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Glasgow on the road to becoming a circular city

Posted on 17 January 2017.

The Scottish city is positioning itself as a pioneering circular economy city. The first experiments are in the food and beverage industry.

Use bread waste in beer making - one of the ideas in Glasgow’s plan to become a sustainable city.

Glasgow has completed the Circle City Scan and is aiming to becoming a cutting edge circular city. Commissioned from Circle Economy, a Dutch company that advises local authorities on circular economy programs, the June 2016 Circle City Scan of Glasgow report is the result of an remarkable partnership between the city of Glasgow, the Scottish Government’s Zero Waste Scotland Plan and Glasgow’s Chamber of Commerce.

The ground-breaking study not only proposes solutions that reduce the city’s environmental impact, but also offers economic models. It pinpoints the high-tech industries that would make the city's economy more circular and outlines potential implementation strategies for the new business models.

In the UK's third largest city, with its population of almost 600,000, the economy is concentrated in three sectors - health, education and industry - which together account for 30% of its economic activity. The food sector was identified as having the greatest circular potential and so the pilot projects have been concentrated there.

This sector consumes 51% of the city's energy, generates more than 2,000 trucks of waste a year and more than any other sector is crying out for more sustainable solutions.

Four pilot projects

The plan was implemented in the form of four projects. In the bakery sector, 20% of the energy consumed is used by boilers that heat water and produce steam. But the heat from the ovens can be recovered and reused by boilers thanks to heat exchangers, producing energy savings of 15 to 30% and avoiding the emission of 700 tonnes of CO2 per year.

The second project is an experiment in aquaponics - a form of aquaculture combining plant and fish farming; the experiment has already been set up in one of the city’s restaurants.

The third idea concerns one of the city’s major activities: brewing beer. And once again it is out of the ordinary: use bread waste or residues in the brewing process by employing an ancestral fermentation technique. Just think about it - in Glasgow an unbelievable 200,000 slices of bread are wasted every day! The potential is enormous: 500 grams of unsold bread can help produce 4,000 liters of beer using this particular brewing technique which has been known since ancient times!

In the fourth and final pilot project, the residue from the barley grains used in beer-making are recovered and go into bakeries (where they can replace up to 50% of the flour), pharmaceutical products and food supplements.

All four projects not only economize on resources but also reuse waste in a perfect industrial symbiosis: the waste from bread-making goes to beer-making... and then goes back to bread-making! With the help of the Circle City Scan, Glasgow is becoming a truly pioneering Scottish circular city!