NOVELTY - The system comprises a first device (2) for biological production of ethanol (4) and for forming carbon dioxide, and a second device (3) for chemical conversion of carbon dioxide (8) to hydrocarbon (5) such as methanol or methane, where the second device is connected downstream to the first device. The first device is connected to the second device by a first connecting line to introduce the carbon dioxide formed in the first device into the second device. A second connecting line connects the second device to the first device.    USE - The system is useful for producing aliphatic alcohols (claimed) such as bioethanol, which is useful as fuel.    ADVANTAGE - The system is capable of producing the aliphatic alcohols in an energy-efficient manner.    DETAILED DESCRIPTION - The system comprises a first device (2) for biological production of ethanol (4) and for forming carbon dioxide, and a second device (3) for chemical conversion of carbon dioxide (8) to hydrocarbon (5) such as methanol or methane, where the second device is connected downstream to the first device. The first device is connected to the second device by a first connecting line to introduce the carbon dioxide formed in the first device into the second device. A second connecting line connects the second device to the first device to introduce the water formed in the second device into the first device. The system further comprises a steam generating device, which is connected to the first device by a third connecting line; and a hydrogen generating device, which is connected to the second device for introducing the hydrogen into the second device. The hydrogen generating device is an electrolysis apparatus. A sixth connecting line introduces the oxygen formed in the steam generating device to the electrolysis device. An INDEPENDENT CLAIM is included for a method for producing aliphatic alcohols.    DESCRIPTION OF DRAWING(S) - The figure shows a schematic view of a system for producing aliphatic alcohols.    Device for biological production of ethanol (2)    Device for chemical conversion of carbon dioxide to hydrocarbon (3)    Ethanol (4)    Hydrocarbon (5)    Carbon dioxide. (8)