Acceleron Fusion: Cracking the Code of Muon-Catalyzed Fusion Energy
Our energy grid is under immense pressure. Data centers, the backbone of our digital economy, are gobbling up power at an insane rate. We need abundant, reliable, carbon-free energy—and we needed it yesterday.
Fusion is one the most promising potential solutions. It’s clean, safe, reliable, compact, and fuel is practically infinite. The catch? It’s ridiculously hard to pull off. Most approaches involve plasma hotter than the sun, which is about as easy to handle as it sounds. But Acceleron Fusion isn’t playing that game. Acceleron Fusion is focused on muon-catalyzed fusion.
This isn’t your typical moonshot. It’s a Mars shot, with Earth-shattering potential. If Acceleron cracks this, we’re looking at an energy revolution that could redefine our technological and economic future. It’s audacious. It’s high-risk. And it’s exactly the kind of bet we love to make.
We need breakthrough innovation, and Acceleron Fusion is swinging for the fences.
Muon-catalyzed fusion involves replacing electrons with muons, which are subatomic particles similar to electrons—but about 200 times heavier. Bombarding fusion fuel with a beam of muons, which replace electrons in the fuel’s atoms, sidesteps the need for plasma and vastly reduces the temperature required to sustain fusion—think 1,000°C instead of 100,000,000°C. Acceleron Fusion is developing a high-density fusion cell to allow each muon in the beam to catalyze more fusion reactions than have been demonstrated previously, as well as a high efficiency muon source to produce muon beams using less energy.
The idea of muon-catalyzed fusion has been around since the 1950s, but the approach fell out of favor because muons proved difficult to produce in high numbers, and optimistic projections suggested plasma confinement-based fusion would work sooner than it has. Founders Ara Knaian and Seth Newburg had the confidence to revisit these assumptions. They believe that advances in accelerator technology, high-strength materials, and computational simulation codes over the past 30 years have greatly improved the feasibility of designing and building a muon catalyzed fusion plant.
Ara is an electrical engineer with advanced degrees from MIT and an inventor on 36 patents. Seth holds a B.S. in mechanical engineering from MIT and a Ph.D in biomedical engineering from Boston University. They spun the business out of NK Labs, a product design consulting firm they founded, after receiving a $2M ARPA-E grant in 2020. Based in Cambridge, MA, they have been working with leading physics researchers and labs such as the Paul Scherrer Institute, Fermilab, Oak Ridge National Laboratory, Argonne National Lab, and several universities.
In October 2024, Acceleron achieved a significant technical milestone by running its fusion machine at higher pressures than those at which muon catalyzed fusion rates had previously been measured. Acceleron has collected data on more than 100 hours of continuous fusion in its machine.
Today, the cheapest source of 24/7 electricity is natural gas, with a levelized cost of electricity (LCOE) of roughly $0.037/kWh. Acceleron is targeting a LCOE of $0.025/kWh, a clear example of how they pass the villain test—abundant power with no waste—and why we are excited to partner with an incredible team working on the holy grail of energy production: nuclear fusion.
Acceleron joins a best-in-class portfolio of founders and companies working to design, build, and scale cost-competitive, clean fusion energy. We’re proud to support leading companies like Commonwealth Fusion Systems and Radiant, as well as emerging startups like Marathon Fusion, Blykalla and Alva Energy, who are working on the front lines and behind the scenes of nuclear energy science and production.
We’re thrilled to announce that we’re co-leading the company’s Series A round alongside our friends at Lowercarbon Capital. Not to mention, Acceleron is actively hiring! If you’re based in the Boston area, and want to be a part of something that’s going to change the world, check out their jobs page to review open roles.