Plug-in hybrid cars burn far more fuel than official tests record, according to a study that shows pollution from the vehicles could be significantly worse than advertised.
Tests of plug-in transmission electric vehicles (PHEVs) by Which ?, the UK consumer group, found that some popular cars achieved as little as a third of the fuel economy advertised in official tests.
Cars made by BMW, Mercedes-Benz, Mitsubishi, Volkswagen and Volvo were among 22 that were found to burn 61% more fuel than in official tests.
The worst player was the BMW plug-in hybrid SUV X5. He achieved 188.3 miles per gallon in official tests, compared to just 52.8 miles for Which ?. That 72% efficiency difference could put more than £ 650 a year in petrol costs, the group said.
The additional fuel burned would provide more carbon dioxide emissions, as well as running costs for owners. The average additional cost was £ 462, What? measured.
Plug-in hybrids combine an internal combustion engine with an external rechargeable battery, in hopes of reducing CO emissions2 and other pollutants while also providing fossil fuel range and refueling.
However, the environmental benefits of PHEVs – often equipped in bulky SUVs – are controversial. The car industry argues that they are an important stepping stone for some consumers to switch to fully electric cars, but some environmentalists argue that cars can be greener than those without a battery unless they are rebuilt regularly.
Hybrid graphic
All cars sold in Europe are, by law, required to be tested in accordance with a worldwide compatible light vehicle (WLTP) test method. What? argues that they do not accurately reflect driving conditions in the world, and therefore test cars over long distances while using air conditioning and the radio, as well as PHEVs run for portions of its tests with an empty battery.
Greg Archer, UK director of Transport & Environment, an enterprise agency, said the results of an official fuel economy test and emissions were “a real breakdown”.
He said: “The engine in most PHEVs turns when the car is accelerating hard, or the driver turns on the heater or air conditioner. Most PHEVs have such a small battery that the car can only travel about 30 miles with zero emissions and cannot be charged quickly. Owners who want to reduce their running costs, or opt for a green car, should choose a battery-powered electric model. ”
PHEVs accounted for 58% of recurring cars sold in the 18 largest western European markets in January, according to data from Matthias Schmidt, a Berlin-based electric car analyst. Plug-in hybrids will be more popular than traditional indoor combustion cars because of tax and subsidy benefits, he said.
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Cars are also a key part of carmakers’ strategies to cut their average carbon emissions and avoid sharp fines. Volkswagen and Jaguar Land Rover, the UK’s largest car employer, are among the drivers set out to pay millions of euros for breaking EU targets in 2020.
What? send its findings to all car manufacturers whose results have been tested. Respondents indicated that PHEVs can reduce emissions if reintroduced as suggested.
Mike Hawes, chief executive of the Association for Motor Manufacturers and Dealers, a UK industry lobby group, said car owners were only allowed to publish WLTP data.
He said: “WLTP tests consistently show that plug-in hybrids offer a comparable range to petrol or diesel equivalents but deliver significant emission reductions, with a zero emission range typically 25-40 miles, which is more than enough, as 94% of UK car journeys are less than 25 miles. “