We need to talk about heat flexibility

A new report by Thermal Storage UK highlights the potential of heat flexibility to reduce electricity demand, bring down bills and progress the energy transition. The trade body’s founding director Tom Lowe shares some of its key conclusions and recommendations.

In an increasingly electrified world, heat flexibility is at the heart of making the best use of renewable power generation, running our electricity networks efficiently and ensuring our heating systems warm our buildings.

The UK is building renewables to diversify the generation mix, improve energy security and decarbonise. On the demand side, the UK is electrifying transport and heat to move away from fossil fuels like gas. These products increase peak demand on the electricity system, with National Grid Electricity System Operator (ESO) expecting electricity demand to double by 2050. The more that flexibility is utilised on the demand side, the less the UK needs to spend on network infrastructure, curtailing renewables and using the capacity market for fossil gas power plants.

There are multiple ways to provide flexibility in heating. One option is to  use smart thermal storage, working with or instead of heat pumps, to shift heating demand. Smart thermal stores produced by British companies such as Sunamp, tepeo and Caldera  can consume electricity at times of lower wholesale prices, which are increasingly at times of higher renewable generation.

Thermal Storage UK has published a new report on the potential for heat flexibility by 2030. We worked with consultants LCP Delta who estimated that, by 2030, the UK could use smart thermal storage in 2.4 million homes to reduce peak electricity demand on the coldest day of the year by 1.6GW.

This peak demand reduction from smart thermal storage could increase to 4.1GW if the benefits of flexibility to electricity networks were reflected in pricing. With the right reforms to the power market to recognise the value of this flexibility to the electricity networks, we expect smart thermal storage to further flatten demand.

We offer 16 recommendations in the report, including rearranging the wholesale market to decouple renewables from fossil gas generation, requiring retailers to offer time of use tariffs and training more UK heating engineers for the transition. Heat flexibility policy is an underdeveloped area of thinking in the energy sector. We recommend that further work is done to refine the analysis and to consider the interaction with potential power market reform options. We also welcome feedback on any or all of the assumptions we have made.

We are confident that the future of heat requires designing low carbon electric heating to provide heat to buildings and flexibility to the power system. This requires drawing together a wide range of people with expertise in heating systems, buildings and the electricity sector. It means using the skills of heating engineers and the skills of electricity system designers. It means listening to those who work on heating systems and power systems day after day.

We sometimes hear talk of silver bullets in energy. Silver bullets in folklore ward off werewolves. The changes brought about by climate change are too real to rely on folklore remedies. Sometimes the real world is less dramatic than folklore. We have the technical solutions to use renewable electricity to heat buildings. We now need to ensure that lots of people work together to design effective power markets, develop time of use electricity tariffs and install flexible heating products.