En kølecontainer kan holde temperaturen i 1-6 timer afhængigt af vejret udenfor, det forlænger antalet af timer som kan dækkes af dieselanlægget, men 11-13 dage er nok alligevel i overkanten.

Men... man kunne laver reefer-points på togene.

https://en.wikipedia.org/wiki/Refrigerated_container#Cryogenic_cooling
'The container is cooled for as long as there is frozen gas available in the system. These have been used in railcars for many years, providing up to 17 days temperature regulation.[4] ... Full-size intermodal containers equipped with these "cryogenic" systems can maintain their temperature for the 30 days needed for sea transport.[4]'