Question to the Department for Energy Security & Net Zero:

To ask the Secretary of State for Energy Security and Net Zero, what assessment his Department has made of the potential contribution of heat batteries to balancing grid demand during peak energy usage periods.

Heat batteries are a promising low-carbon heating technology because they utilise time-of-use tariffs and do not require outside space. However, they are less efficient than heat pumps and therefore use more energy to meet the same heating demand. Although they can be charged at off-peak times, if not sized or used correctly, heat batteries could add to peak demand on the electricity network and increase bills for property owners. The Department is exploring, through studies like the Homes for Net Zero Trial, the role heat batteries could play in the future.