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A420iPetrolvsB118dDiesel
  • MotorwayMotorwayRange and charging
  • PerformancePerformance0-100, top speed
  • ConsumptionConsumptionYearly cost
  • Specs420i · 118d

BMW 420i Steptronic Gran Coupe G22 vs BMW 118d F20LCI

Trip mapped at a glance. Charging stops visible, total duration predictable. Caralogy simulation at 130 km/h.

saloon · 2021 vs 2018 · Paris → Marseille · 775 km · 130 km/h
BMWPetrol

420i Steptronic Gran Coupe G22

184 ch · 2021

VS
BMWDiesel

118d F20LCI

150 ch · 2018

Simulation trip
Assumptions: 130 km/h · start réservoir plein · mild weather

Result · total trip time

ABMW 420i Steptronic Gran Coupe G22

7h01no stop

0 stops · 89.13 €

GapLess than a minute apart
BBMW 118d F20LCI

7h01no stop

0 stops · 68.95 €

Paris → Marseille · 130 km/h · Caralogy simulation
Measure420i Steptronic Gran Coupe G22118d F20LCIGap
Total time7h017h01Less than a minute apart
Charging stops0 stops0 stopsSame
Cost of energy used89.13 €68.95 €20.18 € · 118d F20LCI

Visualise the trip

Both vehicles drive at 130 km/h. The difference comes from charging stops.

BMWPetrol
420i Steptronic Gran Coupe G22
100%
1132 km
Range
Paris
0 km · departure
Marseille
775 km · Arrival 7h01
0
Stops
7h01
Duration
89.13 €
Cost of energy used
BMWDiesel
118d F20LCI
100%
1268 km
Range
Paris
0 km · departure
Marseille
775 km · Arrival 7h01
0
Stops
7h01
Duration
68.95 €
Cost of energy used

Very close result: less than one minute apart on this route. Both vehicles are evenly matched on the motorway over this distance.

Both vehicles drove at 130 km/h for the entire trip. The gap is built at the stops: no stop for the 420i Steptronic Gran Coupe G22 versus no stop for the 118d F20LCI.

Motorway consumption: the Caralogy methodology

The official WLTP figures (6,3 L/100km for 420i Steptronic Gran Coupe G22 and 4,6 L/100km for 118d F20LCI) are measured on a mixed cycle averaging ~46 km/h. At a steady 130 km/h, aerodynamic drag weighs much more heavily - it grows with the square of speed. Caralogy calculates a motorway consumption specific to each vehicle based on its aerodynamic profile (SCx), weight and power curve - not a uniform correction factor. For this trip, the simulation yields 5,3 L/100km (420i Steptronic Gran Coupe G22) and 4,1 L/100km (118d F20LCI). Full methodology: see the assumptions below the controls.

Energy cost breakdown for your trip Paris → Marseille

The cost per kilometre depends on the electricity rate applied to each segment - based on the energy source used at that point of the trip.

BMW 420i Steptronic Gran Coupe G22

SegmentEnergy usedDistanceConsumption€/kmCost (€)
Paris → Marseillefuel · 2.17 €/L775 km41 L consumed0.115 €/km89.13 €
Trip total89.13 €

BMW 118d F20LCI

SegmentEnergy usedDistanceConsumption€/kmCost (€)
Paris → Marseillefuel · 2.17 €/L775 km32 L consumed0.089 €/km68.95 €
Trip total68.95 €

What produces these figures

WLTP combined consumption
6.3 L/100 km · 4.6 L/100 km
Fuel tank
60 L · 52 L

Compare with another vehicle

Replace one of the two with an alternative from the same segment

BMWPetrol

420i Steptronic Gran Coupe G22

184 ch · 2021

BMWDiesel

118d F20LCI

150 ch · 2018

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Frequently asked questions

On Paris → Marseille (775 km at 130 km/h), the 420i Steptronic Gran Coupe G22 arrives in 7h01 with 0 fuel stops.

WLTP consumption does not reflect motorway reality. Aerodynamic drag grows with the square of speed, so real consumption is 15 to 25 % higher than WLTP combined. Caralogy calculates a highway consumption specific to each vehicle based on its aerodynamic profile (SCx), weight and power curve.

Total time = driving time + charging time. Driving time is calculated at an average speed of 130 km/h on the motorway (adjustable). Charging time is calculated based on the real power curve of each vehicle, respecting the optimal 10 → 80 % range and the maximum power accepted by the chargers on the route.

No. The displayed cost covers only the energy consumed during the trip: kWh × energy rate, with a mix of home charging and DC fast chargers. Battery wear is a long-term ownership cost, not a trip cost.

On this trip, the energy used costs 89.13 € (420i Steptronic Gran Coupe G22) and 68.95 € (118d F20LCI). For reference, an equivalent Peugeot 508 1.6 PureTech 180 (~7.2 L/100 km) would cost about 103 € in fuel.