EV Charging in Car Parks Lab
Plan the chargers for a car park: how many, which mix of AC and DC, and what they do to the transformer. Compare no load management, a static cap and dynamic load management that fills the spare capacity left by the building, then check the feeder and the authority rules for DEWA, New Zealand and Australia.
How to use: enter the bays, the share with chargers and the charger mix. Pick the building type so the arrival pattern and building load match. Tap i on any input for help.
1. Inputs
2. Car park and charging day
Chargers on the car park plan, a 3D deck and the 24 hour load against the transformer.
3. Checks
4. Charger schedule
Indicative cable sizes for short runs on cable tray. Size every circuit for its own route.
5. Load management compared
Same car park and the same day, three strategies.
6. How it works
Charger mix
Most cars in residential and office car parks stay for hours, so 7.4 kW single phase or 11 to 22 kW three phase AC chargers are enough. DC chargers suit short stays (malls, fuel stations, fleet depots). A few DC chargers can need more capacity than a whole floor of AC chargers.
Load management
Without management every charger can draw full power at the same time, and the car park is sized for that. A static cap limits the EV board to a fixed kW and shares it between cars. Dynamic load management reads the building main meter and gives the EV chargers whatever is left under the transformer limit, so far more chargers fit on the same supply. Cars still get their energy because they stay for hours.
Rules to check
Each EV circuit is a dedicated final circuit with its own RCD (Type A with 6 mA DC fault detection in the charger, or Type B) under IEC 60364-7-722, BS 7671 Section 722 and AS/NZS 3000. In Dubai, chargers connect under the DEWA EV Green Charger rules and the Dubai green building regulations ask for EV charging and EV-ready provision in new car parks. In Australia NCC 2022 J9D4 asks for EV-ready distribution capacity in new buildings. New Zealand has no mandatory share yet, so the client brief or the consent conditions set it.
Learning and checking tool. Confirm charger data, cable sizes and the current authority percentages before design sign-off.