Sunamp announced its fourth generation compact thermal batteries for homes on 24 November 2021, at EMEX, the net zero and energy management expo in London1. The company said the Thermino 180 and Thermino 250 models would be introduced in the first half of 20221. No further date for those two sizes has been reported.
The Thermino range is sold in 70, 150, 210 and 300 sizes, described by Sunamp as industry-friendly litres-equivalent measurements that allow direct comparison with the traditional hot water cylinders they replace1. The 180 and 250 sizes sit between those figures. Sunamp said the range uses a new Plentigrade P58 phase change material formulation with greater energy density, and that the batteries are up to four times smaller than equivalent hot water cylinders1. It also said vacuum insulation gives class leading A+ rated models across the full range of sizes1.
Three variants are named. Thermino hp is compatible with heat pumps from Vaillant, Daikin, Kensa and Samsung, with more to come; Thermino e replaces direct cylinders that are primarily electrically heated; and Thermino i replaces indirect hot water tanks with a backup immersion heater1. Sunamp said the batteries can be charged by air source heat pumps, ground source heat pumps, photovoltaics, grid electricity and boilers1. The products were further optimised for heat pumps, including pressure drops up to 70% lower1.
On running costs, Sunamp's chief executive Andrew Bissell said:
"Our analysis based on today's fuel costs has shown that householders can expect to save as much as 1000kWh per year, equivalent to cutting electricity bills by £250 a year at today's prices by using a Thermino e instead of traditional direct hot water cylinder."
Sunamp said the range is the same size and the same price as its third generation product, with improved performance giving up to 12% more hot water capacity1. It said it is active in 17 countries and has sold over 15,000 heat batteries into the European residential market, and that its products made it possible to remove gas boilers from 364 homes in high rise tower blocks in Sunderland1. The company also said it holds A Grade RAL certification, confirming performance with no noticeable degradation to 10,000 cycles, equivalent to over 13 years of daily use at two cycles per day, and that its own testing has confirmed performance to over 40,000 cycles1.
Why it matters for households
A hot water cylinder's footprint is often the constraint on fitting a heat pump, particularly in flats and smaller homes where there is no cupboard or loft space to spare. A store that is up to four times smaller than an equivalent cylinder, in Sunamp's description, changes what is physically possible in those properties, and the 180 and 250 sizes widen the range of capacities available for homes between the smallest and largest units1. Because the store can be charged from a heat pump, solar PV, grid electricity or a boiler, it separates when hot water is drawn from when energy is bought or generated, which is the practical basis of running a hot water supply around off-peak periods or a home's own solar output1. The £250 annual saving figure is Sunamp's own analysis of a Thermino e against a traditional direct electrically heated cylinder at prices at the time, and applies to that comparison rather than to every installation1. Further detail on how these stores work is set out in the site's guide to Sunamp heat batteries, and the wider context for pairing a store with a heat pump is covered in the heat pumps section.
What happens next
Sunamp said the Thermino 180 and Thermino 250 would be introduced in the first half of 20221. The announcement also said it was the first in a series of product announcements to follow over coming weeks, covering space heating, industrial scale systems and new heat pump partnerships1. No dates for those have been reported.