Electric cars do not produce “exhaust” emissions, but their overall carbon footprint is not zero. The American Council on an Energy Efficient Economy (ACEEE) has argued that it is time for federal efficiency standards to reflect that.
The majority of electric vehicles use electricity from the grid, which in the United States still uses 60% of fossil fuels, the group noted last week in a blog post. The more EVs consume electricity from the dirty grid, the greater their carbon footprint. So EV efficiency is important.
For example, a Chevrolet Bolt EV is still subject to 92 grams of carbon dioxide (CO2) per mile due to the electricity used to charge it, according to ACEEE. That’s much lower than a petrol Chevy Malibu sedan, which according to analysis emits more than 320 grams per mile, but not zero.
Efficiency EV vs. weight (from ACEEE report)
However, the GMC Hummer EV causes 341 grams of CO2 per mile. That’s much better than the original Hummer H1’s 889 grams per mile, but shows that inefficient electric cars can still be more harmful to the environment than the most efficient internal combustion cars.
With current federal emissions standards based solely on fuel economy, with electric vehicles counted as zero emissions, this problem will not be solved, ACEEE argues. There is no distinction between efficient electric cars that are actually reducing overall carbon emissions and inefficient electric cars that are still contributing to the problem. So the group is calling on the EPA to find ways to include EV performance in future emissions standards.
It should also be noted that, according to some analysts, the federal fuel economy rules made US vehicles bigger. If any such rules were applied to electric vehicles, they could not have had the same effect.
EV performance versus weight without battery (from ACEEE report)
One major obstacle to increasing EV efficiency is weight. Electric vehicles are typically heavier than comparable internal combustion models because of their battery packs, and automakers want to increase the size of the kit to increase range. But even when the battery pack weight is taken into account, some electric vehicles like the Audi E-Tron S still perform poorly.
Report for 2020 considered the idea of increasing battery size versus cutting weight to increase EV range. It found that larger battery packs cost more, but the weight reduction may not be as cost-effective as it relies on more expensive materials. The report suggests that new battery technology could solve this dilemma, providing batteries with greater energy density.
In addition, some suppliers — like Magna — believe there will be large profits in just software and controls. And the idea of efficiency is core to Lucid, the first automaker to disrupt 500 miles range without the super large size battery.
