NOVELTY - The generator has a base structure (14) adapted to be arranged in a body of water i.e. ocean (2), to protect a coastline against incoming waves, where the base structure comprises a foundation (15). An L-shaped duct (3) is associated with the structure for receiving an oscillating water column (4) from the body of water. The column oscillates in response to wave action of the waves. The L-shaped duct forms a part of a coastal protection and ocean wave energy extraction system (1) for capturing energy from the waves through the column and converting the captured energy into electrical energy.    USE - Wave energy generator for a coastal protection system for use with a turbine assembly for extracting electrical energy from oscillating working fluid i.e. air (all claimed).    ADVANTAGE - The generator utilizes a stable and robust offshore base structure to draw two sources of energy such as wave and wind energy, and ensures that an inlet opening of the L-shaped duct is set to face toward the oncoming waves so as to enhance amplification of rise and fall of the ocean waves produced in the oscillating water column within the duct, improve working efficiency of the system and increase amount of energy captured from the ocean waves and electrical outputting rate for wave action. The generator utilizes a main armor to dissipate force of the waves rolling into breakwater to enhance durability of the breakwater and inhibit damage caused by the wave action. The generator makes gravity based structures to eliminate or reduce amount of preparation of a seabed and avoid the need to install foundation piles for the foundation, thus reducing labor intensity and installing time consumption of the generator. The generator ensures that a gravity based oscillating water column duct structure can be formed by water resistant building materials such as steel and concrete so as to avoid environmental hazards. The generator utilizes a permanent magnet generator to be provided with multiple poles for varying amount of electricity produced. The generator makes a combined turbine/generator unit to easily install the generator and reduce maintenance and installation costs of the generator. The generator can be formed with an angled or sloped portion with a flat inner and/or outer surface to ensure modular, robust and efficient construction performance of the duct that includes a flow control segment to inhibit turbulent flow of the oscillating water column flowing within the duct, thus improving energy conversion efficiency of a turbine. The duct utilizes a dynamic resonance control mechanism for dynamically varying i.e. lengthening or shortening, effective length of the duct with high flexibility so as to match resonant frequency of the duct with period of prevailing ocean wave. The generator is simple and efficient to construct and easy to use, and avoids the need of additional complex arrangements and/or mechanisms such as single-way valves or gates to direct the airflow for the turbine in a certain manner. The generator ensures that blades can be interchangeable with different profiles so as to achieve different operating characteristics of the turbine.    DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for a turbine assembly for extracting electrical energy from oscillating working fluid.    DESCRIPTION OF DRAWING(S) - The drawing shows a cross-sectional view of a coastal protection system incorporating an ocean wave energy extraction system.    Coastal protection and ocean wave energy extraction system (1)    Ocean (2)    L-shaped duct (3)    Oscillating water column (4)    Base structure (14)    Foundation (15)