Microfluidic expansion valve to increase the energy efficiency of small and compact refrigerators (Mikroexpans)

In the joint project, the first electronic micro expansion valve specially adapted to the small cooling capacities of household refrigerators and freezers (approx. 30-200W) was developed. Tests with functional models in conventional refrigerators and freezers have shown that energy savings of about 4% are achievable compared to the capillary tube. Extrapolated to the existing 72 million household refrigerators and freezers in Germany, this corresponds to an estimated electricity saving potential of 400,000 MWh per year or the annual electricity consumption of 250,000 people.

Since the first domestic refrigerators emerged in the 1920s, a thin, several meters long capillary tube is typically used as a throttle valve in household refrigerators and freezers to expand the refrigerant. Adjustable valves instead of the capillary tube for precise adjustment of the cooling capacity, so-called expansion valves, are currently only applied in larger refrigeration systems due to the technical challenges with small cooling capacities.

In the joint project, the first electronic micro expansion valve specially adapted to the small cooling capacities of household refrigerators and freezers (approx. 30-200W) was developed.

Tests with functional models in conventional refrigerators and freezers have shown that energy savings of about 4% are achievable compared to the capillary tube. Extrapolated to the existing 72 million household refrigerators and freezers in Germany, this corresponds to an estimated electricity saving potential of 400,000 MWh per year or the annual electricity consumption of 250,000 people.