The Technology behind EnergiVault®

EnergiVault® has developed and patented a unique thermal phase change battery technology to provide Cold Thermal Energy Storage (CTES) solutions. Initially focusing on decarbonising chilled supply chain (food manufacturing, distribution, food retail), the technology can be applied across industrial refrigeration, air-conditioning and refrigerated transport systems.

The EnergiVault technology is a thermal storage system providing cooling support to existing or new working fluid based cooling systems. It can be sized for short or long daily charging and can deliver very high cooling rates many times the charge rate. For example, a 1MWht thermal store can be charged over 16 hours using a small charger of c. 65kWt and discharged at a cooling rate of 1MW in an hour, or 500kW for 2 hours. The EnergiVault technology comprises the EnergiVault Crystalliser module comprising a condensing unit sized for the charge rate, an ice slurry crystalliser, charging pump and control module. In addition to the Crystalliser module is the EnergiVault thermal store or battery module which comprises the thermal storage vessel or vessels, charge quantification device, cooling pump and 3-way valve to control the delivery of cooling.

Modes of operation

The cooling support is provided once the controller sees the returning working fluid deviating from the set point, modulating a diverting valve to allow the working fluid to be cooled by the EnergiVault Thermal bank.

More sophisticated modes of operation including dynamic charging based on energy price signals, with additional cooling support available when primary chillers are switched off or their capacity is exceeded.

As the proportion of untimetabled renewable energy being fed into the National Grid increases, the problem of balancing electrical supply and demand becomes more acute. This occurrence has negative implications for energy sustainability, affordability, and security.


O-Hx - Example EnergiVault Discharge Rates

EnergiVault Thermal Energy Storage (TES) is the smartest cooling technology available, complementing and supporting the ever increasing uptake of unpredictable renewables.



How does EnergiVault unlock value?

Enhanced Energy Recovery

  • Heat at c. 100°C (high grade) and 40°C (low grade) is available
  • Suitable for DHW, space heating & many process heat needs
  • Adjust EV charger operation (and operation of chiller and/or electric heating) to maximise self-consumption of on-site generation (Solar, wind, CHP, etc)

Time-of-Use Optimisation

  • Maximise energy cost savings using TOU tariffs & network charges, by charging EnergiVault at off peak times
  • Reduce contracted grid capacity charges, but reducing peak load
  • Grid flexibility contracts through aggregators allow access to payments e.g. absorbing renewable power

Chiller Efficiency Optimisation

  • Reduce part load inefficiency with EnergiVault support
  • Reduce capex of peak chillers with EnergiVault support
  • Reduce/ avoid unnecessary O&M costs by running chillers at full load
  • Option to provide weather and/or load compensation to chilled circuits

Integrated Energy Insights

  • Monitor facility electrical, heat and cooling demand and generation
  • Track energy usage trends versus operational and external factors to provide alerts for unexpected demand patterns
  • Identify inefficient operation
  • Provide customised web front end

Maximise Value of Local Zero/Low Carbon Generation

Maximise self consumption • Reduce import costs • Reduce CO2 footprint


What is Unique

The effectiveness of thermal energy storage is ALWAYS dependant on the volume and speed of energy transfer between the stored energy (bank), and its recipient

EnergiVault is connected to existing secondary cooling circuits without a conventional heat exchanger, using the same working fluid throughout.

The EnergiVault thermal battery acts as an “organic” heat exchanger, with working fluid entering the thermal battery being “chilled” and fluid drawn off the base of the battery.

The heat exchange surface area within the battery (i.e.the micro sized crystals of the working fluid) increases as the charge increases.

The ”organic” heat exchanger has vast surface area, ever increasing in size as morespherical ice particles are created.

This enables support of massive cooling loads.


How Thermal Exchange Occurs conventionally?

Thermal exchange occurs through a “heat exchanger” and usually takes the form of :
Tube in tube – Where contra-flowing fluids exchange their thermal energy through the wall of concentric pipes, usually in a coiled form.
Shell and Tube – Where thermal exchange is accomplished through a bundle of enclosed tubes.
Plate – Where dissimilar fluids occupy both sides of a matrix of plates.

Conventional Heat Exchangers:

  • Conventional heat exchangers are all limited by their physical size as this depicts how much heat exchange surface is available to the dissimilar temperature fluids, passing either side of the heat exchange surface. For compactness, the plate heat exchanger is the obvious choice, but often NOT when one or both fluids carry particulate contamination, thus with the potential for blockage.
  • The tube in tube heat exchanger, although significantly larger in size, also can present difficulties in cleaning, should fowling occur.
  • Shell and tube heat exchanger, although smaller in size than its tube-in-tube counterpart, still has limitations.
  • In ALL cases, the heat-transfer capability is limited by the available heat transfer surface.

Organic Heat Exchangers:

  • The Organic Heat Exchanger eliminates ALL issues with heat transfer processes because the heat transfer surface increases proportionately with the volume of energy in storage.
  • The Organic Heat Exchanger is so named because it uses the slight film of organic material surrounding each stored energy-rich particle as the only barrier to heat transfer.
  • The more particles stored, the higher the heat transfer surface available.
  • By example, an EnergiVault battery with a full charge capacity of 1MWh thermal, could support a cooling load of 6MW for 10 minutes duration.
  • Similarly, the same EnergiVault could discharge at 100KW for a duration of 10 hours.
  • This level of flexibility is unavailable from any other heat exchanger type.


Decarbonising Cooling & Heating for Industrial, Commercial & Multi-Residential.


Get Ready for the Net Zero Future!



Organic Heat Exchangers (O-Hx) is the home of the patented “EnergiVault” technology, capable of storing and delivering vast amounts of thermal energy on demand to drive down the cost of cooling and provide infinitely scalable energy storage. 


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147 - 149 Victoria Road East
United Kingdom

01253 829828