Seasons greetings from the Sunamp team. See our festive opening hours and emergency cover here.
Seasons greetings from the Sunamp team. See our festive opening hours and emergency cover here.

Increase energy efficiency
Lower energy losses
Unlock renewables
Improve tenant satisfaction

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The deadline looms

Net zero goals, carbon reduction targets, the new tenant satisfaction measures (TSMs), gas boiler ban, meeting regulatory standards and, in Scotland, the EESSH2 milestones mean the need to move away from fossil fuels and swap out gas boilers is more urgent than ever.

Retrofitting heat batteries to decarbonise 


Gentoo Housing was only able to replace gas with renewables in tower blocks thanks to  space-saving Thermino heat batteries.

They managed to complete installations in 364 homes without the need to decant residents and reduced carbon emissions by approximately 420 tonnes or 70%, lowering running costs.

Here’s the interview with Sunamp & Gentoo Group about the ‘Core 364’ gas replacement programme for 7 tower blocks in Sunderland

And here’s why they are a game-changer for social housing

They are energy-efficient and cost-effective
With phase change material Plentigrade P58 at their core, Sunamp heat batteries store thermal energy by using the latent heat of melting & crystallising to achieve extremely high energy density. Here’s the science behind it.
In essence, swapping out an old cylinder for an electrically charged Thermino 210e in a family home could immediately save up to 940 kWh of electricity each year, saving as much as £485

Quick to install and easy to maintain:
Thermino batteries are tried and tested in tower blocks and low-density housing in the UK. The installation is quick and without disruption, which means there’s no need for residents to move out. Here’s how easy it is to replace a hot water cylinder and install the Thermino.
This makes the heat batteries ideal for large-scale retrofit as well as new build projects where space is at a premium.

Engineered to be durable
Sunamp heat batteries offer failsafe performance and no degradation to over 40,000 cycles, which is comparable to over 55 years continuous use, assuming two charging cycles per day.

Ideal where human safety is paramount
Above all else, tenant safety, a key TSM requirement, is addressed as there is no longer any of the risks associated with gas, such as explosion or carbon monoxide, or legionella that flourishes in a hot water tank.


Around 25,000 heat batteries have already been installed by residential customers and social landlords in the UK and in commercial buildings in New York State in the US, and elsewhere around the world.

How does a Sunamp heat battery compare with a traditional hot water cylinder?


Thermino heat batteries are up to x4 smaller than the equivalent hot water cylinder.

No maintenance:

Once installed, Thermino units require no annual servicing.

Minimal disruption:

Thermino units are easy to install with minimum fuss



Instead of having the old boiler in the kitchen, you’ve got this new technology in the cupboard. It’s unobtrusive and it works. And that’s the bottom line.

Nigel Wilson, Chief Executive of housing association Gentoo Group