Unlocking the smart grid potential of the UK's domestic hot water tanks


As part of the UK Government’s latest drive for energy innovation, market leading hot water cylinder manufacturer Heatrae Sadia has joined forces with smart energy company Levelise to review the feasibility of using existing and new domestic hot water cylinders to offer smart grid services. This project is being undertaken as part of the BEIS Domestic Demand Side Response programme.


The Ubiquitous Storage Empowering Response (USER) project will seek to unlock the prosumer role in the domestic sector by means of AI-led hot water tanks. Currently, there are 9 million hot water tanks, which if appropriately managed, represent a 27 GW demand response opportunity. Through addition of communications infrastructure, sensor technology, AI-led optimisation services and consumer settlement infrastructure, these hot water cylinders could be cost-effectively turned into flexible assets capable of providing demand response whilst also opening peer-to-peer energy trading opportunities. The hot water tank can be heated using the electrical immersion heater during periods of excess supply on the national, district or local electricity system, and release the heat when required. Through aggregation and optimisation of domestic storage assets, flexibility services could be provided by hot water systems, generating revenue for the consumer and delivering benefit for the energy system.

The development of home battery systems has been an important area of innovation particularly when deployed alongside Solar PV. Smart hot water storage can complement this technology by working in conjunction with the domestic battery system, providing additional flexibility and generating additional revenue for the household.

Phase 1 of the project, which will run from May to July 2018, will assess and develop the technology integration and market frameworks for realising their potential, not only for demand side response to improve system-wide efficiency, but also for peer-to-peer trading to increase the penetration of intermittent renewables. It will look to understand consumer usage patterns and to design a system which does not negatively impact the consumer experience of hot water, and synergy opportunities between hot water tanks and stationary batteries will also be explored seeking to boost their impact. 

If successful, the project will then move on to Phase 2 which will look to demonstrate the viability of the technology system and commercial model in a field trial. At this point, the project team will require further partners to host the field trial. 

Heatrae Sadia is the UK's leading manufacturer of hot water storage and generation equipment and the company has a long history of pioneering innovation and low carbon solutions. Most recently, Heatrae Sadia has launched the award winning ‘’Megaflo Eco Solar PV Ready Cylinder’’, that harnesses surplus solar electricity produced by solar panels on a home to generate hot water, saving energy and reducing utility bills.

Levelise is a technology start-up founded in March 2017 with the aim of commercialising home energy management technology developed over the previous 5 years. Based in state of the art facilities on the Oxford Science Park, Levelise provides energy management services that enable homeowners with solar and battery systems to earn additional income from their systems.