Biogas contains water vapors. Combustion of wet biogas in gas piston engines or turbines leads to corrosion and damage. Therefore, biogas must be demoistured. When cooled, the moisture, contained in the biogas, condenses. The condensate is collected into a trap located in a chiller and discharged through a siphon. This method of removing moisture from biogas is also good because biogas acquires the required temperature.