How we developed our Plentigrade phase change material

Plentigrade is the high-performance phase change material which powers our thermal batteries.

It’s much more energy dense than water, making our thermal batteries much smaller than the equivalent hot water cylinder.

In the second of our Story of Sunamp video series, CEO and co-founder Andrew Bissell talks through how we made the breakthrough behind Plentigrade, working with the University of Edinburgh.

The idea of storing heat in a phase change material has been around since the 1940s but the existing materials didn’t perform well enough to provide reliable, high flow rate hot water.

We solved this problem, working with the University of Edinburgh, and created a stable phase change material which shows no signs of degradation over the equivalent of 50 years of use. This has allowed us to fundamentally change the way we store heat, whether from the grid or renewable energy sources.

Now, we’ve sold over 25,000 heat batteries containing Plentigrade. We’ve also been recognised with the Royal Society of Chemistry Industry-Academia Prize along with the University of Edinburgh, and the Kings Award for Enterprise in recognition of our innovation. 

Next in the series, we’ll share how our thermal batteries work and how they’re made. If you missed our last video on Sunamp’s vision for a world powered by renewables and thermal storage, catch up here.

Published: 20 July 2023