Fleet electrification calculator: diesel vs electric

Quick scenarios

Use them as a starting point. They are built around a more realistic transition, where electrification is partial and runs alongside the existing fleet.

Tip: start with a reasonable case, then adjust battery size, route distance and electrified share.

All 4 scenarios use the same reference EV: €55,000, 89 kWh and 27 kWh/100 km. What changes is the operation, route demand and depot charging conditions, not the vehicle.

1) Volume, transition and productivity

Vehicles needed today to deliver the same service The fleet you currently need to deliver the full service. Share of service electrified now (%) It is not all or nothing. Here you choose which part of the service moves to EVs in this phase. Analysis horizon (years) Usually 4–6 years if you buy and operate the asset. Annual km per service vehicle Used for annual TCO. If unsure, stay slightly conservative. Typical daily route (km) This affects how many EVs are needed. If the route is too demanding, the model may require additional EVs. Discount rate / cost of capital (%) Used to calculate NPV. If capital is expensive for your business, increase this figure. Extra EVs due to lower productivity (%) This captures operational friction. The calculator also adds extra EVs if practical range is not enough. Driver cover for those additional vehicles (%) 0% if the current operation absorbs the extra work. 100% if each additional EV requires an additional driver. Annual labour cost per additional driver (€) Include salary, employer contributions and a realistic estimate of the full employment cost.

2) Diesel vehicle

Purchase price per diesel van (€) Fuel consumption (L/100 km) Diesel price (€/L) Annual diesel price growth (%) Annual maintenance per vehicle (€) Annual insurance per vehicle (€) Annual taxes and fees per vehicle (€) Annual downtime cost per vehicle (€) Operational cost of a vehicle being unavailable: replacement, delays, replanning or lost service. Residual value at the end of the horizon (% of purchase price)

3) Electric vehicle

Purchase price per electric van (€) EV grant / subsidy per van (€) Only deduct it if you are confident you can actually capture it. If not, stay conservative. Energy consumption (kWh/100 km) Nominal battery capacity (kWh) This affects how many EVs are required. If the route is tight, a larger battery can reduce the need for extra vehicles. Depot electricity price (€/kWh) Contingency fast charging price (€/kWh) Typical off-depot top-up charging power (kW) Used to estimate how much charging time away from the depot would be required if overnight charging is not enough. Share of energy from DC fast charging (%) Use this for contingencies. If the depot cannot cover the full energy need, the model will force at least the minimum required share at this price. Annual electricity price growth (%) Annual maintenance per EV (€) Annual insurance per EV (€) Annual taxes and fees per EV (€) Annual downtime cost per EV (€) Residual value at the end of the horizon (% of purchase price) Usable operating SOC window (%) The portion of the battery you realistically use in normal operation. It is rarely 100%. Estimated annual battery degradation (%) Route safety buffer (%) Operational reserve for weather, traffic, detours, payload variation or planning errors.

4) Depot charging and infrastructure

Installed cost per charging point (€) Unit hardware + installation. General depot electrical upgrades are handled separately. Nominal power per charging point (kW) Target useful power per point. Not every vehicle will be able to use the full nominal power.

Overnight charger setup

In conservative mode, the calculator forces 1 point per EV. In sharing mode, you can model rotation or shared parking bays.

EVs served per charging point each night Example: 1.25 means 8 points could serve roughly 10 EVs per night. Useful overnight charging window (hours) Real hours available to recover energy, not the theoretical parking time. Overall charging efficiency (%) Includes charger, cabling and battery losses. 88–92% is usually a reasonable range. Building / depot base load (kW) Existing depot consumption: lighting, refrigeration, offices, workshop, etc. Contracted or available depot power (kW) The total electrical capacity currently available at the depot. Real utilisation with dynamic load management (%) How much of the available power you can actually use through smart charging and intelligent load distribution. Electrical upgrade / works / commissioning (€) Grid connection, switchboards, protection systems, civil works, engineering or depot adaptations.

5) Cross-cutting assumptions

Annual maintenance cost growth (%) Annual growth of other costs (%)

This calculator is built for an initial operational decision. It includes the factors that usually move the case the most — vehicles, drivers, battery, energy, infrastructure, degradation and real depot power — but it does not yet include advanced tax effects, leasing, financing or second-life battery value. If any of those are material in your case, the model should be refined before making a final decision.

Executive summary

Mixed EV + diesel transition versus staying fully diesel.

Calculating

TCO saving from transition vs diesel

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Estimated payback

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Initial transition CAPEX

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All-diesel fleet vs mixed fleet

Cost per km

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Diesel vs transition

Quick read

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Best NPV mix

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Operational EV fit

Service electrified now

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Equivalent service vehicles

Actual EVs required

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Higher of productivity and range requirement

Equivalent extra drivers

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Annual labour impact

Recommended charging points

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Minimum average overnight power

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To replenish daily energy

Useful available power

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After base load and smart charging

Practical range at horizon end

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Impact of degradation and assigned average route

Route risk

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Depot feasibility

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Off-depot top-up charging

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Sensitivity

Which variables move the result the most.

Annual model detail

Year-by-year table showing energy price evolution, OPEX and cumulative cost. Residual value is discounted at the end.

Equivalent service analysed: —

Year	Diesel price	EV energy price	Diesel OPEX	Transition OPEX	Transition upside	Cumulative diesel cost	Cumulative transition cost

What usually breaks the EV case

Heavy dependence on expensive, unplanned fast charging.
Insufficient depot power or poor utilisation of available power.
More EVs or more drivers needed to deliver the same service.
Battery size or practical range too tight for the target route.

What usually helps the EV case

Progressive electrification, not a big-bang switch.
Cheap, disciplined overnight charging at the depot.
Good dynamic power management and load distribution.
Enough battery to cover the route with real operational margin.

Where Autonality comes in

This calculator helps you decide whether it is worth moving forward. Autonality then helps you run the operation in the real world: vehicle-route assignment, charging certainty, incidents, maintenance and a combined view of vehicles + chargers.

Talk to Autonality See last-mile use case

Does electrifying your fleet make sense? Run the numbers with operational discipline