Electric vehicle fires are very rare. The risk for petrol and diesel vehicles is at least 20 times higher
Electric vehicle fires are very rare. The risk for petrol and diesel vehicles is at least 20 times higher
Reports of electric vehicle fires might lead some people to fear the growing numbers of these vehicles will increase fire risk. In fact, replacing petrol and diesel vehicles is likely to reduce it.
I thought that the media was a little over the top with reporting every electric car fire.
Little did I realise just how blown out of proportion it was:
"...electric vehicle battery fires are rare. Indeed, the available data indicate the fire risk is between 20 and 80 times greater for petrol and diesel vehicles. "
The only thing to consider is that EVs have the possibility to catch fire when they are "passively" sitting unattended in your garage under charge, whereas liquid fuelled vehicles are more likely to catch fire in active use when everything is hot and things are being pumped around and someone is at the controls that can notice what's going on and take immediate action.
So a petrol car can sit in the garage with the ignition off and very little is happening electrically (or chemically).
An electric car will be sitting in someone's garage getting 5+ kW pumped into it for 3 to 10 hours overnight, every night. That's a lot of energy getting manipulated via charging circuits and going into a large box of reactive chemistry in the car.
Now all that needs to happen is that quality components are used and electrical standards are followed and some practical things like interconnected smoke alarms are used. In Australia that's mostly par for the course so it's not a huge concern.
But the risk of a house fire in the wee small hours is definitely increased. Doing a quick thought experiment, you can pull a tiny chance out of thin air, like "an EV (or it's charging system in the home) will catch fire while charging overnight once every hundred million times" and say, "imagine if there are a million electric cars in Australia", and the net result is someone's house burning down every three months. The media will be all over that shit if that happens, so car manufacturers and standards bodies have to really work at making that risk almost unimaginably tiny.
You know that petrol cars have electrical systems and batteries too, right?
Electrical issues are one of the bigger causes of petrol vehicle fires, and they don't need the engine to be running. Those vehicles also have a large amount of dangerous chemistry inside them, but that's somehow not a problem.
I'm an auto electrician by trade and I have been for 30 years. I do happen to know quite a bit about wiring on motor vehicles.
The difference I was highlighting is that a petrol/diesel vehicle parked with the ignition off is basically passive. It's very rare for a switched off fossil fuelled car to catch fire by itself after a few minutes have passed since you've turned it off. Fuel is shut off, nearly all circuits are off, anything still actively powered at that point draws milliamps and will be protected by fusing in the 5-10 amp range , and any spontaneous electrical faults (from eg rats gnawing wiring) will be contained as a result. Critical high current wiring for your starter is routed away from points where it can short out if disturbed by said rats, your alternator wiring is protected by fusible links, and finally, your 12 volt battery has a quite limited capacity (in the 0.5-1kWhr range, if we want to compare it to an EV).
And then you have an electric vehicle which when "off" in your garage will have at least several kilowatts of power flowing through it from a high capacity mains circuit and a wall charger full of electronics. This goes on for many hours to charge a 50 to 80 kWh battery in your car while it is completely unattended and you're asleep. A battery that is designed to put out a hundred-plus kilowatts when you stomp on the go pedal , and so is fused appropriately for that kind of current.
Of course it will also have protections, but the fact of the matter is that it's a fundamental change in the operation of your vehicle. Now instead of being "turned off" overnight, a lot of high power things are occurring. The risk of a failure is higher simply because things are actively happening. Your car is active while you're driving it just like a petrol car is, but now it's also very active while it's parked overnight.
Lots of people think they are home mechanics and like to maintain their own vehicles. Lots of business that are Mechanical workshops are either unqualified or should not be qualified.
This is not too big of a problem when all you have is 12V power, some diesel or some petrol. You may get a light electrical shock, some chemical burns if you have sensitive skin if you don’t know what you are doing. The most dangerous damage they will do to your car is suspension or brake failure while driving, or an underbonnet fuel/electrcial fire or an in-cab electrical fire. These fires can be put out with powdered fire extinguishers. If a Pb-Acid battery ruptures, you may get some nasty acid burns.
When someone who doesn’t know what they are doing, fools around with an EV, Hybrid or newer ICE car with a 48V electrical system, they can do much more damage. Damaging one of those orange cables can instantly get the coroner involved. When a cell gets ruptured in certain lithium chemistry batteries, the location of the fire will be inaccessible for days or weeks because we have no fire suppression technology that can put that bugger out.
We need to halt (or at least cut down) burning hydrocarbons for fuel, but everyone swapping their oversized ICE Sedan or SUV for an oversized EV Sedan or SUV is not the solution.