A typical ULT freezer consumes between 9 and 20 kWh/day, which translates to 3 to 7 MWh/year. According to Loja Luz by Selectra, the annual energy consumption of an apartment in Portugal with 1 kitchen, 1 living room, 1 bedroom, and 1 bathroom is 3777 kWh. According to Pordata, the annual domestic energy consumption by an individual in Portugal is around 1.1 MWh.
Reference: Farley and McTear
One ultra-low temperature freezer set at -80 °C spends as much energy as a small family apartment. ¹
How to save energy?
Consider increasing the working temperature of your ultra-low temperature freezer.
Why?
Ultra-low temperature freezers used to be set at -70 °C.
If you ask senior researchers, they will probably remember. Last decades, manufacturers started to offer more robust units, which were able to maintain -80 °C and then this temperature started to be the norm.
By increasing the temperature from -80 °C to – 70 °C you can save 30% of energy. ²
Many laboratories around the world, including researchers at the i3S-University of Porto and at the Biomedical Centre at LMU, are now increasing the temperature of their freezers from -80 °C to – 70 °C and are happy with the outcome.
Many biological samples are stable at -70 °C.
In this database, scientists from the University of Colorado Boulder, California Davis, Riverside, and San Diego share which sample types they are storing at -70 °C or warmer.
Ultra-low temperature freezers: At which temperature?
After the fume hood and biological safety cabinet, this is probably the most energy-costly piece of equipment you use.
Energy & Water
