Is Building a Solar Power Station in Space Feasible?
Can a solar energy collection station in space be a realistic solution? Is this an effective method to combat the pressing issue of climate change?
Solar energy beamed from space to Earth’s power grid could reach gigawatt levels. However, experts at Space Solar, the European Space Agency (ESA), and the University of Glasgow (Scotland) suggest that this process could be surprisingly safe and cost-effective.
For this colossal project to become a reality, scientists, engineers, and leading specialists will face challenging problems with few solutions.
Step 1: Design
The technology for transmitting solar energy from space to the ground is not new; telecommunications satellites have been sending microwave signals to Earth since the 1960s. However, transmitting energy to the ground power grid presents a completely different challenge.
“This idea was proposed over a century ago,” says Nicol Caplin, a scientist at ESA. “Originally, this idea was indeed rooted in science fiction. But over time, interest in this technology has changed.”
This structure is 100 times larger than the International Space Station (ISS), which took a decade to complete.
Scientists have designed and proposed various models of space solar power stations. Currently, the Solaris project under ESA is testing two designs: one that will transmit microwaves to ground stations, and another that uses a giant mirror to focus light onto a solar power farm.
Microwave energy transmission technology is gaining more popularity due to its greater potential. According to Solaris project director Sanjay Vijendran, microwave energy transmission is unaffected by weather conditions.
As noted by Andrew Glester, a well-known host of the Physics World podcast, “A facility achieving 1 gigawatt will produce energy equivalent to one of the top 5 solar farms,” and could “supply power to 875,000 households in a year.”
Initially, this large project will have to tackle several complex issues.
According to a publication in the scientific journal Nature, a space solar power station using microwave technology and capable of gigawatt output would cover an area of 1 km2. It is estimated that this facility is 100 times larger than the International Space Station (ISS), which took a decade to complete. Furthermore, the installation process would need to be carried out by robots, as the power station will not include living quarters for engineers and astronauts.
Moreover, the solar panels must withstand space radiation as well as physical impacts from space debris. They must be efficient, lightweight, and have higher performance than today’s commercial solar panels. The construction costs and transmission efficiency will present significant challenges, requiring advancements and breakthroughs in science.
Step 2: Ensuring Safety for Humans and Equipment
Since these energy stations will beam radio and microwave radiation down to Earth, concerns about health are raised.
However, according to preliminary studies, these stations are relatively safe. Expert Sanjay Vijendran states, “The only effect of these wavelengths on humans or living organisms is to raise the temperature of living tissue.” He affirms: “If you stand under such a beam with that level of energy, it’s similar to being exposed to sunlight at night.”
Illustration of a solar power station transmitting electricity to Earth.
Some experts remain skeptical, suggesting more research is needed on the effects of microwaves on humans, animals, plants, satellites, underground infrastructure, and the Earth’s ionosphere. Wireless energy transmission must not interfere with existing telecommunications and communication systems.
Even if the technology is scientifically proven to be safe, public perception may still be difficult to change. Considering the ongoing discussions surrounding 5G waves, the concept of “microwave energy transmission from orbit” may face numerous challenges.
A solar power station measuring up to a square kilometer will also face the risk of collisions with space debris, which remains an unresolved issue in the aerospace industry.
Ultimately, this large project must be environmentally beneficial. The processes of building the station, placing it into orbit, managing, and maintaining it must consider its environmental impact.
Step 3: Assessing the Value of the Space Solar Power Station
Cost remains a challenging problem to solve in large-scale solar power station projects. However, as launch costs continue to decrease, the project could become feasible in the future.
Solar power farm on Earth.
According to Sanjay Vijendran, costs could be comparable to the operating costs of current nuclear power stations, at “around $100 to $200 per megawatt-hour,” and costs will gradually decrease in the future.
He predicts that the costs of the space solar power station will eventually compete with solar and wind power, which are currently under $50 per megawatt-hour. According to data from the U.S. Energy Information Administration (EIA), solar and wind power costs in 2021 ranged from $20 to $45 per megawatt-hour.
Experts believe that once the public sees a small-scale station in orbit, proving the feasibility of this “sky-high” project, the situation will turn positive. Currently, many organizations and leading universities are researching space stations that can convert sunlight into electricity with ultra-lightweight materials, easily installed in space, and even foldable.
On the affordable rocket systems from Elon Musk’s SpaceX or Jeff Bezos’s Blue Origin, these systems will soon reach orbit and demonstrate their capabilities.
The uncertain future of a space solar power station is gradually becoming brighter over time, and one day it will transform sunlight into invisible energy beams, shooting down to Earth to supply electricity anywhere.
