It pays little to commuters but Istanbul municipality's program of giving bus fare in exchange for depositing bottles has helped the city save a great deal in recycling. Since it was launched on Oct. 1, 2018, "smart" recycling containers saw the collection of 4.1 million bottles equal to 75,000 kilos, the Hürriyet newspaper reported. In exchange, commuters topped up their IstanbulKart, the electronic passes for mass transit, a total of TL 179,543.

Istanbul has one of the highest rates of waste production as it remains the country's most populated city with a population of over 15 million people tucked into two small stretches of land divided by a waterway.

The municipality adopted the bus fare for waste scheme last year as part of its contribution to the Zero Waste Project, an ambitious program launched by first lady Emine Erdoğan to maximize nationwide recycling efforts. The reverse vending machines feature an electronic interface that is able to recognize and sort out the waste discarded and crush, shred and store it. By depositing an eligible container, plastic bottles or aluminum waste etc., commuters receive refund credits on their IstanbulKart.

Istanbul produces an average of 17,000 tons of domestic waste every day, out of which 6,000 tons are processed in the municipality's garbage collection and recycling centers. One recycled plastic bottle produces enough energy to power a 60-watt light bulb for a few hours.

The project helped with the collection 3.4 million of plastic bottles and 675,000 aluminum cans. The exchange is low as the smallest plastic bottle gives TL 0.02 in return and the highest credit for the IstanbulKart in return of waste is TL 0.9. Still, the high number shows that commuters are eager to contribute to recycling no matter how small the benefit.