Recognising and managing battery electric bus risks

Electric buses powered by battery packs, recharged at fixed locations such as operating bases or depots, are an increasingly popular choice for transport operators in response to environmental and commercial expectations.

A bus powered solely by a rechargeable battery pack is a zero emissions vehicle, with various grants and schemes having been made available to support both the costs of purchasing the vehicles and their associated recharging infrastructure.¹

However, losses from fires involving battery electric vehicles (BEVs) can be greater than for conventional vehicles. This is because of the way BEV fires develop. As well as the ignition of the conventional fixtures and fittings, additional electrical components, in particular the battery pack, can explode should they ignite, distributing ignited items including individual battery cells over greater areas.

Emergency services are also likely to initially adopt a spread-prevention approach to a BEV fire, rather than fighting the fire directly. This is because of the risk of explosion which could distribute the fire to the surrounding areas, potentially including residential accommodation.

How can electric bus fleet operators manage BEV fire risks?

There are a range of measures transport operators can consider to mitigate and manage the risks associated with electric bus fires, including:

• Installing effective charging and monitoring technology in depots, with telemetry data accurately logged and monitored, thus enabling operators to build a picture of how vehicles are responding to charging, and to compare charging characteristics between buses and against expected parameters in order to detect potentially dangerous anomalies
• Establishing defined processes should a vehicle exhibit unexpected characteristics whilst at the depot, for example, a procedure being in place to move buses to an isolation area for further inspection
• Enhancing the training of drivers, engineers, and technicians to detect, address or escalate electric bus operation and maintenance concerns
• Using additional vehicle inspection methods, including thermal imaging technology in depots to identify ‘hot spots’ in vehicle and depot based systems including battery packs, charge points, cabling and connections
• Documenting and defining effective disaster and incident recovery plans collaboratively with key stakeholders such as other operators, the emergency services, technical specialists and insurers.

Business continuity planning to manage BEV fire risks

The most significant area of risk occurs when electric buses are recharging at depots. Not only will a major incident create a loss of vehicles, but compromise the availability of the charging infrastructure and therefore the ability of an operator to provide a service.

That’s why operators must consider their business interruption provisions directly alongside business continuity plans that define appropriate alternative methods of recharging and consider the requirements for a potentially part-remaining electric bus fleet following an incident.

This is particularly important given that recharging system infrastructures contain sophisticated items which require specialised skills to install, contributing to potentially long lead times.

One way to manage the risks here is greater collaboration with other commercial electric vehicle operators, such as local councils and utility providers, whereby recharging facilities could be shared in an emergency situation.

This would also demonstrate to insurers how your business interruption plans and work-around methods are implementable and would enable your business to recover quickly.

There are further advantages from collaborative approaches to developing business continuity plans. Combined forums provide an opportunity for knowledge, insight and best practice to be shared for the benefit all participating operators.

Managing the on-the-road electric bus risks using telematics

Whilst we focus here on static risks of electric buses, there are opportunities for operators to manage driver behaviours by utilising additional data.

A key driving element of all electric vehicles is the ability of the driver to harvest energy back into the vehicles batteries via regenerative braking systems. This is when the vehicle is slowing down, certain components on the vehicle can harvest deceleration and send energy back into the batteries, thus reducing the need to recharge statically.

Drivers being trained and monitored by telematics utilising this additional data stream, can be encouraged to anticipate and control braking in ways that harvest greater amounts of energy. Such moves could also help reduce the risk of vehicles being involved in collisions.

Next steps for battery electric bus operators

While the level of occurrence of fires involving electric buses is currently low, (with the origin of ignition often not necessarily the electric bus itself), where incidents do occur, the severity is often high, prompting concern amongst insurers.

Operators moving to electric buses need to view these fleets with fresh eyes, recognising that switching to electric vehicles is not as straightforward as simply replacing current vehicles with the same number of electric buses. They must consider, amongst other factors, depot layouts and parking locations in light of the specific fire risks.

Effectively identifying risks and implementing controls and articulating these measures clearly to the insurance market, is also essential.

We also believe it’s vital manufacturers and operators continue to work together to present how electric bus risks are being managed, or potentially face higher insurance costs and wider caveats from an ultimately contracted insurance market.

For expert help managing risk around electric vehicles and other emerging transport risk, get in touch.

Footnote

¹ Zero emission buses: local authority toolkit

Contact

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Andrew Millinship

Practice Leader – Transport Risk

email Email phone +44 0 7764 836 394

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