A microgrid is a small-scale power system, typically serving a local community or group of buildings, that can operate either in isolation from or in parallel with the main electricity grid. Microgrids can provide reliable and resilient power to their users, even in the event of a blackout on the main grid.
Microgrids are typically used to improve the reliability and resilience of electric power supply, but they can also be used to achieve other objectives such as reducing greenhouse gas emissions or increasing the use of renewable energy sources. In many cases, microgrids are designed to operate using a mix of generation sources, including solar PV, wind turbines, combined heat and power (CHP) plants, and conventional diesel generators. This diversity of generation sources helps to ensure that the microgrid can meet its load requirements even when one or more of the individual generation sources is unavailable.
The ability to island – or disconnect from – the main grid is another key characteristic of microgrids. This flexibility allows microgrids to continue operating during widespread blackouts or other emergencies affecting the main grid. In some cases, islanded microgrids may be able to support critical loads – such as hospitals or emergency services – until normal grid operations can be resumed.
Microgrids are often described as “distributed energy resources” (DERs), due to their decentralized nature. This contrasts with traditional centralized electricity systems which rely on large-scale generation plants connected to consumers via an extensive transmission and distribution network. The distributed nature ofmicrogrids means that they are well suited for applications where it is not economically viable to connect to the main grid – such as remote communities or industrial sites located far from existing transmission infrastructure.
There are several different types of microgrid architectures; each one suitable for different applications and user requirements: Centralized Generation Microgrid: A single central generating unit supplies all loads connectedtothemicrogrid.$This$is$suitable$for$applicationswheretherangeofloadsconnectedtothemicrogridismoreorlessconstantovertime(e.$g.$a$factorywithfixedprocess loads). It should be noted that this typeofmicrogridcanstillbeisolatedfromthemaingridifrequired(forexampletoavoidpayingexcessivelyhigh prices for peak electricity). Decentralized Generation Microgrid: Multiple distributed generating units are spread throughout themicrogrid area.$Thisarchitectureispredominantlyusedinapplicationswheredemandfordistributedenergyresourcesisspatiallyheterogeneous(e.$g.$anurbanarea). One advantageofthis approachisthattheuseofmultiplegeneratorscanhelpmitigatetheimpactsofvariabilityinthenumberandtypeofloadson themicrogrid’s operation.#Another#benefit#is#that#it#enables#the#addition#or#subtraction#ofgenerationcapacityasneedschangeovertime.# $ % & ‘()*++,-./0&1*2(*3&4