Europe has been loyal to diesel cars for decades, but it seems that loyalty is now starting to fade.

Diesels have been popular because of their high fuel economy, but as the public has become more aware of their adverse effects on air quality, there have been more concerted efforts to find alternatives.

The shift is now apparent in the major U.K. business of company-car leasing, in which businesses lease fleets of cars for their employees.

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Cars with downsized gasoline powertrains as well as hybrid and electric cars are gaining ground on diesel in the U.K., according to WardsAuto.

This change was documented in a study by car-leasing company, which compared lease data from the first seven months of 2016 to the same period last year.

Between January and July 2015, diesel cars accounted for 86 percent of lease deals, with gasoline cars at 12.8 percent, and hybrids and electric cars accounting for 1.2 percent.

2017 BMW 3-Series

2017 BMW 3-Series

In comparison, the data for January through July this year showed diesel at 79.3 percent, gasoline at 17.6 percent, and hybrids and electric cars at 3.1 percent.

The top gasoline models leased during that period included variants of the BMW 3-Series, Renault Clio, Seat Ibiza, and Volkswagen Scirocco.

The firm points to everything from the Volkswagen diesel scandal to more-efficient gasoline engines eroding diesel's cost advantage as likely factors in the switch.

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In addition, the most efficient diesel cars can no longer enter London's Congestion Charge zone without paying the fees levied on other cars during weekday business hours.

These diesels—as well as hybrids—lost that privilege in June, when London fully implemented stricter emissions limits for its congestion-charge exemption.

Pretty much the only cars allowed in for free now have plugs.

2016 Renault Clio RS

2016 Renault Clio RS

This is the second recent study to indicate that U.K. businesses are moving away from diesel.

Another conducted by lease- and fleet-management company Arval predicts the number of diesel cars in U.K. business fleets will decrease 5 percent by 2021.

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That trend will be helped if a prediction by Nissan that electric-car charging stations will outnumber fuel stations in the U.K. by 2020.

The number of stations dispensing fossil fuels has declined since the 1970s, Nissan notes, while the number of charging stations has risen in recent years.

The carmaker expects that 7,900 charging sites will be live in the U.K. by August 2020.


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