Microgrid SystemsMany research groups around the world are pioneering various µGrid concepts, also written as microgrids, as an alternative approach for integrating small scale distributed energy resources (DER of < approx. 1 MW) into low-voltage electricity systems. Many other terms are in common use to describe similar concepts, e.g. virtual power plants, minigrids, smart grids, smart distribution networks, embedded generation, distributed or dispersed generation.
Developing an RFP For Distribution Level Microgrids:Traditional approaches to embedding generation at low-voltages focus on minimizing the consequences for safety and grid performance of what are assumed to be a relatively small number of individually interconnected DER, for example implying, that they must instantaneously disconnect in the event of system outage. In other words, permitted local control of devices is very limited, and they can function independently, or islanded, only under special circumstances, e.g. during blackouts after the local system is fully isolated from the macrogrid. By contrast, µGrids would be designed to operate semi-independently, usually operating connected to the macrogrid but separating (islanding) from it, as cost effective or necessary for reliability or other objectives.
Three key potential features of the µGrid are:
- Its design around total system energy requirements
- Its provision of heterogeneous level of power quality and reliability to end-uses
- Its presentation to the macrogrid as a single controlled entity