Smart peak shaving: same cars, same energy, a lower peak
Fifteen cars, the same energy for every driver, and four ways to charge them. Plain charging takes the site to 110 kW. Smart scheduling holds it at about 40 kW and still sends every driver away full.
Part of a site’s grid bill depends on its highest peak: one busy quarter-hour can set the demand charge for the whole month. Peak shaving keeps that peak down. Smart peak shaving keeps it down without leaving anyone short.
The example: fifteen electric cars on one site, needing 450 kWh between them, each charging at 11 or 7 kW. Four drivers leave before noon, the others stay until the evening, and three arrive after lunch. The grid connection allows 75 kW.
What makes it smart is knowing when each car leaves and how much energy it needs.
Four ways to charge the same cars
No load balancing
Every car charges at full power the moment it plugs in. Demand rises to about 110 kW, far over the 75 kW connection.
€5,872.90 grid cost a year
Basic peak shaving
Charging is clipped to the 75 kW limit, and the power is split evenly with no idea who leaves when. The drivers who leave early are throttled like everyone else and roll out under-charged: they get 79% of the energy they need.
€4,004.25 grid cost a year
Smart, the same limit
The same 75 kW, with every session scheduled. Pleevi charges the drivers who leave first, first, so every driver leaves full.
€4,004.25 grid cost a year
Smart, a lower peak
Scheduling across each car’s whole stay lets Pleevi hold the peak at about 40 kW, and still send every driver away fully charged.
€2,135.60 grid cost a year
The difference
From 110 to 40 kW is 70 kW off the peak. At €53.39 per kW a year, that is €3,737.30 lower grid costs a year, and every driver still leaves with a full charge: 100% of the early drivers, against 79% with basic peak shaving.
What makes it smart is knowing when each car leaves and how much energy it needs. Basic peak shaving only knows the limit. Smart peak shaving also knows the deadlines, so it can move charging into the hours when the site has room, and keep the peak low day after day. With a battery on site, the battery can take what is left of the peak.
How the numbers work: the grid cost here is the demand charge alone, the peak in kW times €53.39 per kW a year, for one example day. A real site’s peak, tariff and savings differ.
