A method of maintaining a space in a means of transport, such as a vehicle, at a desired temperature. The vehicle is provided with a storage tank containing a medium having a suitable temperature. According to the invention the storage tank is part of the transport means, the storage tank possesses an inlet opening for increasing the capacity for maintaining the space at the desired temperature, and is thus achieved; i) by feeding through the inlet opening a regenerating medium-comprising liquid and, after heat exchange between the regenerating medium and the medium, discharging the regenerating medium-comprising liquid; or ii) by via the inlet opening replacing the medium in the storage tank comprising liquid with medium-comprising liquid having a greater capacity of maintaining the space at the desired temperature.