Microgrids and Distributed Energy Future

Microgrid appears with the development of distributed generations (DGs) and distributed renewable energy resources. It is usually located in low voltage networks and connected to the power grid through switches. In remote or isolated areas, microgrid is an alternative way of power supply instead of installing expensive long-distance transmission lines. A microgrid combines DGs, loads, distributed energy storages, and cogenerations to form a mini power system. The system could be operated as grid-connected mode or islanded mode. The autonomous operation is one of the features of microgrid. Distributed renewable energy resources and small-scale clean energy generating units are the major generation resources in microgrids. The development of microgrids and distributed clean energy generations will be one of the solutions to carbon emissions and global warming. Microgrid is a transition step from conventional power systems to smart grid. The demand management and generation control in a microgrid could significantly improve energy efficiency and system operation. In this chapter, the concept and development of microgrid are introduced. The challenges and operation issues are discussed for microgrids. In the end, the operating microgrids all over the world are introduced.