Are electric vehicles “green illusions”?

New book claims EVs are worse for the environment than fossil-fuel cars

By Farah Alkhalisi on July 13, 2012 5:08 PM

It’s a longstanding debate in the automotive world: are electric cars really of any environmental benefit? University of California Berkeley academic Ozzie Zehner argues in his new book that EVs are actually less green than fossil-fuel cars once the more carbon-intensive process of their manufacturing is taken into account.

Zehner details in “Green Illusions: The Dirty Secrets of Clean Energy and The Future of Environmentalism” how batteries using rare-earth metals – which take a lot of energy to mine and process – also contribute to an EV’s environmental impact. Not that all EV batteries contain rare-earth metals (Tesla doesn’t use them, for a start, numerous more rare earth-free batteries are under development for more mainstream applications, and rare earth metals can be recycled), but anyway…

Zehner’s argument is based on a 2010 study by the American National Academy of Sciences which found fuel consumption when in use is not necessarily the largest factor in a car’s overall carbon cost. Zehner told Wired: “When you look at the whole fuel cycle — from constructing a car to disposing of it — NAS concluded that the environmental damage from electric vehicles is actually greater than that from gasoline vehicles because of manufacturing. Sixty percent of the energy input comes from the manufacturing”.

Sixty percent? Well, the NAS study is by no means the only research on EV manufacturing: check out some alternative figures.
A study by Ricardo last year for the UK’s Low Carbon Vehicle Partnership (LowCVP) found that for a typical battery EV, 46% of its total carbon footprint was generated in its production before it even hit the road. This compares to 35% for a plug-in hybrid, 31% for a hybrid and 23% for an average petrol-engine car, based on data projections for 2015-specification vehicles and predicted fuel and electricity supplies.

The study concluded that over a typical 10-year or 150,000km lifespan electrified vehicles would give an overall carbon saving – due to their lower in-use emissions – and that a typical medium-sized ICE family car would create around 24 tonnes of CO2, compared to an equivalent EV’s 18 tonnes (the lifecycle impact of a diesel was found to be roughly similar to that of a petrol-engined car).

A follow-up piece of research, presented in February 2012, assessed a popular mid-market SUV in standard, electric and range-extended EV forms, and took into account revised projections on factors including embedded emissions for battery pack production, carbon intensity of electricity and lifetime mileage. Again, a lower proportion of the ICE vehicle’s lifetime embedded carbon was in its production – 21%, compared to 35% for the EV and 29% for the RE-EV – but the EV still came out ahead overall, and crucially, the ‘payback time’ – the point at which its in-use carbon savings compensated for its higher-carbon production – was around 65,000 km, well within the predicted vehicle lifetime. And this is even before comprehensive “second life” programmes are in place for battery recycling.

You can read about this in greater detail in the July 2012 issue of Electric & Hybrid Vehicle Technology magazine (pages 68-74, available online). For some facts – and no illusions.