Mayor Bloomberg is asking city residents to unplug their cell phone chargers when they are not in use, carry a cloth tote bag to the supermarket, and buy new fluorescent lightbulbs.

Those are just a few of the 10 energy-saving tips Mr. Bloomberg was out promoting yesterday as part of a new marketing campaign the city is launching called “GreeNYC.”

The public awareness campaign — which will include donated television and radio commercials, as well as print and bus shelter advertisements — is part of a larger goal the mayor has set of cutting the city’s greenhouse gas emissions.

Mr. Bloomberg, who said he has started unplugging his BlackBerry charger when its not in use, said that in an average home, 40% of all electricity used is consumed while electronic devices are turned off but still plugged in.

While compact florescent bulbs cost a little more, he said, they are a good financial investment because they use 66% less energy and last longer, which translates into lower energy bills. If all households in the city replaced 75% of their bulbs, the energy savings could run all of the subways and light the stations, he said.

The advertising campaign also will urge New Yorkers to switch to electronic bank statements and energy-friendly appliances.