• Fleet operators of plug-in hybrids aren't charging their vehicles, telematics and fleet management firm Geotab said in a study.
  • PHEVs need regular charging to reap cost and fuel efficiency benefits. Without charging, they can pollute more than gas cars or parallel hybrids.
  • Average daily driving distance for delivery vans in the U.S. is just 68 miles, govt. data suggests.

Plug-in hybrids can, in theory, deliver the best of both worlds. They can run purely on electricity for 30-50 miles depending on the model, with similar neck-snapping acceleration as fully electric cars. In EV mode, the drive is quiet, stress-free and zero emissions.

When you want to munch miles, the gas engine switches on and then it’s all range, no anxiety. But there’s one problem: most PHEV owners don’t plug their cars in. In fact, a recent InsideEVs investigation revealed that even automakers have very little data around PHEV charging habits, or just won't say. 

In any case, it defeats the purpose of the technology and ends up harming the planet rather than benefiting it.

New data from telematics and fleet management company Geotab, obtained by Electric Autonomy Canada, revealed that fleets operating PHEVs have unintended consequences on emissions. Geotab analyzed 1,776 PHEVs used commercially.

It found that fleet operators in North America rely on gas for 86% of their total energy needs. According to the study, PHEVs delivered an average fuel efficiency of 1.6 gallons every 62 miles (100 km), translating to roughly 37 miles per gallon.

2023 Toyota Prius Prime

That’s only a shade lower than the average fuel efficiency of gas equivalents, which consumed 1.8 gallons every 62 miles or 33.1 mpg.

Many U.S. fleet operators are turning towards fully electric models. Amazon has already deployed over 15,000 Rivian-made Electric Delivery Vans. FedEx has started using the BrightDrop Zevo EDVs made by GM. PepsiCo is using the Tesla Semi in California. Meanwhile, some local governments in the U.S. and Canada are also adopting PHEVs, like Canada’s Department of Fisheries and Oceans, the New York City Department Of Sanitation with over 20 plug-in hybrid street sweepers and the City of Los Angeles, which had at least 46 PHEVs as of 2022.

Geotab’s findings are similar to a handful of other studies on the subject. The European Commission’s Directorate-General For Climate Action revealed early this year that the CO2 emissions of PHEVs were 3.5 times greater in real-world usage than what their WLTP tests indicated.

For PHEVs registered in 2021, WLTP results showed PHEVs emitted only 39.6 grams of CO2 per kilometer. In the real world, PHEVs were emitting 139.5 grams of CO2 per kilometer.

The European Commission said at the time: “The large discrepancy found for these vehicles between the real-world and the WLTP values shows that they are charged and driven in electric mode much less than how they were expected to be used and that assumptions used for calculating the WLTP test result do not hold in real-world conditions.”

Toyota RAV4 Prime PHEV
Toyota

The International Council On Clean Transportation had similar findings for PHEVs in the U.S. It said the real-world fuel consumption may be 42-67% higher than EPA’s estimates for light-duty PHEVs. That’s like carrying a Swiss Army knife but only using it as a paperweight. The implications of skipping the charging station extend beyond just bad mileage and emissions. It means fleet operators also lose savings and likely won’t see any benefits on vehicle maintenance in terms of cost and complexity.

On a positive note, PHEVs indeed deliver when you use them correctly. I drove a Lexus RX450h+ plug-in hybrid last month for a week and it delivered an efficiency of 71 mpg on a full tank of fuel and a fully charged battery pack. In mixed driving conditions, including city, highways, countryside roads and winding mountain tracks, it barely used the gas engine. When it did, the engine worked both ways, recharging the battery and sending power to the wheels.

Geotab’s findings were similar. The top quartile of fleet PHEVs where drivers were charging them regularly were 50% more fuel efficient than gas cars.

Amazon EDV

While private owners would need more education on this front, fleet operators require a proper strategy, experts say. “Having data and metrics is a way for fleet managers to take action on underperforming vehicles. It’s so critical to have that feedback loop,” Charlotte Argue, Senior Manager for Sustainable Mobility at Geotab, told Electric Autonomy.

Fleet managers could deploy tools like charging reports, compare efficiencies of fuel use versus electrical use and encourage their drivers to plug their EVs in after each session. It goes without saying that having access to charging stations would also help.

The report, however, makes it clear: if fleet operators are serious about cutting emissions, they’re better off going fully electric. With EVs, there’s no option to skip charging; drivers must plug in to keep rolling.

According to the Alternative Fuels Data Center, the daily driving distance for a delivery van or truck, for example, is just 68 miles in the U.S.—well within the range of most modern electric vans. (Of course, the equation changes for medium and heavy-duty commercial trucks.)

But as far as light-duty fleets are concerned, there are two ways to address the PHEV charging caveat: educate drivers on the importance of charging, or take the leap and go fully electric from the start.

Contact the author: suvrat.kothari@insideevs.com

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