Energy intensity is a measure of how much energy is used per unit of output. In EV charging and e-mobility, it is commonly used to express electricity consumption relative to distance driven, service delivered, or operational activity, helping fleets and site operators benchmark efficiency, plan costs, and report sustainability performance.
What Is Energy Intensity?
Energy intensity describes the relationship between energy input and a meaningful unit of activity.
– kWh per km (or kWh per 100 km) for vehicles
– kWh per delivery or kWh per route for logistics operations
– kWh per vehicle per day for depots and fleet readiness planning
– kWh per charging session or kWh per charger per day for charging network performance
– kWh per m² (building context) when EV charging is part of facility energy reporting
Lower energy intensity typically indicates higher efficiency—less energy used to achieve the same output.
Why Energy Intensity Matters in EV Charging
Energy intensity enables better operational and financial decisions.
– Helps fleets forecast electricity spend and required charging capacity
– Enables benchmarking between depots, routes, vehicle models, and seasons
– Identifies operational inefficiencies such as excessive idling (aux loads), poor route planning, or underperforming vehicles
– Supports sustainability reporting by linking energy use to service outcomes
– Helps evaluate interventions like driver training, load management, or vehicle right-sizing
Common Energy Intensity Metrics in E-Mobility
Vehicle-focused
– kWh/100 km (most common benchmark)
– kWh/km for route-level precision
– kWh per tonne-km for freight and heavy-duty applications
Charging-site-focused
– kWh per session
– kWh per connector per day/week
– kWh per fleet vehicle per shift
– Peak kW intensity (power demand) per charger cluster for capacity planning
Operational-focused
– kWh per delivery stop
– kWh per operating hour (e.g., municipal vehicles, service fleets)
How Energy Intensity Is Calculated
Energy intensity depends on accurate measurement and a clear denominator.
– Measure energy used: from vehicle telematics, charger data, or site metering
– Define the activity unit: distance, deliveries, time, or sessions
– Calculate: Energy intensity = total kWh ÷ total activity output
– Normalize by comparable conditions (vehicle class, payload, temperature, route type) for fair benchmarking
What Affects Energy Intensity for EV Fleets
Energy intensity varies widely based on operational conditions.
– Vehicle type, weight, aerodynamics, and drivetrain efficiency
– Payload and driving style (acceleration, speed, regenerative braking behavior)
– Route profile: hills, traffic, stop-and-go patterns
– Temperature and HVAC usage (heating/cooling can significantly increase kWh/100 km)
– Tire pressure, maintenance condition, and accessory loads
– Charging losses and battery thermal management (if measuring from the grid rather than vehicle)
Using Energy Intensity to Improve Charging Operations
Energy intensity is especially useful when linked to optimization actions.
– Improve route planning and vehicle allocation to reduce energy per service unit
– Tune charging schedules based on predicted kWh needs per shift
– Size depots based on measured kWh per vehicle per day rather than guesses
– Detect anomalies: sudden increases in kWh/100 km can indicate issues (tires, drivetrain, battery health)
– Support fair internal cost allocation using kWh per route, department, or cost center
Limitations to Consider
– Comparing energy intensity across fleets requires consistent measurement boundaries (vehicle-reported vs grid-metered energy)
– Seasonal effects can dominate results; benchmarking should use comparable time windows
– Mixed duty cycles (urban vs highway) can distort “average” values
– Energy intensity is not the same as carbon intensity—carbon depends on the electricity source and emission factors
Related Glossary Terms
Carbon Intensity
Emission Factors
Energy Consumption Analytics
Fleet Dashboards
Charging Efficiency
Depot Charging
Load Management
Power Quality