Though their market share is still marginal, electric vehicles (EVs; mainly cars) have seen an impressive growth the last few years. But how green are electric cars? Let’s compare electric cars with internal combustion engines (ICEs) during their lifetime.

To put the hype of electric cars in perspective: at the end of the 19th century, say between 1895 and 1902, over 90 percent of all New York City cabs were battery driven. Not only taxis were a common means of transport during those days, also other electric vehicles became popular due to a rapidly unfolding electricity distribution network on the US East Coast.

The rise and fall of EVs

Almost 120 years later, we’ll have a similar development, yet some aspects are quite the opposite. At the turn of the 20th century, EVs had huge advantages. Compared to ICEs they charged much faster, didn’t backfire or exhaust smoke. To put the icing on the cake, the Electric Company of William Whitney – a playboy, horse lover and former secretary of the US navy - set up a range of stations on the East Coast in which taxis could change empty batteries for charged ones.

So what caused the demise of EVs into oblivion after the 1930’s? Historians have yet to figure out whether it was the bankruptcy of Whitney (at that time seen as a system failure of electrification), Whitney’s longstanding quarrel with Henry Ford, the discovery of oil fields in Texas or the mass production of T-Fords running on ICEs. All in all, when oil prices declined rapidly and petrol stations popped up everywhere in the US, the momentum of EVs was gone and ICEs in transportation took over.

Location, location, location

By definition, electricity is not a source but a carrier of energy and, therefore, source independent. In other words, the environmental impact of EVs depends for a large part on the (road) infrastructure and how its electricity is generated. ‘Fuelled’ by coal-fired power plants – co-firing of biomass doesn’t make a difference – the impact of EVs can be on a par of ICEs or even higher.

In a way the maxim of real estate agents – ‘location is everything’ – also applies to driving electric vehicles: from an infrastructural point of view it makes a massive a difference whether you’re charging an EV in a country with a small percentage of sustainable energy sources (like Malta or the Netherlands) or in a country with a substantially higher percentage (such as Norway or Denmark).

The EU and numerous consultancies, like the Union of Concerned Scientist (UCS), have run the numbers. Roughly speaking, taking the electricity generated into consideration, EVs emit 20 to 80 percent less CO2 into the atmosphere than ICEs (an estimated 248 kilos per mile according to the EU study). Whereas China, with its huge coal power sector, accounts for 188 kilos per mile; a country like France, powered by nuclear energy, scores a mere 2.7 per mile travelled. Norway (hydro) and Denmark (wind) are on a similar path.

Battery life

That said, contrary to the turn of the 20th century at the East Coast – in which an electricity network was superior to almost non-existent petrol stations – charging EVs has lost its structural advantages nowadays. On the other hand and similar to the 1900s, experts and users do have to pay attention to distance travelled with EVs. As a rule of a thumb, the farther you travel, the heavier the battery pack – and thus your electricity consumption – has to be.

Moreover, even if you’d have a 100% sustainable electricity supplier at your home, the more you will drive, the more you’ll have to recharge your EV at fast charging fuel stations on the road (or at your office). Fast charging lowers battery life significantly while you do not have a guarantee of all your electricity bering entirely generated by wind and/or solar energy.

Up until now, the vast majority of EVs are hybrid vehicles (although full electric cars make inroads). The hybrid setup reduces energy efficiency. According to the EU study, they include all the main parts as EVs, yet they have a conventional combustion engine and associated fuel tank. In other words, their drive train is partly fuelled by gasoline or diesel. Solely driven by the ICE, a hybrid car emits more CO2 than a conventional car, due to the wieigth of its battery system.

Jack Frost

And there’s more: the faster you’ll accelerate in an EV, the quicker you have to recharge your batteries. Whereas diesel-powered ICEs can operate (almost) weather independent, the opposite is the case with EVs: not only headwinds affect the speed of the car, also the colder it gets, the worse the batteries are performing (even up to 40 percent less mileage when Jack Frost severely bites the flow of electrons, according to CBC News). Moreover, an aggressive driver consumes approximately 30 percent more electricity than an eco-aware driver, some studies claim.

To sum up: it’s a fallacy of misplaced concreteness to assume all EVs around the world are more environmentally friendly then ICEs. How green EVs really are, depends upon (road) infrastructure and sources of energy, location (country and climate), the kind of EV in use as well as the behaviour of the driver.

It’s also a fallacy of misplaced concreteness not to compare the environmental imprint of EVs with public transport. Although EVs may perform better than ICEs, train, tram, ferry and metro outpace them far and wide. Don’t say - as I’ve heard a CEO speaking in Amsterdam – that you’re so environmentally conscious by taking an electric car when it’s actually better to ride a bicycle (or hike, if you want).

Image: Electric vehicle 1904. Courtesy: Bundesarchiv, CC-BY-SA 3.0