Hybrid vs Electric Cars: Which Is Greener?

Car charging at electric vehicle station
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Plug-in hybrid electric vehicles (PHEV) rose in popularity for their convenience and supposed eco-friendly profile. However, in most instances, a plug-in hybrid is less environmentally friendly than an electric vehicle (EV). In many instances, hybrids are even worse than the gasoline-powered vehicles they were meant to replace.

In the coming years, there will be less incentive to buy PHEVs for either convenience or price.

Fueling vs Charging

One of the main reasons people choose plug-in hybrids over EVs is the fact that hybrids usually have a greater range. Potential buyers want to reduce their carbon footprint, but they also want the convenience of being able to easily refuel their vehicle on a road trip.

Charging infrastructure for electric vehicles can be spotty. While Tesla has installed a network of over 1,000 Supercharger locations in the United States and over 25,000 stations worldwide, they are only available to Tesla vehicles.

However, charger coverage is rapidly improving. Tesla plans to open up its network to other vehicles. The U.S. government has plans to rapidly install an EV charging network of 500,000 charging stations.

With political will, EV chargers can be installed quickly. In the month of December 2020, China installed 112,000 EV charging stations, more than existed in the entire United States at the time.

Two vehicles at charging stations

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Environmental Impact

Over the entire life cycle of a vehicle, from raw materials to final disposal, driving an EV produces fewer pollutants and less greenhouse gas emissions than a comparable hybrid vehicle.

Only in a few regions around the world where the vast majority of electricity is generated by coal do hybrids produce fewer lifetime emissions than EVs. This exception applies to no more than 5% of the world's transport.

A 2020 study from the International Council on Clean Transportation (ICCT) found that the majority of miles driven in a PHEV are “extra-urban driving,” where the gasoline engine is used. Moreover, the same study found that PHEV owners do not charge their vehicles often enough to take advantage of their greater fuel efficiency. As a result, in real-world driving, PHEVs' electric motors are used for only half the expected amount of time. Their CO2 emissions are thus two to four times higher than regulations allow.

A separate 2020 study from Transport & Environment found that because PHEVs are heavier than gasoline cars, they consume more fuel.

This poses a dilemma for potential plug-in hybrid buyers. They want to reduce their carbon footprint while retaining the ability to drive longer distances than an EV allows on a single charge. But it's precisely long-distance driving that reduces the environmental benefits of PHEVs.

Financial Considerations

Many "green" options cost more than unsustainable counterparts, so buyers have to weigh financial concerns and environmental ones.

Depending on the use case, a plug-in hybrid can be cheaper than an electric vehicle, or vice versa. That is likely to change in the future since the current reasons for preferring a PHEV are areas where EVs are improving the fastest.

The engine and electric motor of a hybrid vehicle
Two means of propulsion means more maintenance.

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According to a 2021 study from the U.S. Department of Energy's Argonne National Laboratory, maintenance costs of an electric vehicle are lower than a plug-in hybrid: $0.061 per mile for an EV versus $0.090 for a PHEV.

The study also determined that an EV had a better average fuel economy than a PHEV: the equivalent of 91.9 miles per gallon for an EV compared to 62.96 mpg for a PHEV.

Yet because of the higher purchasing cost of EVs, due largely to the price of their batteries, the study concluded that PHEVs on average have a lower total cost of ownership than electric vehicles.

But driving habits influence this comparison in the real world. According to the EPA's Fuel Economy Guide Model Year 2021, the average annual estimated fuel cost of a 2021-model EV was $667.50, while that of a PHEV was $1,481.73.These costs for PHEVs may be under-estimated since PHEVs run on gasoline at overestimated rates.

Electricity is also far cheaper than gasoline. In March 2021, the average price of a gallon of gasoline was $2.85, while the price of an equivalent amount of electricity was $1.16. And as the ICCT study cited above observed, PHEV's “real fuel consumption is two to four times higher than the test-cycle values.”

Future Technological Developments

While EV technology and battery efficiency is improving every year, there are far fewer advances for PHEVs. As electric vehicles increasingly become the focus of auto manufacturers and as emissions standards are toughened, PHEVs could be phased out as too expensive.

Once electric vehicles reach price parity with PHEVs and fossil fuel vehicles and charging infrastructure is expanded, it is likely that PHEVs will vanish from roads.

Some automakers have already announced this intention. In 2019, facing declining sales in PHEVs, Volkswagen and General Motors announced plans to cut their development of PHEVs and turned their attention to EVs. In 2021, Ford announced that it would sell only EVs and PHEVs (in Europe) by 2026, and phase out PHEVs by 2030.

It seems increasingly clear that the future of transportation is fully electric.

View Article Sources
  1. Hall, Dale and Nic Lutsey. "Effects of Battery Manufacturing on Electric Vehicle Life-Cycle Greenhouse Gas Emissions." The International Council on Clean Transportation.

  2. Knobloch, Florian, et al. “Net Emission Reductions From Electric Cars and Heat Pumps in 59 World Regions Over Time.” Nature Sustainability, vol. 3, 2020, pp. 437-447., doi:10.1038/s41893-020-0488-7

  3. Plötz, Patrick, et al. "Real-World Usage of Plug-In Hybrid Electric Vehicles: Fuel Consumption, Electric Driving, and CO2 Emissions." The International Council on Clean Transportation, 2020.

  4. Burnham, Andrew, et. al. "Comprehensive Total Cost of Ownership Quantification for Vehicles with Different Size Classes and Powertrains." Argonne National Laboratory, U.S. Department of Energy, 2021.

  5. "Fuel Economy Guide 2021." Environmental Protection Agency.

  6. eGallon: Compare the costs of driving with electricity. U.S. Department of Energy.