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Load Balancing in Plain Terms
Every building has a limit on how much electricity it can draw at any one moment. EV chargers are power hungry. Plug in too many at full speed and you go over that limit, which trips the supply.
Load balancing solves this by sharing the power that is spare. It is the hot water idea again. The building only has so much to give, so the system shares it across the cars that are plugged in. No single charger pulls more than the building can safely handle, and the limit is never crossed.
Drivers do not notice any of this. They plug in and charge. The sharing happens quietly in the background.
How It Works
There are three simple parts.
A small controller acts as the brain. It constantly checks how much electricity the whole building is using.
A sensor clips around your main incoming cable and measures that demand in real time.
The chargers themselves are smart. When the controller tells them to ease off, they lower their output. When there is spare power, they speed back up.
When the lifts run, the kettles go on, or the lights come on, the controller sees demand rise and quietly reduces charging power. When that demand drops, charging speeds climb again. This adjusts every few seconds, with nobody lifting a finger.
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The Real Reason It Matters: No Expensive Supply Upgrade
This is where load balancing saves you money.
Without it, every extra charger needs its own slice of power. Ten 7kW chargers would need 70kW of spare capacity. Most buildings do not have that. To get it, you would ask the local electricity network operator, known as the DNO, for a bigger supply. That can mean street works, months of waiting, and a bill from around £5,000 to as much as £100,000 on larger sites.
Load balancing often removes that cost completely. You install the chargers and the system makes your existing supply go round all of them. When more residents or staff go electric, you add more chargers, not a bigger supply.
Will Every Car Still Charge Fully?
Yes. This is the part people worry about, and it is the easiest to answer.
Cars sit plugged in for hours. Residents charge overnight. Staff charge across a full working day. Fleet vans charge between an evening return and a morning start. Even when the power is shared and each car charges a little slower, there is far more time than a full charge needs. You come back to a full battery.
A car that plugs in at 6pm and leaves at 7am has thirteen hours. A modern charger fills most batteries in a fraction of that, even at a reduced rate.
Static Versus Dynamic Load Balancing
There are two kinds, and the difference matters.
Static sharing gives the charging system a fixed slice of power and splits it between the active chargers. It is simple, but it wastes capacity. The slice stays the same even when the rest of the building is quiet and there is power going spare.
Dynamic sharing is smarter. It watches the whole building in real time and gives the chargers whatever is genuinely spare at that moment. Late at night, when little else is running, that can be almost your entire supply. This is what we install, because it gets the most charging out of the power you already have.
Proven Across Every Type of Site
Load balancing is not specific to one kind of building. The principle is the same everywhere, which is why it sits at the heart of how we design every project.
In a 40 flat block in London with only 60A of spare capacity, the raw supply would power a single charger. With dynamic load balancing we installed twelve, and the limit is never exceeded.
In a workplace, staff cars share the spare power across the working day and all reach a full charge by home time.
At a fleet depot, one supply is shared across a yard full of vans overnight, often avoiding a supply upgrade that would have cost tens of thousands of pounds.
