And fuel economy has now become a more important factor in determining car choice among the UK's vehicle buyers than a model's perceived glamour, the study adds.
"The rapid growth of the green agenda among car buyers over the last year is very significant," AA personal loans director Lloyd East said.
"With a fifth of all car buyers today going green, the environmental agenda is being driven into the heart of the motor industry - over family estates, saloon cars and people carriers," he added.
The same report claims that too many consumers are opting to take out showroom finance, instead of taking out a secured loan from an independent provider.
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