Stellios Raises $5M for High-Power Microwave Systems

Stellios Technologies says it had customers before it had investors. The Austin, Texas, company came out of stealth on 20 October saying it had secured $2m in signed purchase orders before raising outside money, and has now closed an oversubscribed $5m pre-seed round, according to its announcement on PR Newswire.

What Stellios wants to build is the hardware at the heart of high-power microwave systems: the vacuum-electronic tubes, such as klystrons and gyrotrons, and the high-voltage power and control systems that drive them. Its first commercial target is megawatt-class microwave systems for defence and industry. The company names neither its customers nor its valuation, and the figures here are all its own.

Counter-drone demand is the company’s opening pitch

In defence, Stellios says its systems are designed for counter-electronics and counter-drone missions. It argues that cheap drones are driving demand for systems that can engage many targets quickly and at a low cost per shot. That is the same market Epirus is chasing with its Leonidas microwave system, which recently won an $18m US Army contract to make it mobile, as TSN reported.

The release does not say what the $2m of orders are for, beyond “initial contracted high-power microwave systems”. The company’s industrial list includes geothermal drilling, advanced materials processing and plasma heating for fusion research. It says it will design and build its systems in the US to reduce dependence on “constrained foreign and legacy supply chains”.

Investors in the round include Shervin Pishevar’s Sofreh Capital, Wave Function Ventures, Cubit Capital, Mana Ventures, Atoms & Bits, Output Capital and Erik Bruckner. Philip Carson, a partner at Cubit Capital, pointed to “signed customer purchase orders, ongoing defense customer discussions, and plans for US-based manufacturing”.

A gyrotron team with fusion on the horizon

Stellios was founded this year by Dr Richard Starson, who holds a PhD from Caltech. He previously co-founded Escape Dynamics, a microwave-powered space launch company, where members of the Stellios team designed and operated a 100 kW-class gyrotron, a high-power microwave source.

The ambitions go well beyond drones. Stellios also runs a research programme in compact aneutronic fusion, reusing many of the same parts, and says it ultimately wants fusion systems small enough to power remote military bases and, one day, supersonic and hypersonic aircraft. It gives no timeline for any of that. “The future will belong to nations that lead in power systems,” Starson said.

The money will go on delivering the first contracted microwave systems, setting up research and pilot manufacturing sites in the US, hiring engineers and leaders, and building a government sales effort, the company says. Delivery of those first systems, and the naming of a customer, will be the first real test of the order book.