Overview Energy transmits solar energy to the ground from an altitude of 15,000 feet, the next step to challenge orbiting satellites
Overview Energy uses near-infrared lasers to deliver space power to existing solar panels, striving to free power generation from day and night constraints, but the climate and efficiency still need to be verified.
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A Cessna Caravan aircraft rose to 15,000 in November this year Feet high in the air, an invisible near-infrared laser is fired at the solar panel on the ground, instantly lighting up the power reading on the instrument panel. This experiment conducted by the startup Overview Energy shows that sending "sunlight from the sky" directly into the existing power grid is no longer just a laboratory paper, but a business plan that may be bet by venture capital.
Near-infrared experiment at an altitude of five kilometers
Overview Energy’s test was conducted over the desert in the southwestern United States. The aircraft continued to hover, and the laser beam passed through the thin cloud layer and still hit the commercial polycrystalline silicon plate on the ground, outputting "several kilowatts" of power. According to Solar Daily, this is the first time that "wireless power transmission", a long-term focus of space solar energy, has been implemented with available power.
Overview Energy explained that the next step is to move the transmitter to a low-Earth orbit satellite so that the same laser can power ground-based solar panels at night.
Laser route and cost strategy
Compared with mainstream microwave solutions that require several square kilometers of rectennas, Overview Energy's biggest advantage is that "the ground solar receiving panels do not need to be redone."
The laser wavelength is close to that of sunlight and can be directly absorbed by standard silicon substrates. The company estimates that after the existing solar arrays with installation capacity of hundreds of gigawatts around the world are connected to lasers, daytime illumination and nighttime lasers will complement each other, and the unit capital utilization rate is expected to increase from about 25% to nearly 100%.
This kind of thinking attracted EQT Foundation and Lowercarbon Capital to participate in a $20 million seed round of investment because it focuses expenditures on the space end and launch, avoiding the heavy costs of land and infrastructure.
Weather restrictions and technical risks
However, when near-infrared rays encounter thick clouds or heavy rain, the attenuation will increase sharply, and the transmission efficiency may drop to zero. This puts the technology originally used to solve the intermittency of solar energy once again facing the risk of climate-induced outage.
In addition, the information disclosed by Overview Energy so far only mentions "several kilowatts" of instantaneous output, leaving gaps in terms of end-to-end efficiency, jitter control of light beams in turbulence, and high-frequency safety shutdown mechanisms. For a start-up that plans to launch a low-orbit satellite in 2028 and start commercial power supply in 2030, these physical and engineering issues will directly affect capital requirements and mass production schedules.
Next stop: space and market verification
US government agencies are also observing the feasibility. The Defense Advanced Research Projects Agency (DARPA) completed an 8.5-kilometer surface-to-surface laser transmission demonstration this summer, demonstrating dual-use potential. At the same time, China has chosen to build large-scale microwave power stations in a 36,000-kilometer geostationary orbit, moving towards large-scale national infrastructure construction.
The two strategies are like the battle between consoles and personal computers in the Internet age: Should we pursue a single point of all-weather power supply, or should we break through with a decentralized, small, and rapidly iterative optical system? It is still difficult for the market to draw conclusions at this stage.
But Overview Energy’s experiment proves at least one thing: space power generation does not have to wait for giant power stations that are far from finalized, and there are already paths to integrate with ground assets. If it can subsequently maintain stability in a changing atmosphere and prove that clear nights alone can bring positive cash flow, every silicon chip in the world's devices may be revalued.
Whether it can penetrate the clouds and investors’ doubts will determine whether this laser light can really open a new chapter in the renewable energy market within 24 hours.
