Transportation is the largest source of global warming emissions in the United States, and passenger cars, trucks, and SUVs produce the majority of transportation emissions. Limiting climate change will require the rapid reduction of these emissions from the vehicles we drive. Electric vehicles (EVs) can completely eliminate tailpipe emissions and are therefore an attractive option for reducing both global warming and smog-causing air pollution.
While electric vehicles may have zero tailpipe emissions, there are emissions from power generation. There are also emissions from the extraction of materials and manufacturing processes needed to manufacture electric vehicles. Given that the goal is to reduce emissions, a natural question is: what are the net benefits of switching from gas-powered cars and trucks to fully electric vehicles? To answer this question, my colleagues in the Clean Transportation program and I analyzed global warming emissions from all the steps required to manufacture and charge electric vehicles and compared them to emissions from manufacturing and driving a comparable gasoline-powered 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 during the production and use of these fuels. For a VE this means:
- Emissions resulting from the extraction of raw materials, such as coal mining and natural gas drilling;
- Emissions from the delivery of these fuels to power plants;
- Emissions from the combustion of these fuels in power plants to generate electricity;
- Electricity losses that occur during distribution from power stations to the point where the electric vehicle is plugged in; and
- The vehicle’s efficiency in using electricity.
Similarly, our assessment of global warming emissions from comparable gasoline and diesel vehicles covers emissions resulting from:
- Extraction of oil at the well;
- Transportation of crude oil to a refinery;
- refining oil into gasoline;
- Delivery of fuel to service stations; and
- Burning fuel in vehicle engine.
Due to differences in electricity production in the United States, the emissions produced by driving the average electric vehicle vary depending on where the vehicle is driven, but everywhere in the United States driving the medium Electric vehicles generate fewer emissions than medium new gasoline vehicle.
How efficient would a gas-powered vehicle have to be to have the same global warming emissions as an electric vehicle?
To make it easier to compare the emissions of electric vehicles and gasoline vehicles, we have converted the emissions to a gasoline equivalent in miles per gallon, an MPGghg, where ghg stands for greenhouse gas emissions (i.e. global warming). If an EV has an MPGghg equal to the miles per gallon of a gasoline-powered vehicle, both vehicles would produce the same amount of global warming pollution for every mile driven. If the MPGghg of an electric vehicle is twice that of a gasoline vehicle mpg, the emissions from driving the electric vehicle would be half of those produced by driving the gasoline vehicle.
While driving an average electric vehicle provides significant emissions savings, the more efficient the electric vehicle, the greater the benefits of switching from gasoline to electric. Drive the the most efficient EV produces fewer emissions than the the most efficient gasoline-powered car where 97% of the population lives, that is, virtually everywhere in the United States. For example, the emissions from driving a 2021 Tesla Model 3 Standard Range Plus in California are equal to those of a gas-powered car consuming 152 miles per gallon. The Tesla’s global warming emissions are one-fifth of those of an average new gas-powered car and more than 60% less than the most efficient gas-powered car on the market. If you want to explore the emissions of other models in different parts of the country, you can use our EV emissions tool.
Electrifying larger vehicles like vans also has significant benefits
Larger electric vehicles, such as SUVs and pickup trucks, are becoming available, including an electric version of the Ford F-150 pickup truck, the top-selling vehicle in the United States. Large vehicles, whether gasoline or electric, are less efficient. However, switching from gasoline to electric still has an advantage. Across the United States, emissions from driving an electric pickup truck are lower than those from an average new gasoline or diesel pickup truck.
Electric vehicles are responsible for less than half of the global warming pollution of gas-powered cars, even including manufacturing emissions
Manufacturing an electric vehicle results in more global warming emissions than manufacturing a comparable gasoline-powered vehicle. This is mainly due to the energy and materials required to produce an EV battery. However, most global warming emissions over the lifetime of today’s vehicles occur during use, so the reductions resulting from driving an EV more than offset the emissions from manufacturing more. high. When comparing the average gas sedan (32 mpg) to the average efficiency EV car with a 300 mile battery range, the EV reduces total lifetime emissions by 52%. An electric van reduces lifetime emissions by 57% compared to an average gasoline-powered van.
Another way to understand how the emissions savings from driving an EV offset the additional manufacturing emissions is to consider the break-even point: how far (or how long) an EV has to travel for the savings correspond to the initial emissions “debt”. This break-even point varies according to regional electricity emissions. Depending on where the American population lives, the average break-even point for an electric car with a range of 300 miles versus the average new gasoline sedan is 21,300 miles of driving, or 22 months based on average annual driving. Break-even occurs faster, after about 17,500 miles (17 months), when comparing a 300-mile range electric truck with the new average gas-powered pickup truck.
Electric vehicle efficiency and recycling are important to reduce the impacts of battery manufacturing
Electric cars and trucks are much cleaner than their gas-powered counterparts, but electric trucks are responsible for more global warming emissions than electric cars simply because the trucks are bigger and heavier. Choosing the most efficient electric vehicle that meets mobility needs will minimize overall pollution. If a sedan meets a driver’s needs, it would be a better choice for the environment than a full-size SUV or pickup truck.
In addition to reducing emissions while driving, more efficient electric vehicles can use a smaller capacity battery to achieve the same range. Reducing battery size will reduce global warming emissions from materials and manufacturing. Moreover, the impacts of manufacturing electric vehicles, including their batteries, go beyond global warming emissions. Manufacturing processes and the sourcing of batteries and other materials also affect water and air quality. Processes and sourcing can raise concerns about human rights and ethical issues related to the extraction and refining of raw materials. It is therefore essential to reduce the use of the raw materials needed to manufacture electric vehicles. Using smaller batteries in more efficient vehicles will help. Reusing, refurbishing and recovering materials from used batteries is also important to reduce negative impacts.
Cleaner vehicles AND cleaner electricity are the key to slowing climate change
Switching from conventional to electric vehicles reduces carbon emissions and smog-forming air pollution. To maximize these reductions, we need to accelerate the adoption of electric vehicles and the transition to renewable electricity as quickly as possible. These dual transitions are necessary to put the United States on a path to net-zero climate emissions by mid-century.
Editor’s Note (7/25): Edited a subtitle for clarity.