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HM deals intensely with development of thermal energy storage systems. The innovative plant technology HM-Smart-ICE-Systems connects future technology and ecological as well as economical requirements of the plant operators.

After implemented projects with R134a and R507 as refrigerants in Germany and Belgium, HM installed its first HM-Smart-ICE system using the natural refrigerant propane (R290) in the student restaurant of the Studentenwerk Karlsruhe in a lighthouse project in August 2013. The innovation of the project subsidised with Federal funds: The student restaurant at the Adenauerring is the first European student restaurant not to use any chemical refrigerants anymore – making it the first to meet the statutory requirements applicable as of 2022.

The HM-Smart-ICE flow chart shows three HM process groups

  • HM cold generation
  • HM-Smart-ICE-storage
  • And the consumer

HM-Smart-ICE is an environmentally compatible coolant in the form of a two-phase mixture. The liquid ice principle is based on a mixture of water and an additive, e.g. ethanol or glycol, which lowers the freezing point and therefore produces a mixture of liquid and fine ice particles that can be pumped.

The HM-accumulator principle "night operation" (loading time)

The HM-principle is targeted at cold generation during the night hours – with more beneficial conditions at power costs and more efficient operation due to lower outdoor temperatures.

Day operation (unloading time)

The accumulator provides the cooling capacity that all connected cooling points need during the day – and thus contributes to smoothing the power load at the main consumption times. The added value for the operator: The HM concept can flexibly call the regeneratively produced power for producing HM-Smart-ICE.

The consumer

The application and usage areas of the pioneering environmentally compatible HM technology are diverse – from cooling of foods (e.g. cooling counters and cooling rooms) to transport cold concepts with HM-Smart-ICE, to air conditioning applications with the requirement of smoothing current load peaks in conventional refrigeration technology.

HM-Smart-ICE Tagbetrieb

HM-Smart-ICE Nachtbetrieb