Buttigieg’s response: That without electric vehicle adoption, “we have very little chance of meeting our climate goals before it’s too late.”
“I take your point that the carbon profile of driving isn’t just about the tailpipe. It’s about the power that goes into the vehicle, too. And we do want to be conscious of that — although I would suggest that unlike the carbon profile of driving a diesel or gasoline vehicle, it stands only to get better each passing year as our generation sources get greener.”
Scientists say the emerging debate has an answer: EVs are not “emissions-free,” but they already produce fewer emissions over their lifetimes than gas-powered cars. While the grid must expand to accommodate more EVs on the road, forecasts indicate it likely will get more renewable in the coming years.
According to the U.S. Department of Energy, nearly 80% of electricity in the United States comes from fossil fuels. There’s no exhaust coming from electric vehicles, but the process of producing and charging them still produces carbon emissions.
However, life cycle analyses of electric vehicles — which account for all of the emissions created by producing, using and recycling them — show that EVs already produce fewer greenhouse gas emissions over the course of their lifetimes than gas-powered vehicles, and only stand to produce fewer such emissions as technology advances.
“Even if the grid is powered by coal or natural gas, an EV of the same vehicle size and capability still typically has better CO2 emissions,” said David Tuttle, a researcher at the Energy Institute at University of Texas at Austin. “So, it’s a catchy soundbite, but a false statement that conventional vehicles produce” fewer carbon emissions than their EV counterparts.
Fewer emissions overall
Scientists studying electric vehicles’ lifetime emissions have found that their carbon intensity tends to be on the front end.
Gathering the raw materials and producing EVs typically makes more greenhouse gas than gas-powered cars, according to a recent congressional analysis of the scientific literature. But gas-powered cars quickly outpace electric ones in emissions once they hit the road.
Amgad Elgowainy, senior scientist and leader of the electrification and infrastructure group at Argonne National Laboratory, and his team have spent years doing “cradle to grave” analyses. They found in 2016 that plug-in hybrids, battery electric vehicles and fuel cell electric vehicles already had lower emissions than gas- and diesel-powered vehicles and a higher capability to improve. In their newest study, which will come out later this year, that gap has only widened.
“Using the average carbon intensity to make a unit of electricity that goes into battery electric vehicles — if I compare that today to a gasoline internal combustion engine, it cuts the emissions by half,” he said.
Even if gasoline-powered engines start using the lowest-emission power source — forest residue, a renewable biomass fuel that can be treated in order to be used in conventional cars — it would still emit more greenhouse gases over its lifetime than an EV being charged with its lowest-emission power sources, solar and wind electricity.
The share of renewable energy sources making up the average U.S. grid has grown in the last five years while coal use has declined, and renewables are only expected to continue to grow, according to the U.S. Energy Information Administration. Making EV batteries lighter and more compact also decreases vehicles’ carbon footprint because it takes less energy to propel them.
“There’s no silver bullet there to see into the future. It’s all about scenarios. But in general, if you look ... at how the grid will evolve into the future, it is definitely evolving into a lower-carbon portfolio,” Elgowainy said. “The grid will become cleaner over time regardless.”
Jessika Trancik, an M.I.T. professor who runs a lab studying emerging energy technology, also told The Detroit News via email that battery electric vehicles “reliably and substantially reduce greenhouse gas emissions relative to internal combustion engine vehicles” even on today’s power grid.
For example, the Tesla Model 3 produces 87% fewer emissions over its lifetime than a comparable gas-powered car, the Mercedes-Benz A220, and the Chevrolet Bolt produces 68% fewer emissions than the comparable gas-powered Mazda 3, according to an analysis tool developed by Trancik’s lab.
That’s not to say that EVs are totally environmentally friendly: Environmental and human rights groups have raised concerns about methods used to mine the raw minerals such as cobalt and lithium needed to make electric vehicle batteries.
The majority of the world’s cobalt comes from the Democratic Republic of Congo, where many workers, including children, dig for the material by hand and are exposed to frequent safety hazards. Congolese cobalt mines can also produce hazardous waste and air pollution. Mining lithium, primarily from Australia and South America, can be particularly water-intensive — batteries can take more than 50% more water to produce than an internal combustion engine.
Expanding the grid
But Republicans note it’s not just about how EVs perform now — it’s about what will happen if a majority of cars on the road are powered by electricity rather than gasoline.
If the United States’ energy levels remain the same, it would put a strain on the grid, Department of Energy officials acknowledge.
Rep. Larry Bucshon, R-Ind., asked Energy Secretary Jennifer Granholm during a House Energy and Commerce subcommittee hearing last month how the administration plans to account for increased electricity demands due to more EVs on the road.
“There definitely will be increased demand,” the former Michigan governor said. “And that means we have to add additional energy sources to the grid. That’s why a lot of the new energy that is coming on, like solar and wind, which are cheaper than others, is an opportunity for us to continue to provide affordable electricity.”
Bucshon noted those sources will not only have to expand existing energy capabilities but will also have to replace fossil fuel energy if the administration is successful in its plans to reach carbon pollution-free electricity generation by 2035.
“It’s a big challenge,” he said.
Biden’s proposed budget includes $10 billion to support clean energy projects — which would include wind, solar, hydro and nuclear power, among others — and would increase the Department of Energy’s overall budget by more than $4 billion over the last fiscal year.
In the short term, as EVs become a larger share of cars on the road, that extra demand on the grid may or may not translate into more emissions depending on when and where the vehicles are charged, Elgowainy said. Some areas have electricity grids supported by much cleaner energy sources than others.
In the long term, meeting the administration’s clean power goals likely will require a significant expansion of wind and solar energy generation with some regional differences, according to the department. About 75% of new additions to the U.S. grid in 2020 were renewable, largely solar and wind.
“For the grid to get to 100% clean, we need to have flexible loads and storage both” to balance variability and ensure consistent energy availability, said Michael Berube, Deputy Assistant Secretary for Sustainable Transportation at the Department of Energy.
One strategy, he said, is developing regional charging strategies to take advantage of peak times when renewable sources are available. For example, supporting mid-day workplace charging in places like California, where solar can meet the extra need. Another way is to build energy storage into charging stations and buildings to meet needs at surge times.
“Transportation, our studies show, will be the largest new load to the grid, but also the most flexible. We’re very focused on thinking about smart charging technology so that you have the capability to manage when you charge those vehicles to help flatten the load.”
While the transition to electric vehicles marks a major technology shift, Berube said it’s not unprecedented — the electric grid has adapted in the past to field big new loads like air conditioning and refrigeration.
“It’s not out of the norm of what’s been done. One of our key messages is: If you wanted to do it all next year, that might be close to impossible. But if you want to do it over the next 15 years, that looks and feels a lot more like what we have done as a country over time and that’s a lot more plausible,” he said, adding that’s also why “there’s urgency. We need to get going now.”