While ‘car that gets to 100km/h in less than 3 seconds is more emissive than a city scoot’ might not be a revelation to some, it’s interesting to put some hard numbers to our long-held suspicions. The boffins discovered that the Mirage emitted 192g/km for every kilometre travelled, the Tesla 226g/km and – for perhaps a fairer comparison of a potent executive express – the BMW 750i xDrive chugged out a hefty 385g/km. Well, it does have a V12 under the bonnet so perhaps that’s understandable.
The Green Vehicle Guide, which ranks all cars sold in Australia with an emissions rating, ranks the Model S at 188g/km, the Mirage at 128g/km, and the rear-drive version of the BMW 750i – the all-wheel-drive one isn’t sold here – at 242g/100km.
At this point, my maths teacher would probably want to see my workings, and these figures encompass not only the energy consumed and CO2 emitted during the cars’ driving lifetime, but also their production and end-of life recycling. The researchers also took into account the CO2 produced by the power stations necessary to generate the Model S’ electricity, in this case based in the US Midwest. In a country with greener energy generation, the Tesla would perform better. Here in Australia where coal-fired power still reigns supreme, it would doubtless emit even more carbon dioxide per kilometre.
“Both hybrids and electric vehicles are better than conventional cars in… emissions-intensive locations”, said MIT’s Jessika Trancik. This like-for-like comparison proves this but if you really want to do your bit for the environment, it’s worth asking yourself whether you really need an all-wheel-drive electric rocket ship when there’s a simpler and cheaper solution sitting in your local Mitsubishi dealer’s showroom.