Aetherflux raises $50 million for space-based solar power

WASHINGTON — A startup taking an alternative approach to space-based solar power has raised $50 million as it works towards a first demonstration mission next year.

Aetherflux announced April 2 it raised a $50 million Series A round led by Index Ventures and Interlagos. Several other funds and individuals participated in the round, including Breakthrough Energy Ventures, Andreessen Horowitz and NEA.

The startup announced plans last October to develop a constellation of satellites that would collect solar power and beam it to Earth using lasers. The approach is a departure from previous concepts for space-based solar power, which have traditionally involved giant spacecraft operating in geostationary orbit and transmitting power using microwaves to rectennas on the ground.

Baiju Bhatt, founder and chief executive of Aetherflux, said in an interview last October that the “all or nothing” approach of those earlier designs was a major reason why there has been little progress on the concept, which was first proposed more than a half-century ago. “Our main observation is the reason it hasn’t happened is because that design is not one that you can iterate on,” he said then.

Bhatt initially self-funded the company, providing about $10 million to get the venture started. He is the co-founder and former co-chief executive of Robinhood, a financial services company.

In its announcement of the new funding round, Aetherflux said it has demonstrated power transmission in the lab as it works on a demo mission slated for launch in 2026. The new funding will allow the company “to move even faster,” it stated, but did not elaborate.

Aetherflux has identified defense as an early market for its technology, offering a way to get power to forward operating bases. That was a concept endorsed by a report by the former National Security Space Office in 2007 on space-based solar power, although the Defense Department did not implement the recommendations of that report.

The company said it secured government funding for a study related to its concept through the Defense Department’s Operational Energy Capability Improvement Fund (OECIF). That funding, Aetherflux stated, would support “a proof of concept demonstrating power transmission from LEO.”

The company did not disclose how much funding it received. According to the OECIF website, the project is one of 45 approved for funding, but does not identify how much funding is available to the project or overall program.

One of the investors in Aetherflux’s Series A round acknowledged the major challenges involved with space-based solar power. “On the surface, the business he described seemed wildly complex — launching satellites with solar panels into orbit and wirelessly transmitting power around the globe — to say nothing of the regulatory and compliance challenges,” Jan Hammer, a partner at Index Ventures, said in a statement about a conversation he had with Bhatt about the company.

However, he said he was convinced that the company has thought through how to overcome those obstacles. “This is a big bet, but it’s the kind of bet we like — on a founder we know and trust, tackling a problem that matters, with a plan grounded in reality. The future of energy is in space.”