The Hot Water Association (HWA) has launched its new paper, ‘Connected Homes – Banking Energy with Hot Water Storage’, to highlight the vital but often overlooked role of hot water storage in delivering the UK’s net zero ambitions. The event, held at the historic One Great George Street, Westminster, as part of Net Zero Week 2025, brought together policymakers, industry leaders and representatives from the Department for Energy Security and Net Zero (DESNZ).
Adrian Waddelove, Manager of the HWA, opened the briefing by stressing that the journey to net zero demands a whole-system approach – one that recognises the essential contribution of hot water storage, not only for household comfort but as a practical tool for grid flexibility. He reminded attendees that hot water cylinders, so often hidden away in cupboards, can play a major part in cutting carbon, saving households money and balancing the electricity grid.
“It became clear today that hot water is an integral part of the net zero pathway, both from the consumer’s perspective and for the electricity system,” Waddelove said. “Our industry has argued that it is a national scandal that taxpayers’ money is spent on curtailment payments to turn off renewable generation, instead of banking surplus energy for later use. Hot water storage can help end that waste, and save households money at the same time.”
The HWA called for hot water to be recognised distinctly from space heating, noting that while space heating is largely seasonal, hot water is needed all year round. It therefore holds untapped potential to absorb surplus renewable electricity even in the warmer months.
Catherine Atkinson, MP for Derby North, addressed the audience, reaffirming the government’s commitment to becoming an energy superpower while supporting skilled jobs and industrial growth. She said: “The shift to net zero can deliver real benefits to people’s everyday lives. Smarter use of hot water storage can help lower costs, cut our reliance on fossil fuels and open up new opportunities for skilled local jobs and apprenticeships. This is a simple but powerful example of how clean energy solutions can support homes, local businesses and bring down bills – all whilst strengthening our economy.”
Incoming HWA Chair Stuart Elsy highlighted that the UK’s nine million existing hot water cylinders represent ‘low-hanging fruit’ for storing cheap, clean energy. This could be equivalent in capacity to home batteries but at a fraction of the cost. He stressed that hot water storage can unlock up to 35 GWh of flexible daily capacity – enough to cover around 5% of the nation’s daily electricity demand – with minimum upfront investment. And it would not require the use of rare earth metals.
Stephanie Allchurch, outgoing HWA Chair and Product Development Manager at Altecnic, underscored the practical and immediate opportunities to connect existing systems to smart controls, helping households shift demand and benefit from time-of-use tariffs. “Consumers could save up to £200 per year while helping the grid make the most of renewable generation,” she said.
The ‘Connected Homes’ paper sets out clear recommendations for policymakers, including treating hot water storage as a strategic asset in the transition to net zero, incentivising smart controls and ensuring building standards and grant schemes reflect its year-round value.
“The case for action is compelling,” added Waddelove. “Hot water cylinders have been quietly delivering comfort and reliability for decades. Now they can also help deliver our net zero future. It is time they were brought back into the spotlight.”
For more information visit www.hotwaterassociation.co.uk
