Car travel is on the rise in the US, and so are greenhouse gas emissions from the transportation sector.
Vehicle miles traveled by light-duty vehicles — which include passenger cars and light-duty trucks — increased 46.1% between 1990 and 2018. And in 2018, the transportation sector was responsible for 28.2% of all US greenhouse gas emissions — the largest share of any sector — with light-duty vehicles generating over half of the emissions in this sector.
Meanwhile, both President Donald Trump and former Vice President Joe Biden expressed enthusiasm for electric vehicles at the first presidential debate. Biden relayed his plan to electrify the federal fleet and deploy charging stations at scale, while Trump said he would be “all for electric cars with big incentives.”
To put those proposals in context, here is a data-driven look at electric vehicle adoption in the US.
There are three categories of electric-drive vehicles: Hybrid electric, plug-in hybrid electric, and all-electric.
The Department of Energy (DOE) defines electric-drive vehicles as those that “use electricity as their primary power source or to improve the efficiency of conventional vehicle designs.” Within this definition, electric-drive vehicles fall into three main categories, as defined by the DOE:
Hybrid electric vehicles (HEVs) are powered by a traditional gasoline or diesel internal combustion system (ICE) and by an electric motor that uses energy stored in a battery. The battery is charged by the ICE and through regenerative braking. The electric motor provides extra power during starts and acceleration, allowing for a smaller engine. This results in better fuel economy without sacrificing performance.
Plug-in hybrid electric vehicles (PHEVs) are similar to HEVs but have a larger battery that allows it to travel on electricity alone. The battery can be charged by plugging into an electric power source, through regenerative braking, and by the ICE. They can be fueled solely with gasoline, like a conventional HEV. However, they will not achieve maximum fuel economy or take full advantage of their all-electric capabilities without plugging in.
All-electric vehicles (EVs) run on electricity alone. They are powered by an electric motor that uses energy stored in a battery (larger than the batteries in an HEV or PHEV). EV batteries are charged by plugging the vehicle into an electric power source and (to a lesser degree) through regenerative braking.
The term “electric vehicle” is sometimes used to describe all-electric vehicles exclusively, although it can also be used to refer to both plug-in hybrids and all-electric cars since both can be operated using electricity alone. A more specific term for this combination is “plug-in electric vehicle.” Cars in this combined category may qualify for a federal tax credit of up to $7,500, depending on the vehicle make and model.
With these groupings in mind, here is the most recent data on electric vehicle adoption in the US, drawn from the DOE's Alternative Fuels Data Center.
Collectively, about 727,000 electric-drive vehicles were sold in 2019 — and just under half of those were plug-in electric cars capable of operating on electricity alone. For comparison, a total of 17 million new light-duty vehicles were sold in 2019 according to the Bureau of Transportation Statistics.
Hybrid electric vehicles have been on the market longer than plug-in electrics and almost 5.4 million have sold, but sales peaked in 2013.
The Honda Insight was the first hybrid electric vehicle available, coming on the market in 1999 with just 17 sales. Hybrid electric sales peaked in 2013 when almost 500,000 vehicles sold, accounting for 3.2% of the light-duty vehicle market in that year. Sales dipped in recent years, and the 400,000 sold in 2019 accounted for just 2.3% of new light-duty vehicle sales.
Of the 32 hybrid electric models available in 2019, the Toyota RAV4, Ford Fusion, and Toyota Prius were the most popular. Each had between 47,000 and 92,000 sales — or between 12% and 23% of all hybrid electric sales.
Just under 5.4 million hybrid electric cars have sold in the United States as of 2019 — comprising 1.6% of all 333 million new light-duty vehicle sales between 1999 and 2019.
Plug-in electric cars came on the market in 2010, and over 1.4 million have sold since.
When the first plug-in electric vehicle hit the market in 2010, just 300 were sold. All were plug-in hybrids since all-electric cars had yet to enter the market. All-electric cars came on the scene the following year with just over 10,000 sales — alongside 7,700 plug-in hybrid sales — bringing total plug-in electric vehicle sales to 17,700, or one-tenth of one percent of all new light-duty vehicle sales in 2011.
By 2019, plug-in electric sales climbed to 327,000, making up almost 2% of new light-duty vehicle sales that year. In contrast to earlier years when all-electric and plug-in hybrid sales were somewhat evenly matched, almost three-quarters of all plug-in electric vehicle sales in 2019 were all-electric models.
Forty-five models were sold in 2019, but the all-electric Tesla Model 3 was the most popular by far, with over 154,000 vehicles sold — or 47% of total plug-in electric sales. The Toyota Prius plug-in hybrid was next, capturing 7% of plug-in electric sales.
Just over 1.4 million plug-in electric cars have sold in the United States as of 2019 — with about 60% of those sales in all-electric cars and 40% in plug-in hybrids. Plug-in electric cars accounted for just under 1% of all 146 million new light-duty vehicle sales between 2011 and 2019.
In 2018, almost half of the nation’s all-electric registrations were in California.
While data on electric-drive vehicle sales is available only at the national level, the DOE publishes state-level registration counts for all-electric vehicles. Hybrid vehicles of both varieties, plug-in and non-plug-in, are excluded from these counts.
In 2018, states reported a total of 543,610 all-electric vehicle registrations. California accounted for 256,800 of those — or 47% of the nation’s total. Just 10 states accounted for over three-quarters of the nation’s all-electric vehicle registrations in 2018.
Adjusted for state population sizes, California still led in 2018 with over 650 all-electric registrations per 100,000 residents, followed by Hawaii at 464, Washington state at 378, and Oregon at 297 registrations per 100,000. Another 11 states plus Washington, DC recorded over 100 all-electric vehicle registrations per 100,000, while 35 states had fewer than 100 all-electric cars per 100,000 residents in 2018.
The shift toward electric-drive vehicles and other alternative fuel types has contributed to improvements in average fuel efficiency over the past several decades.
Average fuel efficiency across all car types increased from about 20 miles per gallon in 1984 to 26 miles per gallon in 2019. Most of this increase happened over the past decade, coinciding with increased fuel economy standards that went into effect in 2012.
In March 2020, the National Highway Traffic Safety Administration and the Environmental Protection Agency jointly released a rule to reduce fuel economy standards for cars in model years 2021 through 2026. The Safer Affordable Fuel Efficient (SAFE) vehicles rule will require automakers to improve fuel efficiency by 1.5% per year and reach an average of 40.4 miles per gallon by 2026, a reduction from previous standards — finalized in 2012 — which would have required 5% annual increase in fuel efficiency, reaching an average of 54.5 miles per gallon by 2025.
California’s attorney general — leading a coalition of 24 attorneys general — filed a lawsuit in response to the SAFE rule, claiming that the new rule will halt progress on fuel economy improvements and emissions reductions.