A stand-alone power network is a type of power supply network which is closed and has no active lines coupling it to other parts of the electrical power supply grid. A stand-alone network is markedly smaller than a combined electricity grid and does not usually incorporate high-voltage power lines. For this type of network there are two distinct modes of operation, stand-alone mode and isolated parallel or generator-to-generator operation.

This type of supply network is frequently used for the industrial power supplies of large businesses. When this stand-alone network is connected to a smart grid, it is referred to as a microgrid. This type of grid has three different operating modes: on-grid, off-grid and dual mode. Microgrids will be playing a huge role in the smart grids of tomorrow.

A microgrid features the following benefits:

• Transmission and transformer losses are reduced.
• More independence from major power suppliers.
• Smart grid act as a back-up system.
• Intelligently controlled power supply and consumption thanks to SCADA.
• Power generation using renewable energy sources.
• Optimizing the quality, reliability and sustainability of electricity.