The formula for EV cost per 100 km is simple: multiply your car's energy consumption (kWh/100 km) by your electricity price (€/kWh). A Tesla Model 3 consuming 14.9 kWh/100 km charged at a home rate of €0.20/kWh costs €2.98 per 100 km. A Volkswagen ID.4 at 17.5 kWh/100 km costs €3.50 per 100 km at the same rate.
EV vs Petrol: Real Cost Per 100 km Compared
Real-world consumption is typically 10-20% higher than WLTP ratings, depending on driving style, temperature, and speed. Highway driving at 130 km/h can increase consumption by 30-50% compared to city driving. In winter, expect 20-30% higher consumption due to battery heating and cabin climate control.
Don't forget charging efficiency losses. When you charge at home via AC, about 8% of the energy is lost before reaching the battery. So your effective cost is closer to €3.24/100 km for that Model 3, and €3.80/100 km for the ID.4. The Plan EV Charge calculator factors in these losses automatically.
Petrol Cost Per 100 km: The Comparison Baseline
Petrol cost per 100 km equals fuel consumption (L/100 km) multiplied by fuel price (€/L). A VW Golf 1.5 TSI consuming 6.5 L/100 km at €1.70/L costs €11.05 per 100 km. A BMW 3 Series at 7.2 L/100 km costs €12.24 per 100 km. These are WLTP figures; real-world consumption is often 15-25% higher.
Diesel vehicles are somewhat cheaper to run per kilometer due to better fuel efficiency, but diesel fuel prices are often similar to or higher than petrol in many European countries. A VW Golf TDI at 5.0 L/100 km and €1.75/L diesel costs €8.75/100 km, still nearly three times the EV equivalent.
Fuel prices are also far more volatile than electricity. Petrol prices in Europe have swung between €1.30 and €2.20/L in recent years, making monthly budgeting unpredictable. Electricity rates, especially fixed-rate home contracts, provide much more cost stability.
Head-to-Head: Real Examples Compared
Let's compare equivalent vehicles directly. The Volkswagen ID.4 Pro (EV) versus the VW Tiguan 1.5 TSI (petrol): the ID.4 costs approximately €3.80/100 km at home charging rates (€0.20/kWh), while the Tiguan costs €12.75/100 km (7.5 L/100 km at €1.70/L). That's a 70% saving on fuel alone. Over 15,000 km/year, you save roughly €1,343 annually.
The Tesla Model 3 versus the BMW 3 Series 320i is another revealing comparison. The Model 3 at €3.24/100 km versus the BMW at €12.24/100 km saves €1,350/year over 15,000 km. Even if you charge the Model 3 exclusively on public fast chargers at €0.50/kWh, the cost rises to about €8.10/100 km, still cheaper than the petrol BMW.
For the Hyundai Ioniq 5 versus the Hyundai Tucson, the pattern holds: approximately €3.90/100 km versus €11.56/100 km. The EV advantage is consistent across segments, from city cars to SUVs, typically saving 60-75% on fuel costs when charging at home.
Total Cost of Ownership: Beyond Fuel
Fuel savings are just one piece of the puzzle. EVs also have dramatically lower maintenance costs. No oil changes, no timing belts, no exhaust system repairs, and regenerative braking means brake pads last 2-3 times longer. Annual maintenance for an EV typically runs €200-€400 versus €600-€1,200 for a comparable petrol car.
Insurance can be higher for EVs due to higher purchase prices and repair costs, though the gap is narrowing. Tax incentives vary by country but often favor EVs: many European countries offer reduced or zero road tax, registration tax benefits, and sometimes purchase subsidies. In Norway, EVs are exempt from VAT. In France, the ecological bonus can reduce the purchase price by several thousand euros.
Depreciation is the wildcard. Early EVs depreciated faster due to battery concerns, but modern EVs with better batteries are holding value well. The total cost of ownership over 5 years and 75,000 km typically favors EVs by €5,000-€15,000 compared to equivalent petrol models, depending on local incentives and electricity rates.
Using Plan EV Charge to Compare with Petrol
The Plan EV Charge calculator includes an ICE comparison feature that makes these calculations effortless. After simulating a charge for your EV, the tool shows you what the equivalent journey would cost in a petrol vehicle. You can customize the petrol car's consumption (L/100 km) and your local fuel price to get an accurate side-by-side comparison.
This is particularly useful when you're considering switching from a specific petrol car to an EV. Enter your current car's real fuel consumption, your typical driving patterns, and see exactly how much you'd save each month. The calculator accounts for charging efficiency losses that simple online comparisons often ignore.
For road trip planning, the comparison becomes even more valuable. While daily commuting almost always favors home charging, long trips with multiple DC fast charging stops narrow the gap. The calculator lets you model these mixed scenarios realistically, so you know whether a particular trip is cheaper by EV or whether the petrol car still wins on pure cost for that specific journey.
