NOVELTY - Modules (1) having a water stream driven turbine (17), are submerged in water. The depth from the water level and direction viewed in the longitudinal direction of the turbine to the water flow direction of each module, is controlled by a control mechanism using a ballast weight, a rudder blade (35) rotatably mounted on a horizontal axis and another rudder blade (36) mounted rotatably on a vertical axis.    USE - For producing hydrogen from water.    ADVANTAGE - Produces hydrogen without polluting environment, or producing any harmful products, making use of gulf stream or tidal stream activated by moon phase. Makes use of inexhaustible natural source for driving the turbine. Aligns the module in line with the stream flow by forming the venturi channel, and by the remote controlled rudders. Avoids suspending the module one over the other by controlling the depth of each module. Provides access towers above the water level for accessing the modules for maintenance work, thereby enables maintenance of the module resulting in improving the yield. Prevents sea animal entering the housing by providing the grating in front of the housing. Facilitates storage of produced hydrogen by connecting each module to the storage tower with hydrogen transport lines. Facilitates transfer of hydrogen to tanker/shore.    DETAILED DESCRIPTION - Each module is attached to two sloping or horizontal cables (37,38) connected pivotingly on an anchor host. The electricity generated by a generator (22) driven by the turbine, is supplied to a decomposition apparatus (23) for decomposing the water and generating hydrogen. The generator is spaced radially away from the turbine and drive is transmitted to the generator by a gear transmission. One or more brushes (26) are provided for brushing the grating (24) provided to the front of a housing encircling a flow channel in the form of venturi in which the turbine is installed. The housing is of double walled construction having an inner wall (11) and an outer wall (12). The space between the walls is divided into many chambers by many transverse and longitudinal partitions (27,28). The chambers are connected with each other by an opening (21) in the partitions. An access tower (30) with a top section protruding above the water level is provided to each module. A hydrogen transport line (2) and another line connect each module to a storage tower for supplying the produced hydrogen. A jetty and a transfer facility are provided to transfer to store hydrogen to the tanks or to the shore. The turbine comprises two sets of contra-rotating hollow turbine blades (18,19).    DESCRIPTION OF DRAWING(S) - The figure shows the partially exposed perspective view of module for producing hydrogen from water.    Modules (1)    Hydrogen transport line (2)    Inner wall (11)    Outer wall (12)    Water stream driven turbine (17)    Contra-rotating hollow turbine blades (18,19)    Opening (21)    Generator (22)    Decomposition apparatus (23)    Grating (24)    Brushes (26)    Transverse and longitudinal partitions (27,28)    Access tower (30)    Rudder blades (35,36)    Horizontal cables (37,38)