About this series: As a BTG supporter, you understand that our transportation choices have tremendous ecological impacts, but you may not be aware of the latest innovations and improvements in your options. With this series, we hope to help you find new ways to both lower your individual impact now and move us all toward a sustainable transportation system ASAP. Please send us any additional suggestions you have.
In Part 1, we looked at options for getting around without a car at least some of the time as well as how some of us may even be able to avoid owning a car entirely.
In Part 2, we looked at how to drive greener when you do and what to consider when trying to decide whether to keep your current car or buy a new one.
In Part 3, we considered the impacts of driving a plug-in car.
In Part 4, we explored some of the obstacles to electrifying our car culture.
In Part 5, we delved deeper into the benefits of driving the right-size car.
Now, in Part 6, we explore the implications of the latest data comparing the global warming impacts of electric cars to gasoline-powered cars by regional electric grid.
Since we published Part 3 of this series in April – which concluded that high-MPG hybrids, not electric cars, were still the best choice for the climate in metro-KC because our regional grid is still so heavily-dependent on coal-fired power plants – the landscape has changed.
That post was primarily based on a study by the Union of Concerned Scientists (UCS) titled “Cleaner Cars from Cradle to Grave: How Electric Cars Beat Gasoline Cars on Lifetime Global Warming Emissions.” It was originally published in November 2015 and relied on 2012 data from the EPA. The authors concluded that an electric car with then-average efficiency would produce emissions equivalent to a gasoline-powered vehicle averaging 35 MPG Combined City/Highway when charged from our grid. As we noted, there were 16 hybrid models on the market then that were rated to do better than that.
At the end of May, however, UCS updated the study using the EPA’s data on emissions from electricity generation through the end of 2014. Improvements to the regional generation mix and other changes now mean that an electric car with average efficiency charged from our regional grid would produce emissions equivalent to a gasoline-powered car getting 46 MPG Combined.
That jump of 11 MPG means a huge increase in the benefits of switching to an electric car in KC. There are only four hybrid models on the market rated to do better than 46 MPG Combined:
- Honda Accord Hybrid 48 MPG
- Hyundai Ioniq 55 or 58 (Blue version)
- Kia Niro 49 or 50 (FE version)
- Toyota Prius 52 or 56 (Eco version)
While this means an electric car still won’t be the lowest-emission option (unless you can charge from clean energy), it does mean that an electric car may well be the best choice once other factors are taken into account.
First, electric cars produce no tailpipe pollution, so they do even more than hybrids to keep the air clean.
Second, electric cars have far fewer parts to maintain and replace.
Third, oil spills and pollutes the water and land in ways even dirty old coal does not.
Fourth, the grid should keep getting cleaner over time, whereas the oil industry is turning to ever-dirtier and riskier sources of oil like deepwater drilling, tar sands, and tight oil (which is extracted using hydraulic fracturing, or fracking) as we burn through the world’s finite oil reserves.
Fifth, we are social animals, and the social signal sent by choosing to drive an electric car today is much more potent than driving a hybrid car. Hybrids have become pretty common and unremarkable over the 17 years since the first model went on-sale in the US, but electric cars are still quite distinctive. Our ability to meet the challenge of the climate change emergency while there’s still time depends most fundamentally on social change.
A caveat, though: The UCS calculations we’re relying on here are based on an electric car with average efficiency. Electric cars vary tremendously in their EPA ratings, from a low of 86 Combined Miles per gallon equivalent (MPGe) for the Tesla Model X P100D crossover to a high of 136 MPGe for the new Hyundai Ioniq Electric.
What explains these differences in MPGe ratings? Some models are certainly much less aerodynamic than others (though the Model X and Ioniq actually have the same drag coefficient, 0.24), but the primary factor is weight:
The Model X P100D has a curb weight of 5,531 lbs.(!) whereas the heaviest Ioniq Electric, the Limited trim, weighs 3,285 lbs. It takes a lot of energy to haul around another 2,246 lbs.
Fortunately, UCS has created a tool that allows you to enter your Zip Code and the electric car model you’re considering to find out how its emissions would compare to a gasoline-powered car where you live.
As an aside, it’s striking how quickly the global warming pollution produced by driving an electric car in KC has decreased. As recently as August 2012, UCS was projecting that an electric car with the efficiency of the 2011 Nissan LEAF would still be producing emissions equivalent to a 39 MPG gasoline-powered car in 2025.
All of us who have been working hard for policies to reduce emissions and promote clean energy deserve to be proud.