Wang Yali is busy packing her groceries at a supermarket as usual. However, something is different today: she doesn't put her goods into plastic shopping bags, but stuffed them all into her own bag.

From Sunday on, all Chinese retailers, including supermarkets, department stores and grocery stores, will no longer provide free plastic shopping bags. China is trying to reduce the use of plastic bags in a bid to reduce energy consumption and polluting emissions.

"It doesn't matter how much the plastic shopping bag costs. What matters is our sense for environmental protection," Wang said.

"Customers are encouraged to carry their own bags," an official with the Ministry of Commerce, Men Xiaowei, said in an on-line interview earlier. "It is a 'habit revolution.' To limit the use of plastic bags is to protect our environment."

Chinese have enjoyed free plastic shopping bags for more than a decade. Those shopping bags used to bring lots of conveniences to Chinese shoppers. However, they also caused a heavy burden to the environment.

According to an estimate by the National Development and Reform Commission (NDRC), the country's top economic planner, each two people would consume one plastic bag in one day. At least 1,300 tons of oil would be consumed daily to produce the shopping bags for supermarkets alone.

In addition, China has banned ultra-thin plastic bags, or those thinner than 0.025 mm.

"Plastic bags are difficult to be degraded," Men said. "The plastic waste accounted for more than 3 to 5 percent of the daily waste, most of which came from plastic bags."

Retailers have begun to charge fees, ranging from 0.2 yuan (0.02 U.S. cents) for small sized plastic bags to more than 10 yuan for fabric ones, for the shopping bags.

Many supermarkets, including Wal-Mart, Carrefour and Jian-Mart, have established green paths for those carrying their own bags.

Retailers providing free plastic bags could be fined up to 10,000 yuan

Retailers are free to set prices for shopping bags. However, they must not be cheaper than the costs.

"Retailers worried that they might lose customers if they charge too much for shopping bags," Men said. "But our goal is to reduce the use of plastic bags. The selling price of plastic bags must not be cheaper than their costs."