🎧 Can iron overtake lithium-ion for the future of energy storage?

INTERVIEW

TALKING POINTS

• Why long-duration storage is critical for reaching 90%+ renewable penetration

• Inside the physics that make FeX’s Iron Arc reactor work

• Why delivering temperatures up to 900°C unlocks new heavy industry applications

• How iron stacks up against competitors like lithium-ion and hydrogen

• The economic case: competing with diesel and natural gas while lowering carbon costs

• Finding the right markets and use cases to launch and grow

• FeX’s modular, containerized design and its path to scale

• What Canada needs to do to unlock more storage capacity

• Lessons learned from co-founding Siemens Energy Ventures

Listen now: Spotify | Apple Podcasts | Wherever you get podcasts

Mentioned in this episode

• FeX Energy

• Find Hayden on LinkedIn

• Stellar - Tony Seba

• Reinventing Organizations - Frederic Laloux

• Exponential Organizations - Salim Ismail

• The Problem with S-Curves - Arthur Downing

• Data on Canada’s energy storage capacity - CanREA

• Hard Climate

• Siemens Energy Ventures

• The Innovator’s Dilemma - Clay Christensen

DEEP DIVE

🔋 Is iron the future of energy storage?

Renewable energy is being deployed at record levels around the world. In 2024, more than 858 TWh of new generation hit the grid. And clean power now makes up more than 40% of electricity generation.

That’s a huge win for the climate. But without a way to store all that energy, variable renewables like solar and wind can only get us part of the way there.

That’s where energy storage comes in, and it’s potential is larger than ever. All that clean energy needs to be stored so that utilities and energy companies can deliver low-carbon energy around the clock - even when the sun isn’t shining or the wind is blowing.

We’re also seeing demand signals from the grid, where batteries can help meet demand during peak hours (instead of running gas plants) and from new AI data centres that need backup power for high reliability or to relieve pressure on the grid.

Lithium-ion batteries are the most common type of battery energy storage. Their cost has come down rapidly because of manufacturing and tech advances driven by EVs.

But new mediums - like FeX’s iron energy storage - are starting to challenge the incumbents on cost, safety, and duration.

FeX uses oxidization (the same process that causes your car to rust) to release the energy stored in the iron, and deliver energy at extreme temperatures. They’re building it as a modular, cellular system, essentially adding more modules as needed to scale up and provide different output capacities.

In our conversation, Hayden shared how FeX’s iron energy storage has some advantages over lithium-ion batteries and other storage medium.

• Lithium is supply-constrained, as are other rare earths used in the batteries, while iron is one of the most abundant metals with established, diversified supply chains.

• The iron system has a smaller footprint too, as it doesn’t require an electrolyte to move ions between the anode and cathode, giving better energy density.

• FeX also generates heat up to 900°C - something other storage mediums struggle to do.

Finally, iron is stable and holds energy for a long time - potentially even enabling seasonal storage - because the energy is stored chemically and is only released through the chemical oxidation process. If that process doesn’t get started, the energy doesn’t discharge.

Does this mean the end of lithium-ion? Probably not - Hayden acknowledges each technology has it’s use: “We need all of them. We need a lot of players working collaboratively as much as possible to develop different solutions”. But iron has a lot of potential, and it’s unique profile could make it a strong contender for different use cases.

Takeaways

A few things that stuck with me from our conversation:

• Energy storage isn’t new. Hayden pointed out that, at their core, fossil fuels are stored energy from the sun. That energy just took eons to get stored. The energy density and storage ability is part of what made fossil fuels so powerful and ubiquitous, and finding a similar profile in clean energy storage could unlock a lot more abundance.

• Find your niche. FeX Energy’s system has a unique profile, and they’re leveraging those strengths to go after the market opportunities where they can deliver the most value, like remote and off-grid locations. Cost matters, but so does density, cycle-life, response time and other factors.

• Adoption is hard to predict. Growth in renewables is pulling energy storage forward, but the inflection point is hard to predict. Humans are naturally not great with exponential changes. Adoption is unlikely to follow a clean S-Curve.

I hope you enjoy this episode, and let me know what you take away from it.

Justin