The rapid adoption of electric vehicles (EVs) is undoubtedly positive for our planet’s transition from fossil fuels, but they come with a whole new set of risks to people and property. It is now essential that commercial building developers, owners, and operators work together to fully understand the unique risks of EVs and put measures in place to mitigate them. One such risk is that of fire.
Do EVs pose a greater fire risk than internal combustion engine (ICE) vehicles?
Research in 2022 by the Swedish Civil Contingencies Agency (MSB) revealed that contrary to the media perception, ICE vehicles are around 20 times more likely to catch fire than electric-powered versions. The risk with EV cars is not in the likelihood of fire; it is that if fire takes hold, it poses a much bigger risk to people and property.
EV fires are characterised by extremely high temperatures, thermal runaway, and explosions, which, if they occur within a building or underground (e.g. a hotel underground car park), can cause serious and costly damage to buildings.
Where an internal or underground EV fire takes hold, there is a greater risk of heat, smoke, high temperature, and the fire spreading. It can also be much more difficult and dangerous to enter basements and underground car parks, potentially hampering efforts to extinguish EV fires.
What is ‘thermal runaway’?
‘Thermal runaway’ is a risk associated with lithium-ion batteries, whereby the cells enter an uncontrollable, self-heating state, resulting in the ejection of gas, shrapnel, extremely high temperatures, smoke, and ultimately fire. An EV fire typically results in a heat release rate (HRR) of 1 MW, but an EV battery fire may have values of more like 5 – 7 MW. Research shows that a higher state of charge also corresponds to a more rapid total energy release and a higher peak energy release rate. In other words, the more charged the battery, the more intense the fire.
Mitigating the risk of EV fires in commercial buildings
With careful planning and design, there is much that commercial building stakeholders can do to reduce the risk of damage from EV fires. Some of the key EV fire risk mitigation measures are as follows:
Installation and location of EV charging infrastructure
- For external EV charging infrastructure, ensure that combustible materials are at least 10m away and non-combustible materials are at least 7.5m away from EV chargers. Combustible materials include fuel pellets, gas cylinders, and waste materials.
- Make sure that EV chargers are physically protected from being hit by vehicles (e.g. by drivers reversing into a car parking space).
- Make use of any existing ventilation (including natural ventilation) when deciding where to locate EV chargers within buildings. Ventilation will ensure that toxic gases can escape.
- Ensure that, where possible, all EV chargers are located in one place. This makes the task of mitigating EV fire risks easier to manage.
- EV chargers should always be installed onto non-combustible surfaces.
- Ensure that your EV charger installers are suitably certified engineers, e.g. by the National Inspection Council for Electrical Installation Contracting (NICEIC).
- Ensure that flood water cannot come into contact with EV chargers.
- Have adequate on-site security to prevent the theft of metals / EV cables.
Fire suppression and extinguishing
- For internal and underground EV infrastructure, sprinklers must be installed to control and suppress any fire that breaks out. Building insurers typically require the installation of sprinklers and fire detection equipment for existing unprotected car parks as a key EV fire mitigation measure.
- EV chargers should be turned off automatically in the event of a fire – this is a requirement to allow fire services to gain access. The fire alarm and sprinkler system should activate the switch-off mechanism.
- Install rear fire exits to allow firefighters to gain access.
- Consider how you can ‘compartmentalise’ any area where EV chargers are located. Being able to close off EV charging areas in the event of a fire will reduce the risk of damage to the wider building. Hot concrete can spall when in direct contact with fire fighting water spray, leading to building collapse. Aim for 60 – 120 minutes of fire resistance in basement car parks where possible.
Maintenance and servicing
- Ensure that you have a maintenance and servicing contract in place to check the EV chargers in your building are operating correctly and in a safe condition.
- Have a system/process in place for reporting and actioning any repairs to your EV charging infrastructure.
- Have residual current devices (RCD) attached to your EV charging infrastructure tested every year for correct operation and safety. This must be monitored by a professional maintenance company.
- Consider the additional servicing and maintenance requirements of EV charging infrastructure, including electrical inverters.
Other considerations for e-bikes and e-scooters
- While e-bikes and e-scooters typically have a lower voltage, there is a higher risk of batteries purchased from other countries for retrofitting, which do not meet the required quality kitemark standards. In addition, such vehicles are often immediately charged after being used without allowing time for the battery to cool to a safe temperature, leading to a higher risk of thermal runaway.
- E-bikes and e-scooter charges should not be permitted in hallways, fire escapes, or other unsuitable places lacking fire mitigation measures. This can be a particular problem in apartments or blocks of flats with large number of occupied apartments. Place warning signage where necessary to prevent this from happening.
- Multi-plug adapters should never be used for charging e-bikes and e-scooters.
- It should be part of the role of managing agents and concierges to check for the safety of e-bikes and e-scooter charging, i.e. keeping fire exits free of obstruction and for signs of charging cable fraying/damage.
- Have a system in place to allow tenants to report issues relating to charging infrastructure problems and ensure these are actioned promptly.
Final words
There are a broad range of risks relating to EV charging infrastructure within commercial buildings, but there are also many ways to mitigate them. The key message is that from the commercial building insurance perspective, stakeholders should continually carry out risk assessments of their EV charging infrastructure and take prompt action where necessary. Doing so will reduce insurance premiums and ensure that claims are approved and paid without delay.
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This article was adapted from an article by Zurich which can be found here.