space solar would require zero land usage. This could greatly benefit habitats under threat by the terrestrial solar sector.

JAXA has also made plans to complete a full scale 1GW solar power station by the year 2030. However, Japan is not the only country looking at space for energy harvesting potential. China, also coming into contention, has big plans for space solar in the future.

With so much increased attention towards space solar and its potential, we may soon see government agencies and privately owned space companies, like SpaceX, investing in it. If this technology does successfully deliver on its promises, the future of solar panels could eventually lie in space.

Final Word

Space, the final frontier. It’s vastness has left humans pondering it since our ancestors first looked up at the sky. However, its existence has also answered so many question humans have had for thousands of years. It almost seems poetic that space could one day free humanity from the shackles of our energy problem. While there are disputes about the plausibility of space solar, opinions from business magnates should be taken with a grain of salt. The solar sector has huge monetary potential for investors, so it makes sense that a risky investment, such as space solar, is pushed to the back of anyone’s mind. It is important to instead listen to the scientists, engineers, and researchers who have dedicated their careers and lives to the potential of this technology. The potential to provide uninterrupted clean energy to all parts of the world is something that these scientists want to see become reality. What transpires in the next decade regarding space solar may decide the course of solar power for generations to come. Let us hope that the gamble Japan and China have taken pays off, and that the promises of space solar becomes a reality.

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Lex Lei

Civil Engineering BS Candidate at Northeastern University