Guidelines ultrafreezers

Did you know that a single ultrafreezers consume as much energy as two average households?

The many individual freezers consumes a lot of energy. A single -80°C freezer consumes yearly about 6500 kWh (comparable to twice the electricity consumption of an average Flemish family). If we want to drastically reduce energy consumption, to which Ghent University has committed itself in its energy policy plan, we should not only invest in sustainable and fossil-free buildings, but also focus on a rational use of energy-consuming devices, including these ultrafreezers. Therefore, the following guidelines apply:

  • Look for opportunities to buy or use a freezer together with several research groups. This not only saves costs in consumption, but also in purchase and maintenance.
  • We recommend an ultrafreezer with a stirling motor (for instance, Stirling Ultracold Model SU780XLE). Such ultrafreezer is more expensive than the classical model with compression motor, but it use about 30%-25% less electricity. The total cost of an ultafreezer with stirling motor is much lower than the cost of a classical model. As a bonus, ultrafreezers with stirling motor have a refrigerant with very low greenhouse gas potential (GHP) whereas classical ultrafreezers need fluorated refrigerant gasses which have a very high GHP!
  • Let the temperature depend on the type of material. A lot can be stored at -70°C! A freezer at -70°C has 20 to 30% less energy consumption than a freezer at -80°C. The University of Boulder, Colorado compiled a list of 119 biological samples that can be stored at -70°C or warmer. The back-up freezer can be at -50°C. The research group of Plant Biotechnology and Bioinformatics (WE09) has all their ultrafreezers on -70°C.
  • Defrost every ultrafreezer annually. The ice that forms takes up space and increases energy consumption. This saves about 20% in energy consumption.
  • Don’t store unknown or unnecessary products. Take the opportunity of defrosting to put everything in order; this will create space again.
  • For long-term storage, use the central UGent biobank storage.
  • In order to monitor the electricity use, UGent decided to install counters on all individual ultrafreezers to make the costs transparent and to be able to charge them in case of avoidable and excessive consumption.

Central biobanks

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