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Home›Consumption›BMW 840i vs Porsche Panamera 4

Consumption comparison

BMW 840i xDrive Convertible G15 vs Porsche Panamera 4 Sport Turismo 971: how much do I save per year?

Same car, two powertrains. The simulator below calculates the gap based on your mileage and charging type.

BMWPetrolMost economical

840i xDrive Convertible G15

68 L · 2021

8,0 L/100km

VS
PorschePetrol

Panamera 4 Sport Turismo 971

23.7 L · 2018

10,2 L/100km

MotorwayRange & chargingPerformance0-100, top speedConsumptionAnnual TCO

Annual mileage

15 000 km/an

5 000 km50 000 km

Simulated driving mix

Drag anywhere on the bar to adjust

Fuel price

Petrol 95 : 1,99 €/L·Diesel : 1,75 €/L

Annual energy cost · 15 000 km

Typical annual usage : Mix 30% city / 50% road / 20% motorway

BMWPetrolMost economical

840i xDrive Convertible G15

Annual energy cost · 15 000 km

2 507€

16,72 € / 100 km

Equivalent to 1 260 L of petrol 95 per year

Weighted consumption
8,4 L/100km
Fuel price
1,99 €/L
Fuel used
1260,0 L per year
PorschePetrol

Panamera 4 Sport Turismo 971

Annual energy cost · 15 000 km

3 045€

20,30 € / 100 km

Equivalent to 1 530 L of petrol 95 per year

Weighted consumption
10,2 L/100km
Fuel price
1,99 €/L
Fuel used
1530,0 L per year
Annual gap 840i xDrive Convertible vs Panamera 4 Sport Turismo+537 €/an≈ 270 L petrol 95

BMW 840i xDrive Convertible G15 costs 537 €/an less in energy than Porsche Panamera 4 Sport Turismo 971, over 15 000 km for this driving mix.

≈ 270 L of petrol 95 saved per year

Your savings over the ownership period

Cumulative projection by annual mileage. The cheaper-to-run vehicle widens the gap year after year.

Annual mileage

15 000 km/an

1 year

537 €

≈ 270 L petrol 95

3 years

1 612 €

≈ 810 L petrol 95

5 years

2 686 €

≈ 1350 L petrol 95

10 years

5 373 €

≈ 2700 L petrol 95

Cumulative savings for BMW 840i xDrive Convertible G15 versus Porsche Panamera 4 Sport Turismo 971. Excluding purchase, insurance, maintenance and depreciation.

Annual fuel cost breakdown

Projection over 15 000 km/year.

BMW

840i xDrive Convertible G15

Fuelkm/year€/kmAnnual cost
Annual fuel1,99 €/L15 000 km0,167 €/km2 507 €
Porsche

Panamera 4 Sport Turismo 971

Fuelkm/year€/kmAnnual cost
Annual fuel1,99 €/L15 000 km0,203 €/km3 045 €

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Frequently asked questions

On a 100 km mixed trip, the BMW 840i xDrive Convertible is about 20% cheaper than the Porsche Panamera 4 Sport Turismo with default parameters. This ratio shifts with your actual energy prices — simulate for your profile.

The BMW 840i xDrive Convertible is cheaper across all distances with default rates. If your energy prices differ significantly, simulate to see the real impact on your budget.