Electric vehicles (EVs) have fewer components compared to gasoline vehicles and are generally simpler to repair. However, under different conditions and especially in the wet season, many are concerned about the reliability of EVs in flood situations. Despite lacking an engine, EVs are actually quite sensitive to water. In this Kwiksure article, we’ll share important precautions for driving an EV in a flood and how to handle water-related issues afterwards.

Electric Vehicles in a Flood: What Happens to the Battery and Motor?

When a gasoline vehicle is flooded, water can enter the engine cylinders via the exhaust pipe, causing breakdown and rendering the vehicle inoperable. Although EVs do not face this particular issue, their internal components mainly consist of batteries, motors, electronic control units, and numerous wires. If any of these components are exposed to water, problems can arise.

The National Highway Traffic Safety Administration (NHTSA) of the United States advises that vehicles equipped with lithium-ion battery packs, after being submerged in water, should be kept at least 50 feet away from any buildings, vehicles, or flammable materials. This precaution is crucial for preventing short circuits from causing fires. For EVs heavily reliant on electronic control systems, exposure to water can affect different components differently:

• Battery: It is the core component of EVs, and water entering the battery module can result in short circuits, damage, or even fires.
• Motor: Water entering the motor can cause corrosion or short circuits, affecting the motor's power output.
• Electronic Control Unit (ECU): The ECU is responsible for managing the various functions of the EV, exposure to water can lead to malfunctions or complete failure.
• Wiring and Connections: Water exposure can cause short circuits, connector oxidation, affecting the vehicle's electrical power and signal transmission.

Electric Vehicles and Floods | Consequences of Driving Through Water Can Vary

Given that EVs do not have breakdown issues, owners tend to drive through water without thinking about it. However, few manufacturers specify the waterproof capabilities of their EVs, making it challenging for drivers to assess the risks. While immediate issues might not surface if vehicle components are exposed to water, oxidation or short circuits can occur over time, leading to anomalies in the vehicle's electronic systems.

Generally, if the electronic components of an EV are exposed to water, signs of damage may appear about 8 to 10 days later. Owners should pay close attention to their vehicle's condition for any abnormalities.

Electric Vehicles and Floods | Dealing with Flooded Roads

Although road conditions in Hong Kong are usually satisfactory, if you encounter flooding in unfamiliar areas and you have no idea how deep the water is, extra caution is still called for. If you must drive through the water, maintain a steady speed since it helps reduce the time the vehicle is in water. Although batteries are designed to be waterproof, extended submersion can still result in water seeping into them. Typically, water levels below one-third of the tire height are safe, but it ultimately depends on the vehicle type—sports cars with low ground clearance require extra caution.

Electric Vehicles and Floods | Handling of Two Specific Situations

In the unfortunate event of your EV being submerged in flood water, the proper response depends on the extent of submersion. For instance, if the vehicle is parked when it is flooded, since most electrical systems are likely off, you should not start the vehicle. Instead, promptly call a tow truck to take your vehicle to a repair facility for inspection by a mechanic.

If your vehicle encounters flooding while being driven, personal safety should be your top priority and you should leave the vehicle if necessary. Circumstances permitting, you can move the vehicle to a safe location, and arrange for a tow truck to transport the vehicle for repairs once the water recedes.

While EVs are simpler in design compared to gasoline cars, the differences are mostly confined to the shift from traditional engines to batteries and electric motors. Thus, damage assessment and handling methods for flooding that affects the cabin are quite similar, and can be based on a six-level water damage assessment scale.

Electric Vehicles and Floods | Will Insurance Cover it?

In most cases, comprehensive car insurance offers protection against severe weather conditions. However, third-party insurance does not safeguard your vehicle. In other words, adverse weather is not excluded in car insurance policies. Whether your car is crushed by a heavy object while parked, hit by a fallen tree, has its windows shattered by a large stone, or even gets blown over by the wind, repair costs will be reimbursed according to actual expenses. If your car is flooded and deemed a total loss, insurance companies typically will compensate based on its depreciated market value. Depreciation calculations usually consider factors like the age of the vehicle and its mileage.

Like other types of claims, when you file a claim with your insurance company, you will need to pay a deductible (if applicable). Additionally, because of your claim, your No Claim Discount (NCD) will be reduced, potentially leading to increased car insurance premiums the following year.

Electric Vehicles and Floods | Is it Covered by Comprehensive Car Insurance?

When considering whether to compensate, insurance companies will consider whether the policyholder has taken all reasonable steps to "protect the car from typhoon damage." For instance, if a car owner knowingly drives through flooded areas or drives to the coast to watch the waves despite the risks, it may be deemed as inadequate protection of the vehicle. If the insurance company believes that you intentionally put your vehicle at risk, they may reject your claim altogether. Methods to protect the vehicle include:

• Avoiding driving in severe weather conditions unless absolutely necessary
• Using headlights when visibility is low
• Avoiding parking in areas prone to flooding or mudslides
• Ensuring all windows and doors are properly closed

Please note that the above information is for reference only. Since different insurance plans have varying coverage, it is essential to carefully read the terms and conditions of your insurance policy.