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Solution to the climate crisis? Earth takes a step closer to sustainable space-based solar power

China has announced a significant step forward in their bid for space-based solar power.
China has announced a significant step forward in their bid for space-based solar power.   -   Copyright  NASA via Unsplash
By Jack Ramage

Forget solar panels on roofs, powerplants and wind turbines blighting our landscape – space-based solar power could be closer to reality than we once thought.

Testing and inspection has been completed on a new tower that could pave the way to space-based solar power in China, according to researchers at Xidian University.

The announcement means we’re a step closer to a concept long considered a potential key to solving the energy and climate crisis facing the earth.

Scientists ran a successful test on June 5 which was — according to a statement published by the university — the "world’s first full-link and full-system solar power plant".

The 246 ft (75 m) tall structure made of steel can be found on Xidian University’s southern campuses, equipped with five different systems designed to foster the eventual development of space-based solar power.

In recent years, other nations have also set their sights on space-based solar power. In March, the UK government reportedly considered a £16 billion (€18.72 billion) proposal to build a solar power station in space.

In the US, a $100 million (€95.93 million) partnership was made to provide advanced technology for their own space-based solar power system.

Japan has also made the field part of its future space exploration vision.

Science fiction or reality?

The hope of this venture is that, in theory, the satellites could continuously collect photons from the sun — converting the energy to photovoltaic cells, and wirelessly beam that electricity as microwaves back to receivers on Earth.

Although this may seem like a venture straight out of a science fiction novel, the concept of space solar power isn’t new, Dr Jovana Radulovic, Head of the Mechanical and Design Engineering School at the University of Portsmouth, noted.

"Engineers and scientists in the last century have been coming up with these ideas," she told Euronews Next.

The theory made its first appearance as far back as the 1960s, proposed by Peter Glaser, a scientist and aerospace engineer who was also president of the Power from Space Consultants.

In theory, a space-based solar power station placed in Earth’s orbit would be fruitful, due to being illuminated by the Sun 24 hours a day allowing it to generate electricity continuously.

This gives the tech a significant advantage compared with solar power systems placed on Earth, which can only produce electricity during the day and are heavily dependent on the weather.

As global energy use is projected to increase by nearly 50 per cent by 2050, this method of generating power could play a crucial role in helping meet the growing demand and tackling the climate crisis.

Space-based solar comes with significant challenges

However promising the technology may seem at first glance, this space-based solution to real-world problems comes with significant challenges too.

First, and arguably the most obvious, is the barrier of cost. As mentioned above, nations have already sunk hundreds of millions into space-based solar initiatives — and it’s for good reason.

Most systems are modular, meaning a number of solar modules are assembled by robots once in orbit. This type of assembly requires transporting all elements into space, which is difficult and costly — with a further toll on the environment.

Unless we see a massive decrease in cost of all the components that are needed to establish this solar space station, it's not going to happen as quickly as we think it is.
Dr Jovana Radulovic
Mechanical and Design Engineering School, University of Portsmouth

Another problem comes with the constraint of space itself. In order to transport the energy, the electricity would have to be converted into microwaves before being sent back to earth.

To do so, a huge antenna is needed to be built on the surface to collect the microwaves and convert them back into electricity.

"It would require a huge receiver - we’re talking kilometres across," Radulovic added.

The size of the antenna depends on the intensity of microwaves transmitted; a smaller antenna, which would be more feasible and cost-efficient, would increase the intensity of the microwaves.

However, if the intensity of the microwave signal is too much it can be damaging to objects and animals exposed to the beam.

It’s also worth mentioning that there would be at least a 10 per cent loss in energy due to the conversion and reconversion, making the energy source not as efficient as it first appears.

Likewise, huge batteries would be needed to store the solar power on Earth, which is already a huge challenge for the terrestrial solar industry.

Valuable investment in the future?

It would be challenging to make sure the solar panels survive in space too. Their vulnerability to space debris means they’d need constant maintenance and would also need to be hardened against radiation unlike on Earth.

All of these factors would significantly drive up the cost of the projects, throwing into question whether space-based solar power is actually worth it.

"This is why we’re paying close attention to what Space X is doing," Radulovic told Euronews Next.

"The idea of being able to reuse the component by using the same rocket to launch things into space over and over again - it’s clearly very cost effective".

"Unless we see a massive decrease in cost of all the components that are needed to establish this solar space station, it's not going to happen as quickly as we think it is. That is something we need to focus on," she added.

However, despite its challenges, this sci-fi-esque method of energy generation could be a valuable investment in our future.

"Sooner or later the technology will become more cost effective because there'll be more research in it — when that happens we can talk about the potential of building [space-based solar technology]," Radulovic said, noting that right now we are "very far from from that dream becoming a reality".

As the current energy and climate crisis bites, it’s apparent that drastic measures are needed to be taken to protect future generations and the planet. Whilst the technology has its short-term pitfalls, the long-term benefits of space-based solar power are promising.

The technology is also a precursor for exciting research and development opportunities. Looking forward, we’re likely to see this (and similar) space technology play an important role in the global energy supply.