The Next Frontier of Electrification? Industrial Heat | Ep271: James Macnaghten

Around the world, factories making food, drink, pharmaceuticals and other everyday products rely on steam, often produced by fossil-fuel boilers. James Macnaghten, founder and CEO of Caldera, is betting that thermal batteries can provide a cheaper and more flexible alternative that stores electricity as heat, and delivers steam on demand.

This week on Cleaning Up, Bryony Worthington visits Caldera's factory to see how it makes its heat batteries: combining recycled aluminium and iron ore pellets to create a long-lasting, efficient heat store. The technology is designed for industrial processes up to 200°C, which James sees as a major opportunity for electrification.

They discuss how thermal storage can help factories manage peaks in demand, use electricity when it is cheap or abundant, and reduce pressure on congested grids. They also explore Caldera's plans to scale, its journey from domestic heating to industry, and why James believes a more pragmatic approach to electrification is needed.

Topics discussed in this episode:

The hidden opportunity in industrial heat

How Caldera's heat batteries work

Why steam still matters

Heat pumps and thermal storage

Managing industrial demand spikes

Turning surplus power into heat

Scaling a UK climate-tech company

The case for pragmatic electrification