Microgrid Optimization and Sizing

What a microgrid has to balance

Two goals pull against each other: economics (minimise energy and demand costs day to day) and resilience (keep critical load running when the grid fails). Over-build for resilience and payback suffers; under-build and an outage takes the site down. Sizing a microgrid is finding the configuration that satisfies both.

EWISER EStack models the everyday dispatch — solar self-consumption, peak shaving, arbitrage — and the islanding case, where the battery and any generator must carry critical load through a defined outage window, in the same framework.

Grid-tied and islanding modes

In grid-connected mode the microgrid earns its return through the usual value streams. On loss of grid, automatic islanding transfers critical circuits to the battery (and generator, if present) so operations continue. The tool sizes storage energy to the backup duration you specify and power to the critical load's demand.

Where microgrids fit

Facilities with costly downtime — manufacturing, cold storage, data and telecoms, healthcare — value resilience directly. Remote or weak-grid sites use microgrids to cut diesel runtime and fuel logistics. In each case the tool weighs avoided-outage value and fuel savings against capital cost.

Resilience you can put a number on

Resilience is often argued qualitatively, which makes it hard to justify capital. By sizing the battery and any generator to a defined critical load and backup window, the tool turns resilience into concrete quantities — kW of critical demand served and kWh to ride through the outage — that sit beside the everyday savings in the same case.

You can test trade-offs directly: a longer backup window needs more energy; a bigger generator needs more fuel and runtime. Seeing resilience coverage and payback move together is what lets a microgrid be specified deliberately rather than guessed.

Fuel, diesel and weak-grid sites

On remote or weak-grid sites the economics often turn on displaced diesel: solar and storage cut generator runtime, fuel volume and delivery logistics. The tool weighs those avoided fuel costs against capital, so a hybrid microgrid is compared on total cost of energy, not just headline hardware price.

Controls and dispatch priorities

In a microgrid the order of dispatch decides the outcome: serve load from solar first, then the battery, then the grid or a generator, while holding a state-of-charge reserve for resilience. On loss of grid, the controller protects critical circuits and rations energy across the outage.

EWISER EStack models these priorities rather than assuming a perfectly flexible battery, so the sizing reflects how the real controller will behave — and the resilience coverage it reports is one the deployed system can actually meet.

From design to a bankable case

The output is an investment-ready view: resource specification (PV, battery, generator), everyday savings by value stream, resilience coverage, capital cost and the NPV / IRR / payback case — enough to take a microgrid concept to a decision.

Frequently asked questions