Teschler on Topic
Leland Teschler • Executive Editor
[email protected]
On Twitter @ DW_LeeTeschler

The 2021 United Nations Climate Change Conference, also known as COP26, recently convened in Scotland. Perhaps unsurprising to cynics, soon after COP26 came an analysis from the Washington Post that found a significant gap between the amount of greenhouse gases countries say they emit and what they’re really putting into the atmosphere.

There are many facets to this so-called greenhouse gap, but one of the more interesting items concerns plug-in hybrid vehicles, or PHEVs. A PHEV has both a combustion engine and an electric motor, like an ordinary hybrid. But the battery in a PHEV is much bigger, allowing a PHEV to drive much further on electric power alone. But the bigger battery can’t be recharged by the car as it drives along like a regular hybrid. Instead, you have to plug-in a PHEV to recharge it as with a full-blown EV.

PHEVs are claimed to put out less CO₂ than ordinary combustion vehicles. And that brings us to tests run by Transport & Environment, a European environmental group, that reveal PHEVs pollute significantly more than carmakers claim. T&E says a big part of the problem is the use of weak electric motors and slow charging speeds. Worse, manufacturers challenged on these issues often blame the excessive CO₂ output on consumer driving habits.

Problems arise once the PHEV combustion engine kicks in. PHEVs that T&E tested could only drive about 11 to 23 km (roughly 7 to 14 miles) in engine mode before they overshot their official CO₂ emissions per kilometer. T&E’s results also showed that even in optimal conditions, the tested PHEVs emitted 28 to 89% more CO₂ than during EU regulatory tests. When the combustion engine kicked in, emissions were comparable or worse than equivalent combustion-engine cars.

T&E claims that regulatory tests “fail to account for real-world driving conditions where the engine may come on even if the driver has requested the car to drive electrically. They also use unrealistic assumptions on the share of electric kilometers driven by PHEVs which have been shown time and time again to not reflect their real world use. This allows manufacturers to claim unrealistically low CO₂ emissions for these cars.”

T&E looked at the real-world emissions of 20,000 PHEVs and found that rather than emitting an average of 44 g CO₂/km (the figure arrived at in lab tests) most PHEVs actually emit over 2.5x as much when driven on the road. T&E also points out it is almost impossible for a PHEV to regularly drive in zero-emission mode even for short distances.

Of course, the extra CO₂ comes from the need for PHEVs to burn petrol. These results might help explain a puzzling situation in Norway where almost two-thirds of new vehicle sales are now some kind of EV. (In the U.S., about 2% of new vehicles are EVs.) Yet according to a study by the banking firm Morgan Stanley, oil consumption in Norway basically has been stable. And by extension, we might infer the same for Norway’s CO₂ emissions.

Norway’s experience doesn’t bode well for the likelihood of reducing worldwide CO₂ output. The wealth management firm Evergreen Gavekal points out that though petroleum consumption in the developed world has largely flatlined over the past decade, China’s oil demand has vaulted by about six million barrels daily since 2010. And by 2031, an estimated one billion Asian consumers will work their way into the middle class and likely consume more energy than they do today.

Evergreen Gavekal further says that despite the exponential growth of renewables over the last 10 years, every fossil fuel category has seen increased usage. And even if China gets up to Norway’s 64% EV market share of new car sales over the next decade, it will probably use a lot more oil, not less.

Taken together, these developments imply it pays to be skeptical about the headlines coming out of COP26 touting lower CO₂ emissions. DW

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