Continue from your trip-cost estimate
Verify the consumption input, turn the calculation into a resilient route plan or use a quick economy conversion before comparing alternatives.
What drives the cost of this journey?
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One route calculator, four external energy paths
A conventional car and a non-plug-in hybrid buy liquid fuel. A plug-in hybrid can buy both fuel and electricity. A battery EV buys electricity, while a hydrogen fuel-cell vehicle buys compressed hydrogen and converts it into electricity on board. The calculator keeps those quantities separate instead of forcing every vehicle into a fake petrol equivalent.
The common comparison point is money per journey and money per 100 km. That makes route budgeting possible without claiming that litres, kWh and kilograms are physically interchangeable. Additional tolls and parking are added after propulsion cost, so you can see whether the vehicle energy or the route fees dominate the result.
This is a journey model, not a full cost-of-ownership calculation. Depreciation, insurance, tax, tyres, servicing and financing are deliberately left for the later Automotive ownership calculator.
Choose the mode that matches the vehicle
| Vehicle | Calculator mode | Main inputs | Important boundary |
|---|---|---|---|
| Petrol, diesel or LPG car | Liquid fuel | L/100 km or MPG and price per litre/gallon | Use the fuel and price units actually quoted. |
| Full or mild hybrid (HEV) | Liquid fuel | Measured hybrid fuel economy and fuel price | Regenerative energy is internal; no plug electricity is purchased. |
| Plug-in hybrid (PHEV) | PHEV | Electric-distance share, engine-mode L/100 km, kWh/100 km and both prices | Use consumption values for each operating share, not a blended brochure number. |
| Battery EV | Electric | kWh/100 km, charging losses and electricity price | Check whether the consumption already includes charging losses. |
| Hydrogen FCEV | Hydrogen | kg/100 km, price per kg and optional tank kilograms | Confirm that a usable hydrogen station is available on the route. |
Distance, return travel and shared costs
Enter road distance for one direction. When return travel is selected, the calculator multiplies that distance by two before calculating energy. This works when the return route is roughly the same length and consumption. If the return takes a different route, includes a trailer or has a very different elevation profile, calculate the two legs separately.
Tolls, ferries, parking and other known costs are entered as one total for the complete journey. They are not doubled, because a parking fee may apply once and toll structures may differ by direction. Cost per person divides propulsion energy plus these additional costs by the number of people.
Cost sharing is arithmetic only. It does not decide which costs should legally or socially be shared.
Liquid fuel and HEV formulas
After converting MPG when necessary, fuel required is calculated from L/100 km:
US MPG converts with 235.214583 ÷ MPG, while UK MPG converts with 282.480936 ÷ MPG. The fuel-price selector also matters because a US gallon and an imperial gallon contain different volumes.
For a non-plug-in hybrid, use its actual fuel economy in this same mode. The traction motor and battery change how efficiently the vehicle uses the fuel, but the externally purchased route energy remains liquid fuel.
PHEV: separate electric and engine-powered kilometres
A plug-in hybrid cannot be represented accurately by one fuel number when part of the route runs from externally charged electricity. The calculator first divides total distance using the entered electric share. Battery energy applies only to electric kilometres; engine-mode fuel consumption applies only to the remaining kilometres.
Battery-side kWh are divided by charging efficiency to estimate grid kWh. Fuel and electricity costs are then added. A 60% electric share is a route assumption, not a permanent characteristic of the car: charging opportunity, temperature, speed, cabin heating and control strategy can change it.
Avoid entering a very low weighted certification fuel figure as engine-mode consumption. The field asks what the vehicle uses while the combustion engine is serving the non-electric share.
EV: battery energy versus metered energy
Vehicle consumption in kWh/100 km often refers to energy delivered from the traction battery. The driver pays for energy measured at the charger or meter. With a loss assumption L, the calculator uses:
At 10% losses, 90 kWh on the battery side requires 100 kWh from the grid. If your kWh/100 km figure was already measured at a wallbox or public charger, set the separate loss input to 0% to avoid counting the same losses twice.
This route page uses one electricity price. For a monthly home/public charging split, subscription tariffs and detailed loss reporting, use the dedicated EV Charging Cost Calculator.
Hydrogen FCEV: price kilograms, not electricity
A fuel-cell electric vehicle drives through an electric motor, but it buys hydrogen at the station. The on-board fuel cell converts hydrogen energy into electricity. Route hydrogen demand is therefore:
When tank capacity is entered, estimated range equals tank kilograms divided by kg/100 km and multiplied by 100. Actual usable range varies with conditions and reserve strategy. More importantly, station availability can be the binding route constraint even when the mathematical range is sufficient.
The calculator does not label hydrogen automatically as low-carbon. Tailpipe operation and upstream hydrogen production are different boundaries and require separate data.
Where to get credible inputs
| Input | Practical source | Check before using it |
|---|---|---|
| Road distance | Navigation route or recent trip log | Use road distance, not straight-line distance. |
| Fuel economy | Fill-to-fill records or long-term display | Match route conditions and select US/UK MPG correctly. |
| PHEV electric share | Vehicle app or a realistic route scenario | Base it on charging access and actual electric range. |
| EV/PHEV electricity use | Long-term vehicle value or trip history | Identify whether the figure is battery-side or grid-side. |
| Hydrogen consumption | Vehicle data or measured refuelling history | Use kg/100 km for the selected vehicle and conditions. |
| Energy price | Available station, charger or tariff | Use the correct unit and include separate fees under other costs. |
| Tolls and parking | Route operator, booking or parking tariff | Enter the full-trip total only once. |
Consumption sensitivity for the same route
The table keeps distance, energy prices, additional costs and passenger count unchanged. It changes active consumption inputs by −10% and +10% to show how sensitive the journey is to real-world efficiency.
| Scenario | Propulsion energy cost | Total trip cost | Cost / 100 km | Cost / person |
|---|---|---|---|---|
| — | ||||
In PHEV mode, both engine-mode fuel consumption and electric consumption move together while the electric-distance share stays unchanged.
Worked examples
Example 1 – fuel return trip
A car travels 180 km each way, uses 6.5 L/100 km and fuel costs €1.75/L. Tolls for the complete trip are €24. Two people share the cost.
- Total distance = 180 × 2 = 360 km.
- Fuel = 360 × 6.5 ÷ 100 = 23.4 L.
- Fuel cost = 23.4 × €1.75 = €40.95.
- Total = €40.95 + €24 = €64.95.
- Per person = €64.95 ÷ 2 = €32.48.
Example 2 – battery EV
An EV covers a 250 km one-way route at 18 kWh/100 km. Charging losses are 10% and electricity costs €0.45/kWh.
- Battery energy = 250 × 18 ÷ 100 = 45 kWh.
- Charging efficiency = 90%.
- Grid energy = 45 ÷ 0.90 = 50 kWh.
- Energy cost = 50 × €0.45 = €22.50.
Practice for students and apprentices
A PHEV makes a 300 km return journey. Sixty percent of the distance is electric. It uses 18 kWh/100 km on the electric share and 6.8 L/100 km on the engine share. Charging losses are 10%, electricity costs €0.32/kWh and fuel costs €1.80/L. Calculate grid energy, fuel, propulsion cost and cost per 100 km before tolls.
- Electric distance = 300 × 60% = 180 km; fuel distance = 120 km.
- Battery energy = 180 × 18 ÷ 100 = 32.4 kWh.
- Grid energy = 32.4 ÷ 0.90 = 36 kWh; electricity cost = 36 × €0.32 = €11.52.
- Fuel = 120 × 6.8 ÷ 100 = 8.16 L; fuel cost = 8.16 × €1.80 = €14.69.
- Total propulsion cost = €26.21; cost per 100 km = €8.74.
Common mistakes
- Entering total return distance while also selecting return travel.
- Mixing US MPG with UK gallons or UK MPG with US fuel-price units.
- Using a PHEV weighted brochure fuel figure as engine-only consumption.
- Applying charging losses again to a grid-metered kWh/100 km value.
- Multiplying tolls automatically even though the field already expects a complete-trip total.
- Comparing costs per journey when route lengths differ instead of checking cost per 100 km.
- Using a hydrogen price from a market where the vehicle cannot actually refuel.
- Treating an example price as a current local quote.
Limits and the correct next decision
Weather, speed, congestion, gradients, payload, tyre pressure, cabin heating, towing and detours can change consumption. The calculator uses one average for each active energy path. It does not model charging curves, battery state of charge, fuel reserve, station queues or route-specific refuelling stops.
It also does not compare full environmental impact. A zero-tailpipe-pollution claim is not a lifecycle result: electricity mix, fuel pathway and hydrogen production must be evaluated using a declared boundary and current regional data.
Use this result to budget one journey. The next Automotive calculator will expand the view to annual and ownership costs, including depreciation, insurance, service, tyres, taxes and cost per kilometre for different powertrains.