More cold weather is expected in the coming weeks and drivers have been warned about leaving their car engine on to defrost their windscreen.
They may be hit with a £20 fixed penalty notice for leaving their engine idling on a street, experts have said.
And the penalty could rise to £40 if the charge is not paid within a specific time frame.
In London, new emissions rules mean this charge could rise to £80, the Express reports.
Andrew Marshall, marketing and partnerships manager at CarMoney, warned drivers were likely to idle their cars while defrosting their vehicle.
He has urged road users to “cover” their windscreen overnight or use a “can of de-icer and a manual scraper” instead of turning on their engines.
He said: “Now more than ever it is important to be aware of our impact on the environment.
“By minimising car idling on our daily commutes, school drop-offs and simply waiting in traffic, we can contribute less CO2 emissions.
“Aside from switching to electric vehicles or hybrid car models, motorists can be more mindful of their idling habits by switching off their engine if waiting for long periods of time.
“As winter approaches, lessen the need for idling whilst waiting for the windows to defrost by covering your windscreen overnight, or using a can of de-icer and a manual scraper to clear the windscreen.”
Engine idling is illegal under Section 42 of the Road Traffic Act 1988.
The Highway Code also clearly states drivers should never leave their engines on for no reason.
Rule 123 said: “You must not leave a vehicle’s engine running unnecessarily while that vehicle is stationary on a public road.”
The RAC has warned idling engines can produce up to twice as many emissions as an engine in motion.
They said this would “impact the surrounding area and the air that we breathe”.
However, experts at Confused.com warns the rules only apply on “public roads only”.
This means motorists can legally idle their engine on their driveway without facing any punishment.
They said: “The rules over stationary idling apply to public roads only.
“So you aren’t breaking the law if you idle in your drive, or in a supermarket car park, for example.
“However, just because it’s not illegal doesn’t mean it’s the right thing to do.
“You’d be chucking just as many toxic fumes into the air regardless of whose land you’re on.”
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