Power in a building is a fixed budget that is mostly already spent. EV charging has to live on what remains — and that remainder runs out faster than anyone expects.
Your building already has a power budget
Every building is built with a set electrical service — a ceiling on how much power it can pull at once. Elevators, lighting, HVAC, pumps, life-safety systems, and the units themselves all draw from it. By the time you ask about charging, most of that budget is already committed. EV charging competes for the headroom that is left.
One charger fits. Many compete.
A single charger usually slips into the existing headroom without trouble. Add a few more and the math tightens. At some point the building hits its ceiling, and the next charger no longer fits without a bigger service — a transformer, a panel, sometimes a utility upgrade. That threshold is the entire question, and it arrives sooner than most boards assume.
A building comfortably added four chargers off spare capacity. The fifth request would have pushed the service past its limit. The fix was not another charger — it was a capacity upgrade priced in the hundreds of thousands. The first four owners paid for a unit. The fifth was being asked to pay for the building.
Demand management and load sharing
Here is the good news: cars do not all charge at full power at the same time. Most sit plugged in overnight needing only a partial top-up. Demand management and load sharing use that fact — software that spreads the available power across many chargers, slowing each slightly so the building serves far more vehicles than a naive one-circuit-per-car approach ever could.
- Load sharing lets a group of chargers split a shared circuit intelligently instead of each demanding its own maximum.
- Demand management watches the whole building and throttles charging when other systems peak, protecting the service.
- Together they can multiply how many EVs a building serves without a major upgrade — often the difference between "we're full" and "we have room to grow."
Plan for adoption, not for today
The building that wires for one charger solves this month. The building that plans for adoption solves the decade. EV ownership in a building rarely stays flat — one becomes three becomes a waitlist. Designing capacity and controls for where demand is heading, rather than where it is, is what keeps the building from rebuilding its electrical system twice.
The question is rarely whether one charger can be installed. It is whether the building can support many.