Interval metering is the measurement and recording of electricity usage in fixed time blocks (intervals) such as 15 minutes, 30 minutes, or 60 minutes, instead of only providing a single cumulative meter reading. In EV charging, interval metering enables more accurate cost allocation, demand analysis, and advanced energy use cases like load management, tariff optimization, and granular reporting for fleets and multi-site operators.
What Is Interval Metering?
Interval metering captures how much energy (kWh) is used during each time window:
– Example: kWh consumed from 08:00–08:15, 08:15–08:30, etc.
– Data is stored as a time series, often with timestamps and quality flags
– Interval lengths depend on the meter, utility requirements, and reporting needs
This is commonly delivered through smart meters, submeters, or site energy monitoring systems.
Why Interval Metering Matters for EV Charging
EV charging loads are highly time-dependent. Interval metering helps operators and site owners:
– Understand peak periods and charging behavior patterns
– Quantify demand charges exposure and peak demand drivers
– Verify the effect of load balancing and power throttling policies
– Allocate costs between tenants, departments, or user groups more fairly
– Support billing reconciliation and audit-ready reporting
– Enable advanced sustainability reporting such as hourly matching approaches
For depots and commercial sites, interval data is often the difference between “guessing” and managing energy performance precisely.
How Interval Metering Is Used in Practice
Common EV charging use cases include:
– Site power capping: ensuring total load stays under import capacity
– Demand management: identifying and reducing short peak spikes that trigger demand charges
– Time-of-use optimization: shifting charging to lower-cost tariff windows
– Fleet readiness planning: linking charging profiles to departure schedules
– Fault detection: spotting abnormal consumption when chargers appear idle (idle power consumption)
– Portfolio analytics: comparing performance across multiple sites with consistent time granularity
Interval Metering vs Billing Metering
These concepts are related but not identical:
– Interval metering refers to time-granular measurement and logging
– Billing metering refers to metering that is legally accepted for customer billing (often requiring certification, e.g., MID metering in many EU contexts)
A meter can be interval-capable and also billing-grade, but not all interval meters are compliant for regulated billing.
Typical Interval Lengths
Common interval settings include:
– 15-minute intervals (common for demand and utility settlement)
– 30-minute intervals (common in some markets and reporting systems)
– 60-minute intervals (common for simplified analytics and hourly matching)
Shorter intervals provide more detail but increase data volume and integration requirements.
Data Quality and Integration Considerations
Interval metering is only valuable if data is reliable and consistent:
– Accurate time synchronization (time zone and daylight savings handling)
– Clear mapping between meter channels and charger circuits
– Data completeness (handling gaps, backfill rules, estimated intervals)
– Secure data transfer and storage for auditability
– Alignment with CPMS session timestamps for analysis and billing reconciliation
Related Glossary Terms
Smart Metering
Submetering
MID Metering
Demand Charges
Time-of-Use (TOU) Tariffs
Load Balancing
Power Throttling
Import Capacity
Hourly Matching
Idle Power Consumption