Looking at electric vehicles in combination with some renewable energy source, you might properly come to the conclusion that they are cleaner than conventional vehicles.
Electric vehicle use emissions are most definitely cleaner, but what happens when you consider lifecycle emissions? For example, aside from the power supply that is used to charge the lithium-ion battery pack, what about the emissions generated manufacturing the battery pack itself?
A recent study completed by Renault, a French automaker, recently completed a study that compares the lifecycle emissions of three vehicles in the Renault Fluence lineup. The conventional vehicles, the diesel version, powered by a 1.5ℓ i4 engine, and the gasoline version, powered by a 1.6ℓ i4, were compared to the ZE electric vehicle, with a 22kWh lithium-ion battery pack and 70kW electric motor.
A number of lifecycle emissions factors were included in the Renault study, including links to energy sources, water and air pollution, and carbon dioxide emissions, among others, at four different stages in the lifecycle, from production to recycling. The lithium-ion battery pack and electric motor did push up emissions for a couple of factors, but overall, the ZE electric vehicle has lower lifecycle emissions than the diesel and gasoline conventional vehicles. [See Image for Comparison.]
What’s the deciding factor? Lifecycle emissions pretty much boil down to what fuel you use. Diesel fuel ends up being cleaner than gasoline, mainly because diesel engines are inherently more efficient, but are still worse for the environment than electric vehicles.
Some may point to dirty power plants pushing emissions higher when recharging, but a Stanford University study points out that even powered by coal, electric vehicles are cleaner. Since the 2006 Study, coal power has actually dropped, meaning electric vehicles are actually getting cleaner as the power grid gets cleaner.
Image © Renault