As the global auto industry accelerates toward an all-electric future, a tiny 23-pound internal combustion engine from a little-known company in Washington State is raising eyebrows—and questions.
Developed by Avadi Engines, the MA-250 is a compact, lightweight internal combustion engine (ICE) designed to deliver efficiency without the complexity of traditional powerplants. Publicly unveiled in 2023, the MA-250 is part of a growing countercurrent to the dominant EV narrative—one that suggests there may still be room for combustion-based innovation in a post-carbon world.
“We’re not fighting electrification. We’re offering another tool—one that works now,” Avadi’s website states, reflecting the company’s positioning of the engine as a complementary technology, not a competitor.
A Mechanical Rethink
The MA-250 was developed over two decades by Avadi’s co-founder and former CTO, Michael Arseneau, before he stepped down in early 2023. According to the company, the engine eliminates the crankshaft entirely and uses a scissor-like rotary motion with dual connecting rods and pinion gears, combined with a rotating valve disc to complete the four-stroke combustion cycle.
The result? Fewer moving parts, a substantial reduction in weight, and what the company asserts is an impressive brake thermal efficiency of 42.12%. This figure surpasses most conventional combustion engines, which usually operate at an efficiency of around 20–30%.
Avadi says the MA-250 produces 16 horsepower and 30 Nm of torque at around 3,700 RPM. These are modest figures by today’s automotive standards, but the company isn’t targeting performance vehicles. Instead, it’s looking at applications where lightweight, low-emission, and portable power are critical—think drones, small vehicles, portable machinery, and aviation support equipment.

Between the Present and the Plug
While automakers like GM, Ford, Toyota, and Volkswagen have committed to phasing out ICEs by 2035, Avadi argues there are still significant segments of the global economy—and geography—where full electrification isn’t yet viable.
In a 2023 blog post, Dale Renner, Avadi’s Vice President of Program Development, described the MA-250 as a “transitional solution,” particularly in sectors without charging infrastructure or where batteries’ energy density remains a limitation.
“Not every industry or geography can afford the leap to electric,” Renner wrote. “We offer a transition that doesn’t require a blank-slate rebuild.”
A Question of Utility—And Urgency
With EV battery production under increasing scrutiny, the MA-250 is a welcome addition to the conversation. Today’s batteries depend on lithium, cobalt, and nickel, all of which have a large ecological footprint and human rights implications.
Avadi’s engine still burns fuel and emits CO2, but the company argues that in some circumstances, a highly efficient, low-emission ICE may be the better option than a combustion engine, particularly if it is paired with biofuels or synthetic fuels.
That argument remains controversial. While Avadi has released technical white papers on its site, the engine’s efficiency and emissions claims have not yet been independently verified by a third-party lab or peer-reviewed publication. Nor are there published pilot programs or commercial partnerships that show the MA-250 in operational environments at scale.
The Regulatory Gap
Avadi’s innovation also sits in a regulatory gray area. In the United States, there is currently no dedicated framework or incentive structure for ultra-efficient ICE technologies, unlike the extensive subsidies available for EV makers. That could make commercialization an uphill battle—unless Avadi can secure industry partners, demonstrate real-world use cases, or attract attention from sectors beyond passenger vehicles.
And while early reviews in engineering circles have noted the novelty of the design, industry observers caution against overstating its impact without independent validation.
A Modest Machine with a Big Question
The MA-250 isn’t going to replace Teslas or derail the EV transition. But it does raise a compelling question: Is electrification the only path forward?
Avadi’s answer is no—or at least, not yet everywhere. Its tiny engine may never make headlines like a Cybertruck or spark debates on Capitol Hill, but in parts of the world where the electric future remains aspirational, innovation in combustion might still have a role to play.
In a transport ecosystem that increasingly demands both agility and sustainability, the road forward might not be a single-lane highway—but a network of interwoven paths, some electric, some old-school, and some entirely reimagined.