Time-based pricing is an EV charging tariff approach where the cost of charging depends on time, not only energy delivered. It can mean:
– A direct time tariff (€/minute or €/hour) for charging or plug-in duration
– Time-dependent prices (different rates at different times of day, such as peak vs off-peak)
– Time-based fees layered on top of energy pricing (for example idle fees after charging completes)
Time-based pricing is used to influence behavior, manage congestion, and align charging with grid and site constraints.
Why Time-based Pricing Is Used
Time-based pricing is commonly applied to:
– Improve bay turnover at busy sites (discourage long occupancy)
– Encourage off-peak charging to reduce peak demand and energy costs
– Support managed charging and grid-friendly behavior
– Balance fairness and operational control when charging speeds vary by vehicle
– Improve site economics where parking space is scarce and valuable
Common Forms of Time-based Pricing
Per-minute / per-hour charging tariffs
– Users pay based on time spent charging or connected
– Often used where congestion management is more important than strict €/kWh fairness
– Can be applied only during active charging or across full plug-in time
Idle fee pricing
– A time-based fee after charging completes, often with a grace period
– Designed to keep bays available and reduce blocking behavior
– May escalate the longer a vehicle remains connected
Time-of-use (TOU) pricing
– Prices vary by time window (peak vs off-peak)
– Used to shift charging demand to cheaper and lower-carbon periods
– Common in fleet depots and multi-tenant sites with predictable schedules
Tiered time pricing
– Rate changes after a threshold (e.g., first 60 minutes cheaper, then higher)
– Used to reward short top-ups and discourage long stays
Event-based time pricing
– Temporary pricing rules during high-demand periods, events, or congestion
– Used for special operational control in public hubs
Benefits of Time-based Pricing
– Helps manage congestion and improves bay turnover
– Encourages load shifting, reducing peak demand impact
– Can improve charger availability and customer experience at busy sites
– Supports operational goals in retail and urban sites where dwell time matters
– Provides an additional control lever alongside load management
Limitations and Fairness Considerations
Time-based pricing can create perceived unfairness because power is not constant:
– Different vehicles charge at different power due to onboard limits
– Charging slows at high State of Charge (SoC), raising cost per kWh
– Temperature derating or site load management can reduce power, increasing cost per kWh
– Users may feel penalized for conditions they cannot control
Because of this, many operators use time-based pricing mainly for idle management and TOU incentives, while relying on per-kWh billing for core energy pricing where feasible.
Best Practices for Using Time-based Pricing
– Clearly explain whether billing is for charging time, plug-in time, or post-charge time
– Use idle fees with grace periods to avoid negative customer reactions
– Combine TOU incentives with messaging to encourage off-peak behavior
– Avoid penalizing users when site limits or derating reduce charging speed (policy design)
– Monitor utilization, complaints, and throughput and adjust pricing rules over time
Related Glossary Terms
Time-based Billing
Per-minute Billing
Idle Fee Policy
Time-of-use Tariffs
Tariff Structures
Tariffs
State of Charge (SoC)
Load Management
Managed Charging