Renewable energy generators and control

Electricity generation using renewable energy (RE) requires suitable energy converters to deliver power of required quality to consumer loads. Wind, bio, and hydro energy use prime movers, which in turn rotate electric generators that generate electricity to feed different types of loads. In contrast, solar energy converters using photovoltaic panels do not require rotating prime movers as they employ direct energy conversion to produce direct current (DC). But if solar thermal systems are used to produce steam, electricity can be produced through rotating steam turbines. Wind energy drives suitable wind turbines, which in turn drive generators with or without a speed changing gearbox. Bio energy can produce gas to run an engine that drives the generator. An alternative is to use heat in bio energy to produce steam driving a steam turbine coupled to a generator. Hydro energy uses a suitable hydroturbine or operates a pump as a turbine, which in turn rotates a generator.