Fleet ROI modeling is the structured financial and operational model used to evaluate whether electrifying a fleet (vehicles + charging + energy + service) delivers positive returns versus staying with ICE. A good model connects CAPEX and OPEX to real fleet outcomes: €/km, vehicle readiness, peak demand, and scalability—not just “charger cost vs fuel savings”.
What a fleet ROI model should cover
1) Vehicle economics (TCO layer)
– Purchase/lease cost and term
– Residual value assumptions (or lease return conditions)
– Energy consumption (kWh/km) vs fuel consumption (L/100 km)
– Maintenance, tires, downtime-related costs
– Insurance and tax differences (market-dependent)
2) Charging infrastructure economics (site layer)
– Chargers, civils, cabling, switchgear, commissioning
– Grid connection upgrades and ongoing capacity fees (where applicable)
– Software/CPMS costs, connectivity, licenses
– O&M/SLA, spare parts strategy
– Phasing plan (add bays now, add power later)
3) Energy cost layer (operational energy)
– Electricity tariffs: fixed vs TOU vs dynamic
– Demand charges/capacity fee rules (peak measurement)
– Managed charging benefits: peak shaving + TOU shifting
– Public charging share and price (as exception vs primary)
4) Program layer (multi-site scaling)
– Standardization savings across sites (repeatable designs, framework contracts)
– Centralized monitoring and service coverage
– Internal resource costs (project management, training, change management)
– Risk and sensitivity scenarios (grid delays, price swings, utilization)
Core outputs you want from the model
– Payback period (years)
– NPV and IRR (better than payback for long assets)
– €/km (all-in) vs ICE baseline
– Cost per delivered kWh at depot (all-in)
– Peak kW unmanaged vs managed (demand charge exposure)
– Readiness impact (cost of failures/public fallback if uptime is weak)
Typical structure (tabs/blocks)
Inputs
– Fleet: vehicle count by class, km/day, duty cycle, shifts, growth plan
– Vehicles: EV/ICE price, lease terms, maintenance, energy efficiency
– Sites: depot list, capacity limits, charger counts/power, install cost, phasing
– Energy: tariffs, demand charge rules, public charging price and share
– Service: CPMS + SLA pricing, uptime assumptions
– Incentives: grants/rebates, tax benefits (time-bound)
Calculations
– Vehicle energy demand (kWh) = km × kWh/km (with seasonality factor)
– Charging split: depot vs public (affects €/kWh and reliability)
– Site peak modeling: unmanaged vs managed peak kW
– Demand charges/capacity fees based on peak rule
– Annual cashflows: CAPEX + OPEX vs ICE baseline savings
– NPV/IRR using discount rate + asset life
Outputs dashboard
– Payback / NPV / IRR
– €/km and savings breakdown waterfall
– Sensitivity tornado: electricity ±%, diesel ±%, utilization, grid upgrade cost
– “Scale triggers”: when to add chargers or increase capacity
The 5 variables that usually swing ROI the most
– Public charging share (higher share usually hurts ROI fast)
– Grid upgrade cost and lead time (CAPEX + delayed benefits)
– Demand charges/capacity fees driven by unmanaged peak kW
– Energy price spread (diesel €/km vs electricity €/km at depot)
– Utilization / vehicles-per-charger (spreads infra CAPEX)
How to model managed charging correctly (so ROI is realistic)
– Model two cases: unmanaged vs managed
– Include a site cap and hourly charging window shape (arrival/departure wave)
– Translate peak reduction into demand charge/capacity fee savings (if applicable)
– Add CPMS/SLA costs (managed charging isn’t free)
– Add readiness penalty cost if charging uptime is low (public fallback + lost time)
Common ROI modeling mistakes
– Using average kWh/day but ignoring peak kW (demand charges appear later)
– Assuming “everyone charges off-peak” without scheduling discipline
– Leaving out software, connectivity, and service costs
– Underestimating civils/switchgear/trenching costs
– Treating grants as guaranteed and permanent
– Ignoring downtime and the operational cost of missed readiness
Related glossary terms
Fleet charging ROI
Fleet electrification payback
Demand charges
Fleet energy optimization
Fleet charging scheduling
Depot charging