What Is a Microgrid?

How does a microgrid work?

Three elements define a microgrid: distributed generation such as solar arrays or other local sources, storage that banks energy for when generation and demand diverge, and a controller that balances both against the site's loads in real time. While grid-connected, the controller decides moment by moment whether to draw utility power, use local generation, charge storage, or export surplus.

When the utility connection is lost, the controller islands the site — disconnecting cleanly and continuing to serve critical loads from local resources. Islanding is what separates a true microgrid from a facility that merely has solar panels or a standby generator.

Why do electrified transport and aviation facilities use microgrids?

Charging fleets of electric vehicles or aircraft concentrates heavy electrical demand at a single address, often beyond what the local utility feeder was built to carry, and utility upgrades come with long lead times. On-site generation and storage let a facility shave those peaks, contract for less utility capacity, and keep operating through outages — a hard requirement for sites that host emergency or medical flights. A microgrid can also make a landing site viable where grid service is weak, because the site brings much of its own energy supply with it.

What separates a microgrid from a backup generator?

A backup generator sits idle until an outage. A microgrid works every day: optimizing when the site buys, stores, and uses energy, integrating renewable generation, and managing peak demand to control costs. Backup power is one of its functions, not its definition.

Can a microgrid run indefinitely without the main grid?

That depends on how its generation and storage are sized against its loads. Sites designed for long independence pair renewable generation with substantial storage, and some add fuel-based generation for extended outages. Most microgrids are built to ride through typical disruptions rather than to operate permanently islanded.

Is a building with solar panels a microgrid?

Not by itself. Solar alone cannot balance supply and demand or run disconnected from the grid. The defining elements are storage and a control system capable of islanding the site while keeping its loads served.

Do microgrids only make sense in remote locations?

No. Urban facilities use them to manage demand charges, host large charging loads without waiting on utility upgrades, and guarantee uptime for critical operations. Remote sites simply lean harder on the independence.