It is disclosed a system for producing methanol/methane, said system comprising an electrolysis section (1) producing hydrogen and oxygen from the cleaving of water molecules, and said system further comprising a closed cultivation/breeding container/pond (5) for aquatic organisms creating CO2 through their metabolism to be liberated into the water surrounding said organisms forming CO2-rich water, said CO2-rich water being transported to a CO2-liberating section forming gaseous CO2 and CO2-poor water, said liberated gaseous CO2 being transported to a reactor (6,6′) and being combined with said hydrogen from said electrolysis plant (1) for creating methanol and/or methane as an end product, said methanol/methane being isolated and exited from said system.