Overview Energy has emerged from stealth with an ambitious plan to transform the world’s existing solar panels into nighttime power collectors. The startup aims to achieve this by beaming energy from space. Their concept involves large solar arrays positioned in geosynchronous orbit, approximately 22,000 miles above Earth, where satellites match the planet’s rotation. These orbital arrays would harvest constant sunlight and then use infrared lasers to transmit that power down to utility-scale solar farms on Earth. This would allow those ground-based farms to supply electricity to the grid nearly twenty-four hours a day.
The company has raised twenty million dollars to date. A portion of this funding supported an airborne demonstration of its power-beaming technology, where a light aircraft successfully transmitted power via laser to a ground receiver over a distance of five kilometers, or about three miles. Their investors include the Aurelia Institute, Earthrise Ventures, Engine Ventures, EQT Foundation, Lowercarbon Capital, and Prime Movers Lab.
Declining space launch costs over the past decade have shifted space-based solar power from pure science fiction toward a more plausible reality. However, significant hurdles remain. It is still far cheaper to deploy solar panels on Earth than to launch them into space. Furthermore, the technology for wirelessly transmitting power from orbit to the planet’s surface is still in its early stages.
Overview is not alone in this pursuit. Other companies like Aetherflux are also pursuing a laser-based approach. Competitors such as Emrod and the team of Orbital Composites and Virtus Solis are developing microwave-based power transmission, which uses a different portion of the electromagnetic spectrum.
Each technological approach presents unique challenges and trade-offs. Microwave systems are less sensitive to clouds and humidity than infrared lasers, which cannot transmit through cloudy weather as water droplets would absorb much of the energy. However, microwave-based systems cannot reuse existing solar farms and must build their own ground stations. To manage costs, these ground receivers would likely be smaller, requiring tighter and more powerful energy beams. Companies are developing methods to quickly interrupt the beam to prevent harm to birds and aircraft, though this remains a concern.
Overview’s strategy of reusing existing solar farms could mitigate some issues, but the company would still need to convince the public that energy beams from space are safe and will not stray off target. It must also ensure its laser system is highly efficient; otherwise, the advantage of collecting sunlight in space would be lost during the conversion processes.
The startup has outlined a timeline, planning to launch a demonstration satellite into low Earth orbit in 2028, far below its ultimate target altitude. If that mission succeeds, Overview intends to begin transmitting megawatts of power from geosynchronous orbit by 2030.
The endeavor is undoubtedly audacious. Overview must overcome demanding physics and engineering challenges while competing against rapidly improving alternatives like grid-scale batteries, which are becoming cheaper every year, and the potential future of nuclear fusion. Yet, the belief in this technology is growing, evidenced by the emergence of specialty suppliers catering to the space-based solar power industry. It is a science-fiction vision steadily approaching reality.