20 Reflectors Proposed by Researchers to Be Installed in Orbit 1,000 Kilometers From Earth

Engineers at the University of Glasgow have unveiled a new concept that could dramatically increase solar power production and accelerate the world’s transition to renewable energy. Their study shows that placing large reflectors in Earth orbit could bounce additional sunlight onto solar farms even after sunset, boosting daily energy yields.

Using sophisticated computer simulations, the researchers modeled how different configurations of thin, kilometer-wide solar reflectors in low-Earth orbit could generate surplus sunlight for ground-based solar parks.

Their findings, published in the journal Acta Astronautica, demonstrate that deploying just 20 spider-silk-thin reflectors around 1,000 km from Earth could reflect solar rays onto farms for an average of two extra hours per day.

The orbital reflectors would maintain a near-Earth orbit along the planet’s terminator line – the boundary between day and night. They would be arranged in a “Walker constellation” formation commonly used for satellite communications, where objects are evenly spaced to create continuous coverage from above. The team developed an algorithm to determine the optimal positioning and angles for intercepting and efficiently redirecting sunlight.

Their simulations calculated the additional mirrors could produce 728 megawatt-hours of electricity daily – equivalent to adding an entire large-scale solar farm but without the construction costs.

Distributed strategically, this surplus sunlight could boost output from parks worldwide, especially in early mornings and evenings when demand peaks. Productivity could be further increased by deploying more reflectors or enlarging their size.

According to project lead Dr. Onur Çelik, Solar energy has great potential to accelerate our transition to net zero by reducing reliance on fossil fuels and curbing climate change. As panel prices fall, large-scale solar deployment is growing globally. However, generating power is limited to daylight hours. Orbital reflectors could maximize efficiency at solar farms for years to come.

Principal investigator Professor Colin McInnes notes that while the concept dates back to the 1920s, reflectors have only been tested once before on the Russian Mir space station in the 1990s. SOLSPACE works to develop an orbital mirror technology that could supply global clean energy on a much grander scale. Addressing climate change requires bold ideas. Though ambitious, orbital reflectors leverage proven principles and our models show real promise to scale up sustainability solutions.

In summary, engineers believe this relatively low-cost and scalable innovation could play a key role in expediting the world’s transition to a net zero carbon future through round-the-clock solar power generation from space.

Sources

University of Glasgow | Onur Çelik, Colin R. McInnes, A constellation design for orbiting solar reflectors to enhance terrestrial solar energy. Acta Astronautica vol.217, April 2024, Pages 145-161, doi.org/10.1016/j.actaastro.2024.01.031