All About Series | May 30, 2023
All About Service Level Agreements (SLAs) for Electric School Buses and Chargers

SLAs can provide school districts and fleet operators with a road map in case issues with operations and maintenance pop up. Here’s what to know.

An electric school bus charges in a parking lot.

Reliability is essential for any school district’s school bus fleet. Reliable operations require, among other things, prompt responses to any issues that arise. This is true for operations regardless of fuel type, but especially as districts integrate and get used to a new technology such as electric school buses. 

This is where service-level agreements (SLAs) come in. 

What are SLAs?

An SLA is an agreement between a customer and vendor that covers products’ operations and maintenance. SLAs can come in many forms and are used across many industries. SLAs detail what kind of service can be expected and specify minimum thresholds for the time that a product should be functioning properly (also known as “uptime”). For electric school buses they should cover both the vehicle and charging operations, although different parties may be involved.

SLAs are very common in the IT industry, where an agreement may stipulate that the service provider must ensure the software functions 98% of the time, for example. When it comes to electric school buses, SLAs can stipulate that buses and chargers are operating as needed and include backup plans and sometimes even compensation if the issue cannot be fixed within a specified timeframe.

It is important to be clear about what is and is not covered by an SLA. Clearly stating what repairs are covered, who is responsible for them and the expected timeline for the repairs in an SLA can help minimize disruptions to operations. 

SLAs differ from warranties in that warranties focus on guaranteeing equipment, while SLAs detail the service that will be provided. SLAs provide another layer of guarantee in addition to a warranty, and a good SLA will cover any gaps between what the warranty covers and what is required for successful operation of the product.

There are multiple entities involved in the successful operation of electric school buses (see image below). SLAs simplify operations and maintenance by streamlining the points of contact and clarifying responsibilities for the parties involved — saving time when issues arise.

A diagram showing roles within school bus management

Electric school bus vehicle SLA recommendations

Which parties should be included in the SLA?

SLAs for vehicles should be between the fleet operator and the vehicle dealer or manufacturer. In most cases, dealers are your local experts on your buses and are the best point of contact if any issues arise. One of the benefits of an SLA is that it establishes one point of contact for when an issue occurs, simplifying and usually speeding up the repair process.

What parameters should be included in the SLA?

  1. Length of agreement – vehicle SLAs’ coverage period should at least match the length of the maintenance warranty.
  2. Service response time – vehicle SLAs should stipulate a response time that the district or fleet operator is comfortable with. This could cover both a response time to have a technician onsite or virtually diagnose the issue, as well as a time to have an issue in service for a repair. 
  3. Uptime guarantee – vehicle SLAs should specify how long a bus may be down or out of service for reasons outside of an accident. If the bus is out of commission for longer than this time, the dealer should provide the fleet operator with a replacement bus or pay a specified daily penalty, sometimes called liquidated damages. This penalty should cover the costs of filling in the gap caused by the bus being out of commission. If the issue is not resolved within a specified time period, such as 90 days, the dealer should further compensate the fleet operator for costs incurred by the disruption. Alternatively, the SLA can specify a minimum number of available functioning buses at any one time. In this case, the service provider (i.e. the dealer or manufacturer) is responsible for having contingency plans in place to ensure the agreed upon level of service.
  4. Training – vehicle SLAs could also detail what level of training the dealer or manufacturer will provide for the fleet operators’ drivers, mechanics, and others who will be working with the buses. Effective use of regenerative braking while driving has a significant impact on battery range, so it is important for drivers to learn best practices when driving electric school buses. Similarly, having trained mechanics on staff can help fleet operators resolve issues more quickly and reduce bus downtime. Training can include both online and in-person courses. In-person training is particularly important for teaching safety procedures. The duration of the training programs can vary from hours to weeks depending on the chosen level of training. It can be helpful to have some level of training available and access to any online materials for the duration of the SLA.
  5. Other: 
    1. Vehicle SLAs should specify a local service center, within an agreed upon range, to ensure that maintenance issues can be handled in a timely manner.
    2. These agreements should also include timelines for the availability of parts and penalties if these timelines are not met. The penalty should be sufficient to cover the cost of correcting the issue.
    3. Vehicle manufacturers should be required to provide all reasonable assistance to the network provider (see below) to diagnose and correct any issues with vehicle charging.

Electric school bus charger SLA recommendations

Which parties should be included in the SLA?

Charger SLAs should be between the fleet operator and whichever entity is managing your fleet’s charging, known as a network provider. In some cases, the manufacturer of your charger may also serve as the network provider. In other cases, you might procure chargers from a manufacturer and then work with a third-party provider to manage your charging and serve as the network provider. Either way, the network provider should be responsible for the full operation and maintenance of the charger and the network. 

In the case where the manufacturer and network provider are separate entities, the network provider should be responsible for any necessary communications with the charger manufacturer to fix any problems. This allows for a single point of contact when addressing issues with a charger. This is typically more efficient than having the fleet operator communicate between the two parties. 

An SLA with the network provider is preferable to relying on the manufacturer warranty because network providers have access to historical data that may be necessary to diagnose the problem.

What parameters should be included?

  1. Length of agreement – charger SLAs should be for up to five years with termination clauses for poor performance. This way, the fleet operator is not locked into using a specific contractor if things do not go well. Determination of poor performance should be up to the fleet operator. Upon determining that performance has been unsatisfactory, the fleet operator should provide notice to the service provider detailing specific issues and allowing a reasonable amount of time (such as 10 days) to fix those issues.
  2. Service response time – charger SLAs should cover four levels of response time:
    1. Emergency service: In the case of an emergency, charger SLAs should require that the issue be addressed within 24 hours. Emergency service is generally required if a maintenance issue is affecting fleet operators’ operations more broadly. For example, if a charging handle is plugged into a bus and its locking mechanism will not disengage to allow unplugging, rendering both the charger and bus unusable, this rises to the level of emergency service.
    2. Scheduled service: If a charger is not functioning properly and requires scheduled service, charger SLAs typically call for a response time of the next workday after 8 hours notice.
    3. Ongoing maintenance, repair and software updates: Beyond scheduled service to address specific issues, charger SLAs should also require ongoing maintenance, repair, and updates on an annual or semiannual basis. At a minimum, this type of maintenance checks the entire charging system and ensures it is functioning properly.
    4. Firmware updates: Charger SLAs should require that the charger manufacturer conduct firmware updates as these updates are released, not just when scheduled or ongoing service takes place. These updates often involve security fixes, so it is important that the chargers are updated in a timely manner. These updates must be coordinated between the manufacturer and the network service provider.
  3. Uptime requirements – ideally charger SLAs should stipulate an uptime of greater than 97% (the minimum uptime requirement recommended by the Federal Highway Administration’s National Electric Vehicle Infrastructure Program). Uptime is the amount of time the charger is available for use outside of scheduled maintenance and repair or outside events like grid outages or natural disasters. This guarantee should cover uptime rates for each individual charger, not just the system as a whole. Network providers should report uptime rates and causes of downtime to the customer to maintain transparency and accountability. Certain events that affect charger operations, such as scheduled maintenance, catastrophic weather events or electricity grid or wireless network failures, will likely be excluded from uptime calculations. Therefore, SLAs should clearly state how uptime is defined and calculated.
  4. Training – fleet operators should assess any additional training needs beyond what is already offered and include those in their charger SLAs. Training could cover charger operations, maintenance and troubleshooting, as well as any portals or dashboards used to collect and display data on charger performance.
  5. Other – charger SLAs should identify a local contractor with experience installing, maintaining and repairing electric vehicle chargers, as well as experience working on high-voltage equipment. Local should be classified as within a 50- to 100-mile radius, depending on the fleet operator’s locale (urban, suburban, rural, etc.).

When vehicle and charger issues overlap

To avoid issues arising from incompatible equipment, both the charger and vehicle manufacturers should sign a commissioning checklist that certifies that the chosen charger, bus and network are compatible prior to a school district approving final invoice payments and accepting the bus, charger and network provider. For example, 20% of the invoiced amount can be withheld as contingency until the system is working as contracted. Upon successful commissioning of the system, the district or fleet operator would release the 20% contingency for final payment.

There may be situations where a charger is plugged into a bus, but the bus is not receiving charge. In such a case, it may be unclear what is causing the issue and whether it is related to the vehicle or charger. In these cases, it is recommended that the charging network provider be responsible for fixing the issue, as the network provider has the best access to data to diagnose the problem. However, the vehicle manufacturer must also be required to provide the network provider with all reasonable assistance with the issue.


Disclaimer: These recommendations were developed by World Resources Institute’s Electric School Bus Initiative based on the experiences of school districts. These recommendations are intended to provide general guidance and should be used for informational purposes only. We do not expect credit or citation for any of this material.  Any information in this article should be used at your own risk. WRI makes no warranties or representations about the completeness or accuracy of this information and assumes no responsibility for any consequences of your use of these materials. You should consult with your legal advisor regarding compliance with all applicable laws and regulations.

Briana Fowler-Puja