Death rates in hybrids ‘three times higher’ than petrol cars, data shows

UK newspapers have reported, citing official data, that motorists in hybrid cars are three times more likely to die than those in petrol cars.

Analysing figures from the Department of Transport, the newspapers said 122 people died in collisions involving hybrid vehicles and 777 in petrol car crashes last year.

With petrol models outnumbering hybrid vehicles by almost 20 to one on UK roads, this suggests that hybrids are involved in approximately three times as many fatal crashes, reported The Times.

It reported that the data was obtained by The Mail on Sunday.

Overall, the data shows that there was one death for every 8,000 hybrid cars on the roads last year compared with one death for every 20,000 diesel vehicles and one death for every 25,000 petrol engines, according to The Times.

Fully electric vehicles have the lowest fatality rate at one death for every 55,000 of the cars on the road.

The Mail reported that road safety experts were calling for an enquiry into the trend.

Hybrid cars pair internal combustion engines with electric motors and high-voltage battery systems. People like hybrids because they combine the convenience and cost savings of electric charging with the reliability and long range of petrol or diesel engines.

The combination of petrol engines and batteries and electric motors, can be harder to control and more prone to fires, The Mail reported.

The cars' batteries may also be to blame, said The Mail report, adding batteries can be damaged by the heat of the engine, which burns at extremely hot temperatures.

The high electric current running through the car also increases the risks for passengers involved in crashes, reported The Mail.

First responders need special training and equipment due to the different nature of hybrid fires, and the potential for toxic gas to be released, said The Mail.

The Telegraph, citing experts, called hybrid engines more complex than petrol or diesel-fuelled cars.

Last year the Swedish Civil Contingencies Agency found that hybrid vehicles face the highest fire risk, with 3,475 conflagrations per 100,000 vehicles.

This was compared with 1,530 fires per 100,000 for petrol or diesel cars and 25 per 100,000 for electric vehicles.

The Telegraph quoted the Department for Transport guidance as saying, “Battery fire may result in jet-like, directional flames and will release toxic chemicals, which can pose a risk to health.

A normal vehicle fire, however, could develop quickly into a main battery fire if left long enough; hence, in the event of an EV fire, defer to the fire service.”

Nicholas Lyes, of the road safety charity IAM RoadSmart, told The Times that with “two power sources, two cooling systems and more complicated electronics and wiring”, hybrids could create “complex fire scenarios which are harder for firemen to put out”.

Citing experts, The Times said several factors are present in hybrid cars to cause the disproportionate fatality rate seen in hybrids.

The additional weight of batteries and electric motors alters vehicle dynamics and crashes energy distribution compared with single-engine cars, The Telegraph reported.

Batteries situated under the vehicle floor, for example, have different crush behaviour in high-impact scenarios, the report said.

And while internal combustion engines can ignite petrol in crashes, lithium-ion battery thermal events, though infrequent, burn hotter and with chemical complexity, the report added.

Some experts blame the number of miles that hybrids can clock up, with many taxi drivers using them due to their fuel efficiency. But as they age, the risks posed by the cars grow as the batteries wear down and performance wanes, The Mail reported.

The concern over fires is not confined to crashes.

The Ford Kuga plug-in hybrid, one of the UK’s more popular electrified vehicles, has been the subject of multiple battery-related fire risk recalls, The Times reported.