Stephanie Allchurch, Chair of the Hot Water Association (HWA) and Product Development Manager at Altecnic, discusses how the HWA is working towards decarbonising heating and helping to meet these targets specifically by utilising hot water cylinders as ‘thermal batteries’.
There are currently approximately nine million hot water cylinders installed in homes across England, which accounts for 45% of homes, down from 77% in 2001. This decline has been a result of the rise in installation of combination boilers, over the past two decades. With the UK Government banning all gas and oil boilers from new homes from 2025 in aid of reaching the UK action for net zero by 2050, its clear cylinders and other developing technologies will need to bridge this gap.
As electric heating begins to rise in popularity, and the government targeting 600,000 heat pumps to be installed by 2028, the need for hot water cylinders is also increasing due to these systems needing storage for hot water. Renewable energy inputs require storage systems to harvest and store the sources, hot water storage is the only practical solution to do this.
Hot water cylinders as ‘batteries’
Hot water cylinders have great energy storage potential.
Connected hot water tanks can also deliver a similar service to the grid to that of home battery storage systems. Not only this, but it can also be delivered with a considerably lower environmental footprint from manufacturing from recycled materials.
There are hot water cylinders which operate with conventional gas boilers, whilst at the same time can make use of low carbon electricity whenever there is an over-supply of wind or solar generation relative to demand.
Hot water cylinders have obvious advantages, especially as more UK homes begin to utilise renewable energy sources to heat their home, and we begin to see an increase in multi-outlet demand. However, there are also some challenges, particularly in the installation of hot water cylinders in modern homes as they require additional space. These issues can be tackled through the usage of more compact stores and installing in lofts and garages.
A solution for all
For consumers, replacing an old hot water cylinder with a modern, well-insulated cylinder, coupled with smart controls, provides an opportunity to use low cost, or even negatively priced electricity alongside their existing heating equipment. There are also additional benefits, such as ease of control, enhanced system boiler efficiency and future retrofit options for heat pumps or hydrogen ready gas boilers.
