Drivers are being warned they could be faced with a fine if they leave their engines running in the street.
Initially the fine could be £20 but may double to £40 if not paid on time.
Engine idling is illegal under Section 42 of the Road Traffic Act 1988 which means starting your engine to defrost your window could get you into trouble.
Speaking to The Daily Express, Andrew Marshall, marketing and partnerships manager at CarMoney urged drivers to cover their windows overnight to prevent ice.
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.”
However, experts at Confused.com added that these rules only apply to public streets, so you’ll be ok to defrost on your driveway.
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.”