Commercial Road Transport: Heavy-Duty EV Operation and Charging
What this domain tests
The Commercial road transport domain tests heavy electric truck and bus operation: gross vehicle mass (GVM), payload, route energy planning, DC charging, regenerative braking, thermal management and pre-trip inspection. Questions expect you to calculate rather than quote brochure figures.
Core rules and concepts
- Payload = GVM minus kerb mass, where kerb mass includes body, battery, fluids and specified equipment. A larger battery directly reduces freight capacity.
- Range planning uses measured kWh/km at the actual payload, gradient, speed and climate. HVAC, headwinds and low temperature raise consumption.
- DC charging is limited by charger, vehicle and SoC curve. Power tapers as the pack fills; plan opportunity charging before the taper zone.
- Regenerative braking recovers energy but is limited by high SoC, cold cells and charge acceptance. Service brakes remain the primary brake; monitor battery SoC and brake temperature on long descents.
- Pre-trip inspection includes charge port condition, cable and plug temperature, coolant level, HV warning labels and tyre load rating.
Worked example
A rigid truck has GVM 26,000 kg and kerb mass 13,200 kg, so payload is 12,800 kg. A 180 km route uses 1.3 kWh/km at this weight: 180 × 1.3 = 234 kWh. The usable pack is 270 kWh, but a 15% reserve leaves 229.5 kWh. The route needs 234 kWh, so it is short by 4.5 kWh under these assumptions. You either add a top-up charge, reduce payload or confirm a lower measured consumption before dispatch. If consumption is 1.2 kWh/km, energy is 216 kWh and the route is feasible with the reserve.
Traps that cost marks
Using unladen or brochure range; forgetting that body and battery reduce payload; assuming a 350 kW charger delivers 350 kW to the truck; charging to 100% daily on an NMC pack; ignoring regen fade at high SoC; and not checking cable/plug temperature after a high-power session.