(EP925614-A1)      A method of operating a fuel-cell installation (2) having at least one fuel-cell stack (4) in which at least one working resource for the fuel-cell stack is compressed with a liquid annular compressor (8) and following compression, water is precipitated out of the operating equipment and is then used to cool the fuel-cell stack (4).    The water is utilised to cool the fuel-cell stack after it is flowed through in order to drive the liquid annular compressor (8).    ADVANTAGE -   Reduced number of components installed in fuel cell installation resulting in reduced costs.    (JP2000502834-W)      A method of operating a fuel-cell installation (2) having at least one fuel-cell stack (4) in which at least one working resource for the fuel-cell stack is compressed with a liquid annular compressor (8) and following compression, water is precipitated out of the operating equipment and is then used to cool the fuel-cell stack (4).    The water is utilised to cool the fuel-cell stack after it is flowed through in order to drive the liquid annular compressor (8).    ADVANTAGE -   Reduced number of components installed in fuel cell installation resulting in reduced costs.    (EP925614-B1)      A method of operating a fuel-cell installation (2) having at least one fuel-cell stack (4) in which at least one working resource for the fuel-cell stack is compressed with a liquid annular compressor (8) and following compression, water is precipitated out of the operating equipment and is then used to cool the fuel-cell stack (4).    The water is utilised to cool the fuel-cell stack after it is flowed through in order to drive the liquid annular compressor (8).    ADVANTAGE -   Reduced number of components installed in fuel cell installation resulting in reduced costs.    (US6203935-B1)      A method of operating a fuel-cell installation (2) having at least one fuel-cell stack (4) in which at least one working resource for the fuel-cell stack is compressed with a liquid annular compressor (8) and following compression, water is precipitated out of the operating equipment and is then used to cool the fuel-cell stack (4).    The water is utilised to cool the fuel-cell stack after it is flowed through in order to drive the liquid annular compressor (8).    ADVANTAGE -   Reduced number of components installed in fuel cell installation resulting in reduced costs.    (DE19636908-C2)      A method of operating a fuel-cell installation (2) having at least one fuel-cell stack (4) in which at least one working resource for the fuel-cell stack is compressed with a liquid annular compressor (8) and following compression, water is precipitated out of the operating equipment and is then used to cool the fuel-cell stack (4).    The water is utilised to cool the fuel-cell stack after it is flowed through in order to drive the liquid annular compressor (8).    ADVANTAGE -   Reduced number of components installed in fuel cell installation resulting in reduced costs.