Keeping vital vehicles charged: the importance of EV fleet charging SLAs
Overview
For fleet operators, keeping vehicles charged and operational is critical to maintaining efficiency and service delivery. When an electric vehicle (EV) charger fails, the consequences can include delayed deliveries, missed service windows, vehicle downtime, lost revenue, strained customer relationships, breach of contract and brand reputation damage.
Fleet downtime carries a substantial cost – each out-of-service van costs an average £800 per day – and with electric vehicles, a simple failure to charge can leave an otherwise roadworthy vehicle sitting idle in the depot (1). If a wider infrastructure issue takes multiple chargers out of action, the impact can quickly become catastrophic.
Dependable EV fleet charging infrastructure is therefore a prerequisite to transitioning to an electric fleet. And once installed, it’s essential that any solution is backed by robust support agreements. This ensures rapid and proactive support – maximising charger uptime and reliability, and minimising the impact of any faults.
Service level agreements – what they are and why you need them
Businesses can avoid the pitfalls of failed charging with a fixed service, maintenance and repair agreement. Usually referred to as a service level agreement (SLA), this contract is an agreed framework within which a service provider like Mer will respond to issues. In the case of tailored aftercare for EV fleets, an SLA can wrap proactive inspection and firmware updates, maintenance, and emergency fault repair into a single convenient contract managed by a single expert provider. For fleet operators, SLAs are typically delivered by a commercial EV charging provider responsible for infrastructure uptime, monitoring and aftercare.
SLAs set clear performance metrics for maintenance and repair timelines, along with maximum downtime limits. Having an SLA in place gives fleet operators the reassurance that issues will be resolved within an agreed timescale, so they know when repairs will be completed, and can plan in appropriate contingency arrangements.
However, not all depots are the same, so it makes sense to ensure that EV infrastructure support is tailored to your organisational needs. Where high availability and fast vehicle turnarounds are imperative, SLA targets can be strict. But where charging isn’t as time sensitive, agreeing longer callout or repair times can allow lower costs, or an increased emphasis on preventative maintenance.
Last-mile delivery EV fleets: SLA requirements
Because last-mile fleets typically operate on predictable schedules, their EV charging SLAs can prioritise proactive maintenance and next-day response rather than immediate call-outs. Regular scheduled servicing, combined with smart monitoring systems that identify potential issues during off-peak hours, can prevent many service disruptions and offer better value than round-the-clock emergency coverage.
This comparative flexibility means that last-mile operators may choose to focus their fleet depot charging SLAs on proactive maintenance and performance monitoring, rather than immediate reactive response. At the same time, last-mile delivery vehicles represent direct revenue generation, so even modest improvements in charger uptime for fleets translate to measurable financial benefits.
Emergency services EV fleets: 24/7 SLA requirements
For emergency services, any charging downtime carries operational risk, which is why SLAs must focus on 24/7 availability, rapid response times and continuous monitoring. Ultra-fast chargers can fully charge some emergency vehicles in as little as 30 minutes, but this capability is only valuable if the chargers are operational when needed – which could be at any time, and with just moments’ notice.
For these fleets, 24/7 EV charging support is essential. SLAs need to offer clear response time commitments, and sufficient engineering coverage across operational areas. But proactive charger monitoring forms another critical component for emergency services EV charging. Systems that detect performance degradation – such as declining charging speeds, increasing error rates or power supply irregularities – enable scheduled maintenance during planned downtime, rather than emergency repairs during critical periods.
Designing SLAs around operational risk
Effective SLAs begin with an understanding of operational risk. That means understanding the true impact of vehicle unavailability on the organisation – not just in revenue loss, but in cascading impacts such as customer SLA breaches, reputational effects or the expense of maintaining backup capacity. Once these costs are understood, it’s easy to see which SLA parameters are key for the business.
An emergency service can justify the value of 24/7 EV charging support for critical fleets, and its investments in infrastructure redundancy. A delivery fleet operating five days per week may achieve better value from comprehensive proactive monitoring, combined with next-business-day response guarantees.
At Mer, we build EV fleet charging support around your specific operational patterns, assessing downtime risk, and designing robust EV fleet charging SLAs that keep vehicles operational while managing costs appropriately. Our approach combines infrastructure planning, proactive charger monitoring to reduce unplanned downtime, and responsive support tailored to each fleet’s requirements. That’s why 99% of our customers renew their service agreements with us.
One-size-fits-all SLAs don’t work for EV fleets. Effective EV fleet charging support starts with understanding operational risk and designing aftercare around how vehicles are actually used. By tailoring SLAs to fleet needs, operators can reduce downtime, protect service delivery and manage costs more effectively.
Find out more
Ready to develop charging infrastructure that supports your operational requirements? Download our comprehensive depot charging e-guide for detailed guidance on planning, implementing, and maintaining fleet charging infrastructure.
