There is no chargers-per-employee ratio worth using, and total headcount is the wrong starting number anyway. What decides the count is how many EV drivers actually park at your site on a typical day. A short internal census gives you that figure, plus the arrival pattern that decides how far each charger stretches.
Key Takeaways
- No chargers-per-employee ratio exists as a standard — headcount is the wrong denominator.
- A four-question census gives you the driver pool, attendance and likely daily plug-ins.
- Arrival spread and workday dwell decide how far each bay stretches.
- Build capacity for near-term joiners, install ports for today’s drivers, then measure.
Why Headcount Misleads
A per-employee ratio treats every employee as a daily EV driver. At a real site, four filters cut that number down before a single charger is counted:
- Not everyone drives. Some staff commute by train, bike, bus or car-share, and never need a bay.
- Not everyone is on site daily. Hybrid schedules mean attendance, not employment, puts cars in the car park.
- Not every EV driver needs a charge at work. Drivers with home charging may top up at work only occasionally, or not at all.
- Some demand is not staff at all. Pool cars, visitors and contractors can add load that a staff ratio misses completely.
A ratio applied to the wrong denominator either strands capital in idle chargers or opens with a waiting list. Our workplace EV charging program guide covers the wider planning; this article is the count itself.
The Census: Four Questions to Ask Staff
A one-page survey, run before any hardware decision, replaces the guesswork. Four questions do most of the work:
- Do you drive an electric or plug-in hybrid car to this site?
- How many days in a typical week are you on site?
- If chargers were installed, how often would you expect to plug in — most days, some days, rarely?
- Are you planning to buy an EV in the next year or two?
The fourth answer is your near-term joiners line: an internal estimate, not a promise, but it is the figure that tells you how much electrical capacity and bay layout to build in now, even if the ports themselves wait.
From Census to a Daily Driver Count
The example below is an illustration with invented inputs — run it with your own survey results. It shows the shape of the arithmetic, not a standard.
| Step | Illustration (invented inputs) | What it gives you |
|---|---|---|
| Employees at the site | 200 | The headcount — the number a ratio would use |
| Survey answers returned | 178 | A response rate worth trusting |
| Staff who drive an EV or plug-in hybrid | 41 | Your driver pool, from their own answers |
| Of those, on site on a typical day | About 34 | Attendance applied — the daily demand ceiling |
| Of those, expecting to plug in that day | About 24 | The number charger planning actually starts from |
Two checks finish the picture. Arrival spread: if most drivers arrive inside the same hour and leave together, each bay turns over only at midday at best; staggered shifts and part-time patterns stretch the same bays further. Dwell: U.S. DOT figures put Level 2 charging at 10–20 miles of range per hour, and a car parked for a full workday needs only a top-up for the commute — so one bay can serve a morning and an afternoon car where drivers swap. Your daily driver count, read against dwell and arrival spread, is what the port count is then built from — and the session data from the first term replaces the survey with measurements.
Hardware That Counts With You
However the count lands, choose hardware that keeps counting after opening day. The EV-AC03201T dual-connector AC station serves two bays from one unit — two Type 2 connectors sharing up to 43 kW, with OCPP 1.6J and RFID — so every session is recorded per driver, which is exactly the data the next census round needs. EVDANCE’s commercial EV charging solutions cover larger staff car parks built the same way.
Frequently Asked Questions
Is there an official chargers-per-employee ratio we should follow?
No regulator or standard publishes one. Ratios quoted by vendors are rules of thumb built on someone else’s site; your census, attendance and dwell times are the inputs that make the count right for yours.
Should we count staff who plan to buy an EV soon?
Count them, but as a separate line. Size conduit, panel capacity and bay layout with the joiners in mind, and install ports for the drivers you have now — adding ports to prepared bays later is the cheap step.
How often should we repeat the census?
Once before launch, then let session data take over. Repeat the survey when the picture visibly changes — a hiring round, an office move, or chargers that sit full every day by nine in the morning.
Related Reading
- How to Plan a Workplace EV Charging Program
- How Much Do Commercial EV Chargers Cost?
- How Do Commercial EV Charging Stations Work?
- RFID and User Management for Shared EV Chargers
