NOVELTY - The system has a flexible membrane belt (2) comprising pockets (1) mounted on cylindrical elements or cylinders (3), where the membrane belt is dragged along moving fluid such as river or stream. The cylindrical elements or cylinders are coupled to a mechanical or hydraulic transmission system for driving an electric generator. A flotation structure (11) maintains the cylinders or cylindrical elements at optimum height with respect to the moving fluid. Base structures (6, 8) comprise vertical supports (4) for carrying a moveable element (5).    USE - Self-contained system for use in a sailing boat and a marine craft to generate electric power from a surface fluid flow such as river, stream, tidal flow area and offshore current. Can also be used in an offshore tidal power generation system.    ADVANTAGE - The system utilizes a guide channel structure that comprises opening guide vanes to provide a closed channel for moving the fluid directly under the belt, so as to improve power transfer between the fluid flow and the belt. The support structure is mounted on flotation elements to optimize movement through the water, and the floatation elements are towed behind a marine vessel, so that power can be easily provided to the marine vessel. The cylindrical elements are integrated with a hydraulic transmission, which is linked via a hydraulic connection to an electric power generation unit, so that the power is generated as the vessel moves relative to the fluid. The system is integrated into a hydrodynamic-shaped structure comprising material of low density, so that the structure is positioned directly in an offshore current or rip current, and the system is maintained at optimum depth and attitude in the water.    DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for a method for generating electric power from fluid flow.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic view of a system that comprises a membrane belt, cylindrical elements and support structure.    Pockets (1)    Membrane belt (2)    Cylinders (3)    Vertical support (4)    Moveable elements (5)    Base structures (6, 8)    Flotation structure (11)