NOVELTY - The system (100) has a fixed pitch turbine (102) rotating in fluid flow (106) i.e. wind, that has varying flow rate. A rotor frame is connectively coupled to the turbine. Stator modules (116, 118) are magnetically coupled to rotor modules (110, 112) and arranged in rings of the stator modules corresponding to rings of the rotor modules. The stator modules incorporate a generating coil to generate alternating electric current responsive to a magnetic field and produce desired magnetically-induced torque that partially controls rotation of the rotor frame.    USE - Tower-mounted electric power generation system i.e. modular electric generator, for generating electric power based on renewable fluid flow or a fluid stream e.g. air, renewable water such as tidal and wave-associated water and geothermally heated water, and wind, for variable speed wind turbines i.e. fixed pitch wind turbines (all claimed), in residential, commercial and industrial sectors. Can also be used for coal and gas-fired power plants, nuclear plants and hydroelectric power stations.    ADVANTAGE - The system allows a peak stress to be reduced, thus achieving larger form factors and system capacities with same cost materials by utilizing a rotor with a vertical axis of rotation, and hence facilitating manufacture of the system in a cost effective manner. The system allows a stator module frame to incorporate a magnetic core so as to enhance performance of the generation coil. The system allows a retrofitted electric power generator structure to include expanded dynamic range with respect to fluid stream flow rates at which a retrofitted system can operate in an efficient and effective manner. The system reduces manufacturing tolerances. The system maximizes power capture for current flow rate and effective flow rate of the fluid stream.    DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for a method for generating electric power.    DESCRIPTION OF DRAWING(S) - The drawing shows a cross-sectional view of an electric generator.    Tower-mounted electric power generation system (100)    Fixed pitch turbine (102)    Fluid flow (106)    Rotor modules (110, 112)    Stator (114)    Stator modules (116, 118)