Thermal energy storage involves capturing and storing surplus renewable power that would otherwise be curtailed, and storing it as thermal energy in large-scale facilities like pit storage, abandoned quarries, or mines. This stored heated water can then be dispatched and distributed more widely using heat transmission highways to supply surrounding regions with clean and affordable home heating. Coupling renewable electricity generation with heat networks and thermal storage offers a powerful pathway for the future UK energy system, as it strengthens local energy resilience, lowers system-wide costs, and reduces the need for expensive electricity grid upgrades.

During times of surplus or "waste" electricity production, excess renewable energy can be stored efficiently as thermal energy in large-scale facilities such as large pit storage, abandoned quarries, or mines. This heated water can then be stored for days, weeks, or even months at a time, and can be dispatched and distributed more widely using heat transmission highways to supply surrounding regions with clean and affordable home heating.

The backbone of Hvide Sande's success is a smart, flexible energy system built on renewable generation and long-term thinking. This includes three large wind turbines, a solar park, an electric boiler, a large-scale heat pump, and most importantly, a vast thermal energy storage system. These technologies work together to decouple energy supply from demand, making the most of renewable electricity when it's available, and storing any excess as heat for use when it's needed most.

Across our regions, there are abundant sources of untapped heat that can be harnessed, such as waste incineration, industrial processes, surface water, and geothermal reserves. By coupling these heat sources with renewable electricity generation and thermal energy storage, "Green Energi Havens" can be created to unlock the full potential of British energy, creating a future where nothing goes to waste.

In 2025, over £1 billion was spent shutting down wind turbines due to excess clean electricity production. This excess clean electricity could instead be converted into low-cost heat, stored and distributed to homes through heat highways, a vital sector-coupling solution that makes the UK energy system more efficient. By utilising heat transmission regional-scale infrastructure, also known as Heat Highways, the excess renewable electricity can be transported and used to supply surrounding regions with clean and affordable home heating.