Refrigeration system for cooling a container

The present disclosure relates to a refrigeration system for cooling the interior of a mobile refrigerated space, for example a refrigerated container, comprising two speed-controlled compressors, which can be operated in parallel as a single stage or one after the other as two stages by one controllable bypass line per compressor and a controllable valve device between the pressure side and the suction side of each compressor. The valve devices receive signals from a controller having algorithms, into which the usage temperature and ambient temperature are fed as a target value or measured value. The most energy-efficient operating modes and the rotational speeds of the compressors result from the requirements profile of the container refrigeration.