Answer guide · English

By Symbioen · Published · Reviewed

What Should an EV Charging Service-Level Agreement Measure?

Keep operator-reported uptime in the EV charging service-level agreement (SLA) — then add the three things it cannot see: whether charging actually succeeds, how fast faults get cleared, and how much of the network produced usable evidence at all. Every result needs its period, denominator, exclusions and source written down, or the two parties will calculate the same clause differently and both be right.

Use case
Procurement, operations and portfolio oversight
Base unit
EVSE (one charging point)
Independent baseline
Public National Access Point status history
Boundary
Operational evidence, not legal certification

Six measures for a stronger charging SLA

Public EV charger availability
Was the charging point in a working status?
Working statuses, observed time and permitted exclusions
Successful charging sessions
Did observed charging start and continue?
Session definition and whether status, operator or vehicle data is used
Failure and recovery
How often did service fail, and for how long?
Failure start, recovery rule and maximum restoration time
Signal quality
Is the source timely and stable enough to trust?
Missing, duplicate, delayed and rapidly changing statuses
Utilization
How much observed time showed active charging?
Demand context; low use must not be counted as a fault
Evidence coverage
How much of the contracted network was measurable?
Eligible charging points divided by all in-scope charging points

Organise the SLA around three questions

Availability and successful charging sessions describe the service that was delivered. Failure frequency and recovery time describe how the operator responded when it was not. Signal quality and evidence coverage answer a third question that contracts routinely skip: does the reported result actually represent the network you contracted for? Utilisation sits outside all three as context — a quiet charger is not a broken one, and no SLA should treat it as one.

Define the calculation before setting a target

A percentage is enforceable only when both parties can reproduce it from the same inputs. So name the calculation method and its version in the contract, along with the reporting period, the base unit, the minimum evidence and the exclusions you will allow. Agree the target after that, not before — a number set without its definition is a negotiation you will have again later.

  • State which charging points and hours are in scope.
  • List the statuses counted as working or failed.
  • Define planned maintenance and missing-data treatment.
  • Set the minimum evidence required to publish a result.
  • Require charging-point results as well as the portfolio average.

Choose evidence that matches the decision

Public National Access Point data gives you a baseline that applies consistently across networks and belongs to neither party. Operator session and maintenance records verify outcomes and interventions far more directly, and fleet or vehicle data supplied with consent adds what the driver met at the charger. Report each source on its own before you compare them; a blended figure hides exactly the disagreement you are paying to find.

Keep the compliance boundary clear

Traceable operational evidence can support procurement, SLA monitoring and regulatory reporting. It does not by itself provide legal certification or prove compliance with every contractual or regulatory obligation.

Evidence and method

Sources for this guide