Alternative energy generation technologies comprise the use of wind, water, biogas, the sea and possibly geothermal heat to generate electrical energy. All these technologies no matter how micro, definitively replace the use of fossil fuels (coal and oil) to generate electricity. Generators are at the centre of most energy generating systems, the exception being photovoltaic generation. As alternative generation moves offshore and into urban areas, new demands are made of generator technologies. More efficient, robust, low maintenance, modular machines are required for the next generation of wind and water turbines.