Electric car batteries behave differently when they catch fire than when petrol or diesel cars catch fire. As the number of electric cars continues to increase, developers and parking operators are challenged to switch to new technologies to prevent and extinguish this new type of fire. Fortunately, science and the private sector have come together to deliver a solution. This is water mist extinguishing technology , supplied in Slovakia by 3MON. Water mist protected parking houses offer enhanced fire safety while minimizing water damage.
Theoretically, almost every third car we come across in any car park is electric or has a hybrid drive. In fact, the current sales of electric cars in the European Union correspond to such figures. And the number is set to increase, as the European Parliament has definitively approved a ban on the sale of ‘internal combustion’ cars from 2035. Insurance companies are also reacting to this fact by increasingly requiring developers to obtain a so-called VDS certificate, which requires the deployment of fire protection technologies that can also cope with the crashing of parked electric cars.
Challenging to extinguish
Technical faults, mechanical damage, neglected diagnostics. These are also reasons why the battery in an electric car can catch fire and cause a fire. The result is less fire but extremely high levels of toxic smoke and high temperatures that are difficult to reduce. In an incident in an underground garage in Prague in early May, firefighters complicated their response to a burning electric luxury car. They had to use cobra technology, which is actually a powerful jet of water that literally cuts its way up to the battery to cool and extinguish it. The current practice is to submerge the electric car in a water bath and wait for the temperature to drop.
Burners are extinguished with foam, but that doesn’t help with electric cars. When an electric car catches fire, it is necessary to start extinguishing the fire at the first stage when it starts, because by the time firefighters arrive on the scene, up to 10 minutes will have passed. By then the premises are usually already engulfed in fire, along with all the flammable substances. At that point, the only thing to do is to cool the electric vehicle, push the combustion products out of the area, secure and protect the other fire compartments and evacuate the premises. Ordinary water, more precisely water mist, proved to be the best for this first phase.
Parking houses, whether they are part of, for example, shopping centres or office buildings, are often equipped with classic sprinklers. However, in the event of a fire, they release so much water that they can flood an entire floor and the damage to the building owner is significant. In addition, these systems are less effective against EV fires and therefore risk causing irreversible damage to the building’s structure before the fire can be extinguished.
In testing, they let the electric car burn for over seven minutes. The temperature rose to 880 ˚C. After activating the nozzles, the thermal imaging cameras recorded a significant temperature reduction after just one and a half minutes.
Under the protection of water mist
The answer is the use of water mist extinguishing technology supplied by 3MON to the address market. It was developed by the Danish Fire and Safety Technology Institute (DBI) together with the Danish company VID Firekill. For underground or other closed garages, a static system of special nozzles is most suitable. These have a highly reliable fire detection capability and in an instant disperse a water mist onto the ignited electric car and, of course, onto the surrounding vehicles. It is these micro particles of water that have the ability to absorb the enormous amount of heat converted into steam. Just one litre of water dissipates up to 1.64 cubic metres. This uses half the water of conventional sprinklers. As it is essential to reduce the temperature of electric cars, water mist has proven to be extremely effective.
In testing, they let the electric car burn for over seven minutes. The temperature rose to 880 ˚C. After activating the nozzles, the thermal imaging cameras recorded a significant reduction in temperature after just one and a half minutes, with the temperature of the electric car droppingto just 70˚C in less than 15 minutesand to 30˚C in another 15 minutes. Water mist technology has been shown to have an extraordinary ability to reduce temperature while taking away oxygen from the surroundings thereby taking away the fire’s initial momentum and overall potential.
The demonstration also proved that by using a minimum of water, it is possible to protect surrounding cars; moreover, water mist also works on cars with internal combustion engines. The technology also has strong potential in the prevention and extinguishing of car battery depots and data centres.
