Montréal, Canada – September 15th, 2025 – FeX Energy, a McGill University spin-out and flagship venture of Hard Climate, today announced the close of an oversubscribed USD $3.5M (CAD $4.78M) seed round. The financing will accelerate deployment of FeX’s first pilot project and expand the team as the company prepares for early growth.
FeX Energy is developing iron-based long-duration energy storage, a breakthrough technology offering unparalleled energy density, ease of deployment, and storage stability without self-discharge. These attributes make it especially well-suited for displacing high-cost fossil fuels in remote and hard-to-access locations.
“Reaching this milestone is a moment of gratitude and celebration. The team has created real value and we’re ready for the next stage of growth,” said Hayden Smith, CEO of FeX Energy.
“Our mission at FeX is to empower industry decarbonization with iron energy – affordable, safe, and globally abundant. With this seed funding, and the strong alignment of our new investors, we are well positioned to demonstrate how our solution can replace high-cost fossil fuels in even the most remote and challenging locations, while laying the foundation for scalable growth across global energy systems.”
The round is led by Fathom Fund, a Houston-based deep-tech venture capital firm with strong ties to the global energy industry. As a lead investor, Fathom will leverage both its capital and sector expertise to help FeX reach the largest greenhouse gas emitters searching for economic pathways to decarbonize.
“At Fathom we have looked at practically every long-duration storage solution in the market. FeX’s thermochemical approach stood out for its unique combination of unparalleled energy density, stability of storage without self-discharge, and reliance on abundant low-cost iron,”
said Paul Sheng, Managing Partner of Fathom Fund. “We believe this is a breakthrough solution with the potential to decarbonize some of the most difficult sectors of the energy system, and we are excited to support Hayden and the team with capital, industry connections, and follow-on investment for growth.”
Alongside Fathom, Amplify Capital is the anchor Canadian institutional investor in the round. A leading impact venture fund, Amplify brings a decade-long track record of backing climate technologies and hardware-enabled business models aimed at driving deep decarbonization.
“FeX exemplifies the kind of bold, scalable solution Canada can contribute to the global energy transition, combining scientific excellence with a clear pathway to industrial decarbonization,”
said Trish Nixon, Venture Partner at Amplify Capital. “What impressed us was not only FeX’s breakthrough technology, but also the team’s commitment to building with purpose, impact, and integrity. We look forward to helping FeX strengthen its Canadian presence while supporting its journey to become a global leader in long-duration energy storage.”
The round also includes Antares Ventures, a Singapore-based deep-tech fund known for supporting Canadian companies with entry into Asian markets. Their participation underscores FeX’s long-term international potential.
“Industrial heat is one of the hardest points in Asia’s energy transition. FeX Energy offers a distinctive solution to leverage renewable energy to generate high-quality temperature at a scale and cost that heavy industry requires,”said Michael Gryseels, Founder and Managing Partner of Antares Ventures. “Antares is excited to support FeX as they are launch and expand into Asia’s growth markets.”
The journey of FeX Energy began at McGill University’s Alternative Fuels Lab under Professor Jeffrey Bergthorson. It was then launched as Hard Climate’s flagship venture, designed to scale breakthrough clean technologies with global impact.
“FeX represents the kind of world-changing innovation Hard Climate was created to support,”
said Marc Guilbert, Ph.D., CEO of Hard Climate. “From its origins in McGill’s Alternative Fuels Lab to today’s seed round milestone, FeX embodies both the scientific excellence and the entrepreneurial drive needed to deliver meaningful climate solutions at scale.”
With this investment, FeX Energy will focus on executing its first pilot project and expanding its consortium of industry partners.
About FeX Energy
FeX Energy is a Canadian cleantech company developing iron-based long-duration energy storage to displace fossil fuels with affordable and scalable clean energy. Founded out of McGill University’s Alternative Fuels Lab under Professor Jeffrey Bergthorson, FeX Energy is the flagship venture of Hard Climate. The company’s values – impact, care, and trust – guide its mission to empower industry and communities with iron energy.
About Fathom Fund
Fathom Fund is a Houston-based deep-tech venture capital firm with strong ties to the global energy industry. The fund invests in transformative hardware solutions that address climate change and industrial decarbonization, bringing both capital and deep sector expertise to scale breakthrough technologies.
About Amplify Capital
Amplify Capital is a Canadian venture fund with over $90M in assets under management, investing in early-stage startups addressing urgent challenges in climate, health, and the future of work. Since 2016, Amplify Capital has supported over 30 companies and relentless founding teams across Canada and the U.S., in pursuit of superior returns and exceptional impact.
About Antares Ventures
Antares Ventures is a specialist deep-tech venture capital fund with a mission to catalyze the scaling of world-class innovation across Asia Growth Markets. We invest globally in early-growth-stage startups developing transformative technologies. Through our proprietary Asia Acceleration Model and backing of regional groups, we are positioned as the ideal partner for ambitious founders ready to transform critical industries in Asia.
About Hard Climate
Hard Climate is a Canadian venture studio dedicated to building and scaling breakthrough climate technologies. Acting as a founder, operator and investor, Hard Climate launches and de-risks transformative technological solutions designed to drive industrial innovation and create lasting positive impact on the environment.
