Silicon solar cells could cut the cost of powering satellites by up to 90%, according to a new study led by the University of Surrey in England.
The researchers said the switch could also cut the weight of solar cells a spacecraft needs by about half. Phys.org reported on the findings.
“The interesting finding for us was not that silicon is cheaper but where the remaining cost sits,” said Tommy Richards, the review’s first author. “Once you put silicon cells behind space-qualified glass, the glass is what you are paying for.”
The review was published in the journal Acta Astronautica. It compared silicon cells with triple-junction cells, which have been the normal choice for spacecraft for many years.
Triple-junction cells are made with materials such as gallium, indium and germanium. According to the study, they cost about $250 to $450 per watt.
Silicon costs only tens of cents per watt. As of November 2025, three main silicon designs known as PERC, TOPCon and heterojunction averaged $0.275, $0.285 and $0.39 per watt.
The cells have also become more efficient. Silicon heterostructure cells have reached 27.8% efficiency, while perovskite and silicon tandem cells have reached 34.85%.
To test the idea, the Surrey team modelled two spacecraft. One was a single side of a small 3U CubeSat. The other was a Micro Sat built by Surrey Satellite Technology Limited.
Even after adding protective glass approved for use in space, the study found savings of about 85% to 90%.
The researchers found that this cover glass is now the biggest cost for silicon solar arrays. They said the next task is to protect silicon in space without adding too much cost and weight.
“If we can make the cell itself tougher against radiation, we can use thinner glass or substrates, and we cut cost and weight at the same time,” Richards said. “It reframes the problem from a materials contest into an engineering one we know how to attack.”
According to the report, lighter satellites need less launch mass. This can leave more room for fuel or scientific instruments on board.
The report said cheaper hardware could make it easier for companies and governments to expand satellite services. These include weather forecasting, communications, GPS and monitoring of the Earth.
It said such services help cities respond to extreme weather, support farming and improve emergency planning.
Silicon is not new to space. From 1958 to 1977, it was the standard solar cell material for spacecraft.
Gallium arsenide cells later replaced silicon because they were more efficient and handled radiation better. The study said silicon designs have since improved a great deal, which could bring the material back into orbit.
Source: this article is based on reporting by Yahoo Tech. Image: Yahoo Tech. Written with the help of AI and published by the Tzaneen Voice Technology desk. See our Editorial Standards.
Werner Jacobs covers technology for Tzaneen Voice. Werner reports on mobile networks, data prices, internet access, smartphones, apps, AI, cybersecurity and South African tech companies. Each story explains what a new product, price change or policy means for ordinary users in South Africa.