For most apartment residents who park overnight, a 3.3 kW charging point is enough. At 3.3 kW you add roughly 3 kWh to the battery per hour of charging — a typical daily car commute of 40 km (at ~6 km/kWh) needs about 7 kWh, or a bit over two hours of charging. Overnight parking gives you eight or more. A 7.2 kW wall box halves charging times, which matters if you drive long daily distances, share the charger, or often need a fast top-up — but it draws more current, frequently requires a sanctioned-load enhancement, and costs more to wire.
The maths that actually matters
| Question | 3.3 kW | 7.2 kW |
|---|---|---|
| Energy added per hour (approx.) | ~3 kWh | ~6.5–7 kWh |
| Time to add 20 kWh (typical 20→80% on a mid-size car) | ~6–7 hours | ~3 hours |
| Typical two-wheeler full charge (3 kWh) | ~1 hour of energy — but see note | Rarely supported by the vehicle |
Note: the vehicle's onboard charger limits AC charging speed. Many two-wheelers and some cars cannot draw more than 3.3 kW regardless of the wall unit — check your vehicle's AC charging specification before paying for 7.2 kW. [PLACEHOLDER: do not publish model-specific charging rates without the manufacturer's specification as source.]
Run your own numbers in the charger cost calculator — it computes charging time at both power levels.
Electrical requirements
- 3.3 kW draws about 15 A on a single phase — the same order as a geyser or large AC. It may fit within a typical domestic sanctioned load, but that is a per-flat fact your electrician must verify against your bill and panel.
- 7.2 kW draws about 32 A single-phase. Many flats need a load enhancement from the DISCOM, heavier cable and higher-rated protection. [PLACEHOLDER: verify the load-enhancement procedure and cost for your DISCOM with source and date.]
Both need a dedicated circuit with MCB and RCCB/RCBO protection and verified earthing — non-negotiable in both cases, and always professionally installed.
Installation cost difference
The 7.2 kW route costs more three times over: the wall box costs more than a heavy-duty socket point, the cable must be thicker for the same run, and the load-enhancement process adds fees and time. Our calculator's installation ranges use editorially maintained sample assumptions you can inspect — as a pattern, expect the 7.2 kW installed cost to be roughly double to triple a basic 3.3 kW point for the same cable distance. Real quotes vary widely; treat every figure as an estimate.
How to choose
- Choose 3.3 kW if: you park overnight at your own spot, drive typical city distances, or own a two-wheeler. It is cheaper, easier to approve, and usually sufficient.
- Choose 7.2 kW if: your vehicle supports it AND you regularly need faster turnarounds — high daily mileage, shared use across residents, or unpredictable schedules.
- Either way: confirm the vehicle's AC limit first, then let a licensed electrician confirm what your connection supports before buying anything.
For shared installations where several residents will use one point, see private versus shared charging — throughput, not peak speed, is usually the real constraint.