How to Charge Residents for EV Charging in a Condo or Car Park
A practical guide for management offices: how to meter each EV charging bay, bill residents per kWh with prepaid balances, and add leakage protection.
As more residents buy electric cars, management offices face a new question: who pays for the electricity? When residents plug into the car park supply, the charging cost lands on everyone's maintenance fees. This guide explains how to meter each bay and bill residents fairly.
The problem with shared charging
- Common power pays for private cars. Residents without EVs subsidise those with them.
- No way to prove usage. Without a meter per bay, there's no fair basis for a charge.
- Smart chargers are expensive. Networked OCPP chargers and their billing back-ends cost far more than the basic AC chargers many residents already own.
The approach: meter the bay, not the charger
Instead of replacing chargers, put a smart meter or smart breaker on each charging bay's circuit. The meter measures every kWh that flows to that bay, whatever charger is connected, and the platform bills it to that resident.
This works with basic AC wallboxes and doesn't require OCPP.
Step by step
- Meter each bay. Install a wall-mounted meter beside each charger, a DIN-rail meter in the distribution board, or one channel of a PSNA-6 modular breaker per bay.
- Give each resident a balance. Each bay is linked to a prepaid balance.
- Residents top up. Online through the payment gateway, or the management office tops up balances directly.
- Charging is deducted per kWh at the rate you set.
- Cut-off at zero. The bay switches off automatically when the balance runs out, and is switched back on remotely after top-up.
Which hardware?
| Situation | Recommended |
|---|---|
| Meter beside each charger | SplinergySW W1P-4G wall-mounted meter |
| Single-phase chargers, meters in the DB | SplinergySW D1P-4G |
| Three-phase (22 kW) chargers | SplinergySW D3P-4G |
| Leakage protection on every bay | PSNA-6 modular smart breaker |
Car parks rarely have good Wi-Fi, so 4G models are usually the right choice.
Why leakage protection matters
EV charging draws high current for hours at a time, often outdoors or in damp basements. The PSNA-6 modular breaker adds residual-current (leakage) protection on every bay, configurable between 10 and 30 mA, plus over- and under-voltage trip. It protects the building's main switchboard from a fault on a single bay.
What it costs
- Meters from RM 200 for single-phase 4G.
- Platform RM 10 per meter per month, 12-month contract paid upfront.
- 4G data plans from RM 35 per SIM per year.
For a 10-bay car park with 4G wall-mounted meters, use the estimator on the EV charging page, or send us your bay count for a proposal.
Adding EV charging to a building?
Tell us how many bays and what chargers you have, and we'll recommend the setup.