How a Heat Battery Works

Energy for your heat battery can come from a number of sources:







Principles of the Heat Battery

Works like a hand warmer...

Click to release the heat...

Recharge in hot water...

How a Heat Battery Works

Stage 01 - Charging the Heat Battery

Energy, from any source, can be added to the battery to charge it.

Be it electricity from the national grid over night, or solar photo voltaic panels during the day, a gas or biomass boiler, a wind-turbine, even an air source pump.

Just like boiling the pocket hand warmer in water, this energy added to the battery changes the state of the Phase Change Material (PCM), shown here in green.

In absorbing the energy as heat, the PCM changes state and stores it, until it is needed.

Like the hand warmer, that won’t radiate its heat until the metal is clicked, the heat battery won’t give up its heat until you pass water through it.

How a Heat Battery Works

Stage 02 - Discharging the Heat Battery

Cold water in - hot water out.

Connecting your heat battery to the mains water pipe, and then opening a tap or turning on a shower enables pressurised cold water to pass through the high power heat exchanger in the battery.

As soon as the battery has some charge, it can discharge hot water. Once fully charged, a size 9 unit will give you 300 litres of water at 40°C, enough for oodles of relaxing showers.

The PCM in the battery, transfers its heat to the water via the heat exchanger, the water heats to 55°C very quickly.

This is a little too hot for domestic use, so we fit a device to bring the temperature down to a more manageable temperature.

The PCM will cool with this heat transfer and change back to its cool state.The battery can be charged whist hot water is being drawn off.

They have been tested over 40,000 cycles of charging and discharging, without a single failure or any degradation to the PCM. That’s over 50 years of daily use.

Available in a range of sizes to suit your requirements.

Size 3

80L tank equivalent. For small businesses and annex apartments.

Size 6

150L tank equivalent. For a 2/3 bedroom property, 1-2 bathrooms or a business with a shower.

Size 9

210L tank equivalent. For a 3/4 bedroom property, 2-3 bathrooms or a larger business with showers.

Size 12

280L tank equivalent. For larger properties with lots of bedrooms and bathrooms or big business and sports pavilions.

Further information

Two YouTube videos for a deep-dive into Heat Batteries

Running Time: 17 minutes 56 seconds

In this video, Orkney resident, Jonathan Porterfield describes how he uses a Heat Battery to provide hot water in his home using Solar PV as an energy source. He then goes on to answer a few questions sent to him by viewers of his previous videos.

Running Time: 11 minutes 56 seconds

In this video, Energy Storage News visits the Sunamp headquarters in East Lothian to talk to Andrew Bissell, COE of Sunamp and Professor Colin Pulham of the University of Edinburgh, about the workings and efficiencies of a Heat Battery.