Golf eTSI, 5.0 l/100 km, 15,000 km
Energy cost (first year)
€113/month
- Per year
- €1,350
- Cost per kilometre
- €0.090/km
- Total over the period, inflation included
- €7,167
Free calculator · Energy, financing, resale · 2026
Fuel and electricity cost calculator
Energy is often the second-largest item after depreciation. Real consumption, kilometres per year, price per litre or per kWh and share of home charging: the calculator projects the cost over your holding period, inflation included.
Your parameters
Examples:
l or kWh / 100 km
Electric: kWh/100 km. Combustion: l/100 km. PHEV: the weighted WLTP figure is replaced by a realistic estimate below 3.6 l.
km
€/l
years
%
Result
Energy cost (first year)
€135/month
- Per year
- €1,620
- Cost per kilometre
- €0.108/km
- Total over the period, inflation included
- €8,601
Same mileage, other powertrains (reference consumption, first year)
| Powertrain | Consumption retained | Annual cost |
|---|---|---|
| Petrol | 6.5 | €1,755 |
| Diesel | 5.5 | €1,444 |
| Plug-in hybrid | 1.8 | €1,456 |
| Electric | 17 | €1,211 |
Calculate the full true cost
The full calculation sets energy against loss of value and the tax saving: that is where electric and combustion part ways.
Worked examples 2026
Calculated by the same engine as the full true cost calculation, never estimated by an AI.
Tesla Model 3, 13 kWh/100 km, 20,000 km, 80% at home
Energy cost (first year)
€80/month
- Per year
- €962
- Cost per kilometre
- €0.048/km
- Weighted electricity price home / public
- 0.37
Golf eHybrid (PHEV), 25,000 km
Energy cost (first year)
€202/month
- Per year
- €2,428
- Cost per kilometre
- €0.097/km
- Weighted electricity price home / public
- 0.48
How it is calculated
Combustion: cost/km = consumption / 100 × price per litre · electric: consumption / 100 × weighted price per kWh Weighted price per kWh = home price × home share + public price × (1 − home share) PHEV: 40% of km electric (17 kWh/100 km) + 60% combustion (6 l/100 km if the WLTP figure is unrealistic) Year n = year 1 cost × (1 + inflation)^(n − 1)
The energy cost is the product of consumption, mileage and unit price. For an electric car, the price per kWh depends heavily on where you charge: the calculator weights the home tariff and the public charger tariff according to the share you indicate.
The WLTP consumption figures of plug-in hybrids (often 1 to 2 l/100 km) assume an always-full battery. The engine uses a more realistic mix: 40% of kilometres electric at 17 kWh/100 km and 60% combustion at 6 l/100 km, unless the declared consumption exceeds 3.6 l.
The result is the “Energy” category of the TCO. The table compares the same usage with reference consumption figures by powertrain, to position your vehicle.
Frequently asked questions
How much does electricity cost for 15,000 km per year?
With 17 kWh/100 km and a weighted price of €0.475/kWh (half at home at €0.30, half at chargers at €0.65), 15,000 km cost about €1,211 per year, i.e. €101 per month. At 100% home charging, the cost drops to €765 per year.
Why is my plug-in hybrid’s WLTP consumption not used?
Because it assumes an always-charged battery and short journeys. Real fleet readings show consumption 2 to 4 times higher. The calculator uses a 40% electric / 60% petrol mix, closer to average use.
Which fuel price should I use?
By default €1.80/l for petrol and €1.75/l for diesel, close to recent Belgian maximum prices. Adjust them to your actual prices and expected inflation: the engine applies an annual increase of 3% by default.
Is energy deductible?
For a company or a self-employed person, yes, at the vehicle’s CO2 deductibility rate. The fuel of a plug-in hybrid ordered since 2023 is capped at 50%, electricity follows the vehicle’s rate. The TCO applies these rules in its tax saving.