A European ‘super refrigerator’ for the International Space Station

The MELFI freezer has a maximum mass of around 800 kg, including spares and up to 100 kg cold payload. Total stowage volume is 300 litres, in four compartments, called dewars, which can be independently temperature-controlled so that multiple mission configurations are possible. At least one dewar is maintained in -80°C mode.

Single whole sample specimens or fluid samples (such as blood) of up to 500 ml can be stored, and cell culture or dissection tissue samples of up to 10 ml. Freezing time varies with the size of the specimen: typical times (at temperatures of +23°C to -68°C in zero-gravity conditions are of the order of 18–25 minutes for 2 ml samples, 29–41 minutes for 5 ml samples, 44–56 minutes for 10 ml samples, 165 minutes for 100 ml samples, and 460 minutes for 500 ml samples.

MELFI can be controlled either in remote mode or in manual local mode.

Comprising several MELFI units, the system is designed for an operational lifetime of 10 years.