How much electricity would it take to power all cars if they were electric?

In 2022, California became the first state to require all new cars and light trucks sold to be zero emission vehicles by 2035. Because several states have laws or rules on the books agreeing to follow California’s vehicle emission standards, about 34% of states in the US are expected to follow suit.^[1]

While electric vehicles (EVs) currently represent a modest proportion of the automotive market, sales of all types of EVs are expected to continue growing in the near-future.

This raises questions over how much more electricity would be needed to power these cars, and how much more cost-effective EVs are per mile.

Based on 2019 data, the US would need to produce 20-50% more electricity in a year if all cars were EVs.

According to data from the Department of Energy (DOE), the cost of powering EVs is approximately 35-75% cheaper than the cost for gas-powered vehicles per mile.

Since generating electricity often relies on the use of fossil fuels, switching to EVs won’t eliminate vehicle-related emissions of greenhouse gases. The emission rates for EVs would vary by state based on how electricity is generated.

How much electricity would it take to power all cars if they were EVs?

In 2019, drivers across the US consumed roughly 3.4 billion barrels, or 142.8 billion gallons, of motor gasoline.

According to the EPA, every gallon of gasoline is equivalent to 33.7 kilowatt-hours (kWh) of electricity. Based on these metrics, an equivalent of approximately 4,800 billion kWh was used to fuel gasoline vehicles over that year.

According to the Office of Energy Efficiency and Renewable Energy, EVs are roughly two and a half to six times more efficient using energy from the power grid than conventional cars are using gasoline. Given that comparison, it would take roughly 800 to 1,900 billion kWh of electricity to power all vehicles if they were EVs.

The US used about 4,130 billion kWh of electricity in 2019. This means if all cars were EVs that year, the US would have consumed 20-50% more electricity.

This estimate doesn’t account for the number of charging stations or the differences in energy efficiency across all EVs.

How does the fuel economy of EVs compare to regular gas-powered vehicles?

Compared to fuel economy rates for all gasoline-powered vehicles in 2021, fueling costs for EVs were anywhere between 35% to 75% cheaper than vehicles which used retail motor gasoline, on average.

The annual fuel cost for all EVs on the market ranges from $500 to $1,850 per year, according to DOE data. Using the assumed fuel economy benchmarks set in those estimates^[2], this translates to a cost range of $0.03 to $0.12 per mile travelled in an EV.

Furthermore, a 2021 study by the DOE comparing the costs of driving gas-powered cars to EVs found that the average fuel cost savings for an EV driver was about 60%. This range varied by state depending on the local electricity and gasoline prices.

While miles per gallon for conventional vehicles continues to improve over time, EVs remain more efficient, even after considering those advances.

According to the EPA’s Automotive Trends Report, the most fuel-efficient vehicles since 2011 have all been EVs.

Based on these factors, the cost of traveling a mile in EVs has fallen from roughly $0.09 to $0.12 in the late 1990s to $0.06 or less per mile today for 90% of EVs sold in the last decade.

In addition to fuel efficiency, the cost of different energy sources for fuel may be more volatile, making it more difficult to predict the cost of travel over time.

While the price for retail electricity has remained relatively stable over the past decade, gas prices are more volatile.

Since 2011, the average nationwide cost of retail gasoline has increased by 46%, while the cost of residential electricity has increased by 30%.^[3]

Switching all cars to EVs would have a number of difficult-to-predict effects that aren’t guessed at in this analysis. For example, electricity prices could become more volatile if cars relied on the power grid instead of gasoline for fuel.

Where does electricity for the power grid currently come from?

In 2021, more than 60% of the nation’s electricity was generated by fossil fuels. While this ratio has fallen since 2010, when the total was 70%, it means powering EVs can still produce emissions.

But how electricity is produced differs greatly between states. And those differences impact total emissions produced when powering EVs.

According to the Alternative Fuels Data Center, all-electric vehicles produced an annual average of 2,817 pounds of CO2 equivalent emissions per vehicle across the country in 2021, compared to 12,594 pounds of CO2 equivalent emissions per gas-powered vehicle the same year.

In West Virginia, annual emissions per EVs in the state was 6,228 pounds of CO2 equivalent emissions in 2021. That’s nearly triple the annual emissions than in neighboring Virginia at 2,085 pounds of CO2 equivalent emissions. This is largely due to West Virginia relying on coal for over 90% of its electric power compared to Virginia, which relies on a more diverse energy portfolio, including natural gas and nuclear power.

Learn more about US energy, including emissions produced by electric cars or the number of EV charging stations in the US today, and get data directly in your inbox by signing up for our newsletter.