How to Choose the Right Generator Size for Your Building

Generators are major investments, and oversizing or undersizing both have consequences.

Start by listing critical loads: lifts, pumps, lighting, servers, security systems and selected sockets. Decide what must run during an outage and what can wait.

An electrical engineer will calculate total kVA, account for starting currents and diversity, then recommend an appropriate generator size.

Undersized sets struggle to start motors and may trip frequently. Oversized sets run lightly loaded, which can cause wet-stacking and inefficient fuel use.

Consider fuel storage, ventilation, noise control and automatic transfer switches as part of the design.

A correctly sized and well-maintained generator provides reliable backup power without unnecessary operating costs.