A microgrid is a localised energy system with the capacity to disconnect from the grid and operate as a standalone system. While the majority of the time a microgrid operates while connected to the grid, it is able to switch to its own, on-site generation indefinitely to prevent power outages on the grid disrupting the site.
Within a microgrid, on-site generation can come from solar panels, wind turbines, combined heat and power, generators or other sources of generation. Many microgrids supplement their on-site generation with battery storage, allowing varied electrical generation sources to be better managed and optimised. Increasingly, microgrids also incorporate EV charging, a high-demand technology that needs careful planning in terms of generation and storage to ensure that sufficient power is available within the microgrid.
Many microgrids also manage additional energy vectors in the form of heating and cooling, balancing any electrical heating and cooling technology with other sources such as heat pumps or biomass boilers. Most microgrids span across campus or neighbourhood rather than a single building, allowing electricity, heating, and cooling to be managed across the various buildings of a university, hospital, business centre of residential neighbourhood.
By generating power locally, a microgrid eliminates the losses inherent in most centralised grids, including the national grid and distribution networks. This can save between 8% and 15% of total power generated that would otherwise be wasted through transmission losses. The ability to operate independently also protects an entire site from disruption on the grid by entering into island mode. A degree of independence from the grid can also be important when implementing high-demand technologies such as EV charging, which risk your application being turned down if your DNO feels it risks putting too much stress on your distribution network. With a microgrid, these technologies can operate from on-site generation and batteries without needing additional power from the grid.
An intelligent energy management software is required to manage the energy use on a microgrid. Advanced controllers that monitor both the site as a whole, and the external grid, ensure that the microgrid operates as efficiently as possible. It also helps to reduce external energy costs by purchasing and storing power when prices are low, and relying on on-site generation or stored energy during peak periods.