The design - a steel shelf with holes - can be attached to city bins to collect up to seven bottles or cans. This saves them being thrown into the bin or left on the floor.
These drinks containers, worth between 8 and 25 cents each in pfand, a deposit paid by customers, can then be picked up by collectors, who can take them to a machine to claim some cash.
The idea was the brainchild of young Cologne-based designer Paul Ketz, who wanted to create a solution to make pfand collecting an easier and less unpleasant task.
The 25-year-old inventor also spotted the potential benefits for the environment, with more rubbish reaching the recycling plant.
Ketz won the federal prize for eco-design in 2012 with his product, which judges said “looks good and helps both people and the environment.” Since then, he has been inundated with requests from local councils keen to cut waste management costs.
But it was the Bavarian town of Bamberg that made the best bid. Local authorities say collecting pfand can be an important source of income for the city’s poorest and they were intrigued by the contraption.
“There are those who depend on the bottle money, or at least earn a bit of extra income from it,” said Bamberg town council spokeswoman Ulrike Siebenhaar. “We think it’s degrading that people have to dig around in bins.”
Ketz's is not the only design aimed at making life easier for pfand collectors.
Hamburg-based company Lemonaid now include a list of instructions for transforming used crates into collection boxes that can be fixed to a lamppost. Over 300 of the crates were ordered from the company and they soon began popping up all over Germany.
Several boxes were put up by concerned citizens in Munich, where they were tolerated by the council, as long as no-one objected.
The crates also took off in Bamberg, but unfortunately they had not been designed to last. The boxes were not durable - they broke quickly and were not weather-proof.
Ketz's shiny steel rings on the city's bins have proved a more sustainable, yet expensive option. They were installed at a total cost of €1000, an investment the council is hoping will pay off for both citizens and recycling units.
Both the city and the inventor are hoping the new project, on trial for a year, will allow collectors to earn some extra cents without getting their hands dirty.