Half of energy is used as heat and, both across the world and here in the UK, most of that comes from fossil fuels.

But a small business in Hampshire thinks that have the solution to store and decarbonise heat - a heat battery. If successful, the breakthrough could eliminate 4% of global carbon emissions.

On this week's ClimateCast Tom Heap visits the factory producing heat batteries for industry purposes. He speaks to founder James McNaghten about how aluminium and gravel could produce heat, on demand.

Plus he speaks to Dr Iain Staffell, senior lecturer in Sustainable Energy at Imperial College London, about how to scale up the producing of heat batteries and their potential.

Podcast producer: Emma Rae Woodhouse
Field producer: Mickey Carroll