QINGDAO -- Smart dustbins have become popular in East China's Qingdao city.

Shibei district in Qingdao, Shandong province, has installed the special dustbins in several subdistricts since December las year, where residents can earn money by throwing garbage into categorized bins.

In a square in the Hailun Road subdistrict, resident Wang swiped a card on one of the three blue dustbins labeled "paper." As the door opened, Wang put some old newspaper in it, which showed the paper's weight and price. After swiping the card again, the doors closed, and about 3 yuan ($0.48) was transferred into her account.

"Here, old newspaper is worth 1.1 yuan per kilogram, higher than what retailers offer," Wang said.

The dustbins are part of local government efforts to encourage garbage sorting by offering rewards. Residents can use the cards for shopping in designated supermarkets.

Qingdao, a coastal tourist city, has been struggling to keep its garbage sorted, as locals are used to putting trash such as waste paper, glass and kitchen waste into one bag and throw it into dustbins, bringing trouble for waste collection, sorting, recycling and treatment.

Nearly 2,900 residents in the district have registered for the trial program, bringing in more than 1,000 kilograms of recyclable wastes on an average day, according to district officials.

The dustbins mainly recycle paper, plastic bottles and old clothes. The program will be extended to cover other trash such as old electronics and expired medicine, the officials said.