H3X scales up its electric aerospace ambitions with $20M in new funding

Many industries that rely on legacy energy sources are aiming to electrify or at least streamline their operations, but for countless use cases, the tech just isn’t there. H3X is changing the game with electric motors so compact and efficient that the aerospace and marine world — not to mention investors — are taking notice.

We covered H3X’s launch from stealth back in 2021; since then, CEO Jason Sylvestre exclusively told TechCrunch that H3X has “mainly been showing that this tech works, and we’ve gotten orders from a lot of aerospace companies to prove it.”

They’ve also grown from the founding team (Sylvestre, CTO Max Liben, and COO Eric Maciolek) to a still lean 33 people — “maybe leaner than we should be.”

H3X makes electric motors, which, to be clear, does not mean full powertrains like the battery-motor-wheels combo you see in an electric car or the propeller mechanism in a plane. It’s the middle part of the equation, turning electricity into mechanical force, usually a spinning driveshaft.

What sets the company’s gear apart, though it may sound prosaic, is simply how small they are for how much power they put out. Electric motors are generally smaller and simpler than internal combustion engines. But they still need to have room for all the wiring, cooling and other components of the system, especially when they need to drive something as big as a vehicle.

As a very rough comparison, if you were using an electric motor the size of a dishwasher, the H3X equivalent — same power, same torque, etc. — might be the size of a microwave. That’s a tremendous change in industries where every inch and pound counts, like drones and small aircraft.

Sylvestre said that although their series of smaller motors (think hundreds of kilowatts) have been popular and useful, a new $20 million funding round will allow the team to complete development of their megawatt-scale motors, which they hope will change the game completely.

“We think we’re going to come in and establish a new market-leading product that will transform the aerospace and marine industries,” he told TechCrunch. “It should be a pretty stark contrast: megawatt machines would take up this whole room [i.e., an ordinary small meeting room]; ours is about two feet in diameter and about one foot thick.”

For those of you without an innate sense of how many watts are needed to do things, a megawatt motor would be able to run something on the scale of a small passenger aircraft. And that’s just where the company is seeing traction.

“We’ve seen a ton of interest in hybrid electric aircraft because you get to realize the benefits of electric propulsion, but without the drawbacks and limitations of batteries,” Sylvestre said.

Hybrid architectures have been demonstrated at a smaller scale (like a two-seater or seaplane), but with what’s out there, the math just doesn’t work out for anything larger.

Fortunately, H3X’s motors seem tailor-made for this application (and indeed in a sense can be said to be so).

First, the design is reversible, meaning it can seamlessly act as a motor or a generator, or both. This simplifies hybrid powertrains, in which a combustion engine drives a generator, and in turn powers an electric motor, which drives propulsion. That may sound unnecessarily complicated, but it allows both engine and motor to run at peak efficiency with minimal loss; many ships already run on diesel-electric hybrid engines. The gains would be compounded with two H3X units in series.

Second, because the units are small and the power electronics are built in, you can just add as many as you need to scale up.

“If you were to use a traditional megawatt class generator, as they exist today, that aircraft would have a tough time getting off the ground. And if it did, it wouldn’t fly very far,” he continued. “We’ve got two customers in commercial aviation; one is working on a 19-seat aircraft, the other on a 30-seat aircraft. But these units are stackable, so to get to higher power levels you just stack them up: you could power a 50-seat or 100-seat aircraft.”

They have contracts and customers across aerospace, marine and the military to power things like drones and small aircraft, some kind of marine racing setup (whatever that means) “and one classified one where they actually can’t tell us what it is.” (Fortunately, the tech doesn’t seem well suited for weapons development, though in a press release, investor Cubit Capital’s Philip Carson said the company has “strong traction today at the Department of Defense.”)

The marine side is another promising growth area, with much of the industry pushing to decarbonize or at least minimize reliance on the aging diesel engines that power so much of shipping and passenger traffic on the water. But the power involved is tremendous, and space on board is limited — so low volume and high output are music to the industry’s ears.

Even heavy industry, which uses generators to power some facilities or equipment, is interested. Why, when they have as much space as they need? Sylvestre said a stack of H3X units may well be simpler and easier to maintain than a traditional setup, not to mention it involves hauling a lot less metal around.

Though the company’s megawatt dreams have yet to be realized, H3X is already generating revenue. Sylvestre declined to get too specific but said it was “in the millions” last year, on track to 5x this year, with an aim of profitability in 2026.

The $20 million A round will enable the company to hire up and build out the facilities necessary to finish the megawatt units and complete their existing contracts. There’s still plenty of demand for the kilowatt-scale motors, but the megawatts are the ones that could crack open new markets.

The funding round was led by Infinite Capital, with participation from Hanwha AM, Cubit Capital, Origin Ventures, Industrious Ventures, Venn10 Capital, as well as existing investors Lockheed Martin Ventures, Metaplanet, Liquid 2 Ventures and TechNexus.

If electrification really is the next phase of shipping and local/regional air travel, it’s going to be hard to match what H3X is putting out there. But startups like this are increasingly drivers of change in legacy industries, and there’s plenty of room for everyone up there.