Tank ventilation and cooling system for hybrid vehicles

A method for operating a deaeration and cooling system, the method comprising:

• providing an absorption refrigerator for cooling fuel in a fuel tank, the absorption refrigerator comprising a burner, an evaporator and an exhaust-gas heat exchanger;
• and
• selecting a source of thermal energy for the absorption refrigerator based on an state of an internal combustion engine, wherein the selecting includes selecting the use of thermal energy from the combustion of gaseous fuel when the internal combustion engine is in a stopped state, or selecting the use of thermal energy from waste heat of the internal combustion engine in addition to the use of thermal energy from the combustion of gaseous fuel during the operation of the internal combustion engine, with a preference of selecting the use of waste heat.