- Driving on electricity produces far fewer emissions than gasoline
- How efficient would an ICE vehicle need to be to have the same global warming emissions as an EV?
- Electrifying larger vehicles like pickups also have significant benefits
- EVs are responsible for less than half the global warming pollution of gasoline cars, even when including emissions from manufacturing
- EV efficiency and recycling are important to reduce impacts of battery manufacturing
- Cleaner vehicles AND cleaner electricity are the solution to slowing climate change
GMC HUMMER EV models take center stage at the 2021 SEMA Show. Source: GMC
Transportation is the largest source of global warming emissions in the US and the passenger cars, trucks, and SUVs produce the majority of transportation emissions. Limiting climate change will require the rapid reduction in these emissions from the vehicles we drive.
Electric vehicles (EVs) can eliminate tailpipe emissions altogether and so are an attractive option for reducing both global-warming and smog-forming air pollution.
While EVs can have no tailpipe emissions, there are emissions from electricity generation. There are also emissions from extracting the materials and the manufacturing processes required to make EVs. Since the goal is to reduce emissions, a natural question is: what are the net benefits of switching from gasoline-powered cars and trucks to fully-electric vehicles?
To answer that question, I and my colleagues in the Clean Transportation program have analyzed the global warming emissions from all of the steps required to make and recharge EVs and compared that to the emissions from making and driving a comparable gasoline vehicle.
Driving on electricity produces far fewer emissions than gasoline
To compare driving on electricity versus gasoline, we need to consider all of the global warming emissions that occur in producing and using those fuels. For an EV that means:
- Emissions that result from raw-material extraction, such as coal mining and natural gas drilling;
- Emissions from delivering these fuels to power plants;
- Emissions from burning those fuels in power plants to generate electricity;
- Electricity losses that occur during distribution from power plants to the point where the electric vehicle is plugged in; and
- The efficiency of the vehicle in using electricity.
Similarly, our assessment of the global warming emissions from comparable gasoline and diesel vehicles addresses emissions that result from:
- Oil extraction at the well;
- Transporting crude oil to a refinery;
- Refining oil into gasoline;
- Delivering fuel to gas stations; and
- Combusting fuel in the vehicle’s engine.
Because of differences in electricity generation across the United States, the emissions produced from driving the average EV vary depending on where the vehicle is driven but everywhere in the United States, driving the average EV results in lower emissions than the average new gasoline vehicle.
How efficient would an ICE vehicle need to be to have the same global warming emissions as an EV?
To make it easier to compare EV driving emissions to gasoline vehicles, we’ve converted the emissions into a gasoline miles-per-gallon equivalent—an MPGghg, where ghg stands for greenhouse gas (i.e., global warming) emissions.
If an EV has an MPGghg value equal to the miles per gallon of a gasoline-powered vehicle, both vehicles would produce the same amount of global warming pollution for each mile traveled. If the MPGghg of an EV is twice that of a gasoline vehicle mpg, the emissions from driving the EV would be half those produced from driving the gasoline vehicle.
Over 90 percent of people in the United State live where driving the average EV produces fewer global warming emissions than the most efficient gasoline vehicle (59 mpg). Based on where EVs have been sold in the United States, driving on electricity produces emissions equal to those of a gasoline car getting 91 miles per gallon. Note: Acronyms refer to electricity grid regions as defined by EPA’s eGRID database.
While driving the average EV yields significant emissions savings, the more efficient the EV, the greater the benefits of switching from gasoline to electricity. Driving the most efficient EV produces lower emissions than the most efficient gasoline car where 97 percent of the population lives—in other words, virtually everywhere in the United States.
For example, the emissions from driving a 2021 Tesla Model 3 Standard Range Plus in California equal those of a gasoline car getting 152 miles per gallon.
The Tesla’s global warming emissions are a fifth of those of the average new gasoline car and over 60 percent less than even the most efficient gasoline car on the market. If you want to explore the emissions from other models in different regions of the country, you can use our EV emission tool.
A Ford F-150 Lightning at Ford’s Rouge Electric Vehicle Center in Dearborn, Michigan.
Electrifying larger vehicles like pickups also have significant benefits
Larger EVs, like SUVs and pickup trucks (known as utes in Australia) are becoming available, including an electric version of the Ford F-150 pickup truck, the highest volume vehicle sold in the US. Larger vehicles, whether gasoline or electric-powered, are less efficient.
However, switching from gasoline to electricity still has an advantage. Everywhere in the United States, the emissions from driving an EV pickup truck are lower than those for the average new gasoline or diesel pickup truck.
Driving an electric pickup truck produces lower emissions than the most efficient gasoline model in most of the United States. For example, recharging and driving the Rivian R1T or Ford F-150 Lightning pickup in California has the emissions impact of a hypothetical 76 mpg gasoline truck. Overall, based on where EVs have been sold, EV pickups on average would have emissions equal to a 59 mpg gasoline truck.
EVs are responsible for less than half the global warming pollution of gasoline cars, even when including emissions from manufacturing
Manufacturing an EV results in more global warming emissions than manufacturing a comparable gasoline vehicle.
This is chiefly due to the energy and materials required to produce an EV’s battery. However, most of the global warming emissions over the lifespan of today’s vehicles occur during use, so the reductions from driving an EV more than offset the higher manufacturing emissions.
When comparing the average gasoline sedan (32 mpg) to the average-efficiency EV car with a 300-mile-range battery, the EV reduces total lifetime emissions 52 percent. An EV pickup truck reduces lifetime emissions 57 percent compared with the average gasoline pickup.
Another way to understand how emissions savings from driving an EV offset additional manufacturing emissions is to consider the breakeven point: how far (or how long) an EV needs to drive for the savings to match the initial emissions “debt.”
This breakeven point varies depending on regional electricity emissions. Based on where the US population lives, the mean breakeven point for an electric car with a 300-mile range compared with the average new gasoline sedan is 21,300 miles of driving, or 22 months based on average annual driving.
Breakeven occurs more quickly, after about 17,500 miles (17 months), when comparing an electric truck with 300-mile range with the average new gasoline pickup truck.
EV efficiency and recycling are important to reduce impacts of battery manufacturing
Both EV cars and trucks are much cleaner than their gasoline counterparts, but electric trucks are responsible for more global warming emissions than electric cars simply because trucks are larger and heavier. Choosing the most efficient EV that meets mobility needs will minimize overall pollution. If a sedan meets a driver’s needs, that would be a better choice for the environment than a full-size SUV or a pickup.
In addition to lower emissions while driving, more efficient EVs can use a smaller capacity battery to achieve the same driving range. Reducing the size of the battery will lower the global warming emissions from materials and manufacturing.
Also, the impacts of manufacturing EVs, including their batteries, extend beyond global warming emissions. Manufacturing processes and the sourcing of battery and other materials also affect water and air quality.
Processes and sourcing can raise concerns over human rights and the ethical issues involved in mining and refining raw materials. This makes it essential to reduce the use of raw materials needed to make EVs.
Using smaller batteries in more efficient vehicles will help. The reuse, remanufacturing, and recovery of materials from used batteries are also important to reduce the negative impacts.
Cleaner vehicles AND cleaner electricity are the solution to slowing climate change
Switching from conventional vehicles to electric vehicles reduces carbon emissions and smog-forming air pollution. To maximize these reductions, we must accelerate the adoption of EVs and transition to renewable electricity as quickly as possible.
These dual transitions are a necessary part of putting the United States on a trajectory toward net-zero climate emissions by midcentury.
This article was first published by the Union of Concerned Scientists. David Reichmuth is senior engineer for its Clean Transportation Program.
Keyword: Electrifying utes and SUVs offers big benefits, research shows