Government is underplaying potential of hot water storage

A new report from the Hot Water Association (HWA) is highlighting the government’s failure to recognise the role hot water cylinders can play in decarbonising heat.

The HWA’s ‘No place like home’ report claims that there are a number of gaps in government policy that negatively affect the UK’s hot water storage infrastructure. While much of its focus is on the heat source, such as boilers and heat pumps, the report says there is not enough emphasis on storage solutions, which are a vital part of a low carbon heating system.

Launched in the wake of the Heat and Buildings Strategy, the HWA report comes with a stark warning for government to step up its efforts to decarbonise heating, or risk losing out on untapped energy storage.

Less than 45% of homes in England currently have a hot water cylinder installed, down from 77% in 2001, largely due to the boom in combi boilers, which don’t require storage.

“However, this still equates to 70GWh of untapped energy storage – around 7 times the capacity of the UK’s largest pumped hydro power facility, Dinorwig, in Wales,” says Isaac Occhipinti, director of external affairs. “HWA believes that homeowners with a hot water cylinder should be educated on its full potential and encouraged to retain it in order to future proof their heating system and maximise the UK’s energy storage potential.”

Storage systems are essential partners to any renewable energy input, the report says, so the harvested heat can be stored for later use.

“Hot water storage is the only practical solution to turning the energy into something useful and banking it for when it needs to be used,” added Occhipinti.

“The energy storage potential associated with the UK’s installed capacity of domestic hot water cylinders is comparable to our entire fleet of pumped-hydro-electric storage and with just a fraction of this resource, it would be possible to absorb the largest surpluses of renewable power that arise from offshore wind and solar PV.

“Government must do more to educate homeowners, local authorities and social landlords on the benefits and potential of hot water storage, and homeowners should be able to access incentives if they wish to replace their hot water cylinder.

“If we do not invest in this untapped asset then it will become more expensive to upgrade homes to become ready for Net Zero. We also will not be able to take advantage of the current grid balancing potential of millions of hot water stores.”

‘No place like home’- the HWA’s full report on the potential of Hot Water Storage is available to download here.