Battery storage and EPC ratings are now more closely connected following changes introduced under RdSAP 10. Domestic battery systems — typically installed alongside solar photovoltaic (PV) panels — are now recorded as part of the EPC assessment. This allows assessors to capture a fuller picture of your home’s energy features.

However, even though battery storage is included in the assessment, it usually has little to no impact on the actual EPC rating. This is because EPCs are based on modelled energy costs rather than actual usage or carbon savings. Unless a battery is specifically set up to reduce electricity demand during peak hours, it does not significantly lower the estimated energy cost used in the rating calculation.

Most battery systems store excess solar energy for later use, which can be very effective in practice. But because they don’t always show a measurable cost saving in the EPC model, they rarely improve the rating band.

That said, including battery storage in the EPC provides transparency and may become more relevant in future. As software improves and time-of-use tariffs become more common, smarter battery systems could eventually play a more influential role in determining a property’s energy performance rating meaning there is a better link between battery storage and EPC ratings.