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Annika Carlsson Kanyama and Greger Henriksson inspect waste storage rooms at KTH Campus. (Photo: Marc Femenia)

Researchers aim to reduce food waste

Published Dec 08, 2017

Deal with the food that is discarded but ensure less food is wasted in the first place. Researchers Greger Henriksson and Annika Carlsson-Kanyama have lots of ideas about how KTH Royal Institute of Technology can improve its environmental performance. Join them on a visit to a model waste storage room and another where there’s room for improvement.

Greger Henriksson, researcher at the Department of Sustainable Development, Environmental Sciences and Engineering (SEED), and environmental representative at the School of Architecture and the Built Environment, peels an orange in the coffee room. He throws the peel into the organic waste container under the sink. There’s a bin in the next cupboard for household waste that cannot be sorted.

“It’s empty; that’s a good sign,” says Henriksson contentedly. “All food waste in the building is collected and used. If you eat a piece of fruit at your desk, for example, you can save what’s left over in your own biogas mug that you can empty later.”

Greger Henriksson in the staff kitchen.

The sorted waste containers are usually emptied by the departmental cleaners, but on this occasion Henriksson takes the brown bag and shows us to the waste storage room at Osqars backe 3, which belongs to the School of Architecture, IT Support and the School of Computer Science and Communication (CSC).

We are joined by Annika Carlsson-Kanyama, a researcher in industrial ecology in the same department. While Henriksson focuses on what happens with the waste, she looks specifically at what happens before food is thrown away.

“We could make the whole campus an experiment in making use of food that is otherwise wasted – ‘Save food at KTH’,” she says. “Ideally this would involve an app, as we’re an institute of technology after all. We could offer people food that’s left over from catering or that we haven’t used at home.”

Food from strangers

Annika Carlsson-Kanyama says that a town in Australia tried a “leftover swap”, but people found it difficult to accept food from strangers.

“On the other hand, it has been found that people are prepared to share when they know the person who’s giving the food away. People ought to be happy to accept food from their colleagues.”

When Greger Henriksson opens the lid of the bin for food waste, there’s a swarm of fruit flies. But the waste storage room is clean and tidy and there is no intrusive smell. This certainly is an example of how a waste storage room should be kept.

“The caretaker and cleaner work really hard to keep it in good shape,” he says.

Waste can be sorted into several different containers. Even environmentally hazardous waste such as metals, energy-saving light bulbs and spray cans can be dealt with, and at the back of the room there is a crusher for cardboard boxes and corrugated board.

Sorting at source at SEED.

The bottom of the paper sack for food waste is wet, but this isn’t a problem.

“When the waste management company comes and collects the food waste, they take the bin outside and empty it all out,” says Greger Henriksson. “After that you can just wash the whole room out.”

Fuel for buses

The food waste is taken to a biogas plant in Huddinge, where it undergoes a digestion process and is converted into 97 percent non-fossil methane and organic fertiliser. The vehicles using the gas include approximately 2,500 taxis and 328 municipal buses in Stockholm. The fertiliser is used by organic growers.

It was Greger Henriksson who found out that there were redundant bins for waste food sitting on a shelf in the waste storage room. He brought the bins out and the university’s property management company Akademiska Hus helped him to arrange for them to be emptied.

Prior to that he would collect rubbish from his department and personally leave it outside KTH for collection by Stockholm Vatten och Avfall, the waste management company. Annika Carlsson-Kanyama wonders how we are to achieve a sustainable society when making the necessary practical arrangements can be so difficult.

“It’s not actually difficult, of course, but in this case it needed Greger to come here and get things organised. Sometimes things move unbelievably slowly, don’t they?”

“Yes, but for people who are determined, like you and me, this can act as an incentive,” replies Greger Henriksson, stressing at the same time that it is important that all the links in the chain are in place.

“Lots of different groups of employees are involved in dealing with food waste, including administrators, lecturers, researchers, caretakers and cleaners from KTH, plus staff from Akademiska Hus.”

Solution for enthusiasts

The next waste storage room is in the School of Architecture and the Built Environment at Brinellvägen 1. There is no bin for food waste. The room smells of rubbish and the floor is dirty.

Waste storage room with room for improvement, in Greger Henriksson’s view.

“If the room is not properly looked after, you get a permanent smell,” says Greger Henriksson. “This needs a thorough clean and an overhaul. Even though the room is small, that would then give you a clean, practical space.”

When he worked in the building previously, he thought at first that the reason that waste did not get sorted was that there were no containers upstairs in the department.

“But then I thought, ‘Hang on, the waste storage room is open and we can take our rubbish downstairs just as we do at home’.

It’s a solution that will appeal to enthusiasts – other people will need support,” says Annika Carlsson-Kanyama. “Also, management has got to demonstrate that it’s a priority.”

Greger Henriksson agrees, although he does think that it’s quite easy to take the lift down, or even go across the street to the university administration building where there is already a bin for food waste.

“A lot of this is about getting the practicalities right. Small things like making sure people can access the waste storage rooms using their passes. We need to set things up so that it’s easier to sort waste than not to.”

Text: Ann Patmalnieks

Less waste – more sorting at source

Amongst KTH’s sustainability goals are a reduction in the volume of waste and an increase in waste sorted at source. The project involving the collection of food waste at the Department of Sustainable Development, Environmental Sciences and Engineering (SEED) is one of KTH’s pilot projects. The university administration has also been running a similar project, which is now to become permanent.

“We worked very closely with our cleaners and caretakers,” says Jannica Häggbom, environmental coordinator at the KTH Sustainability Office and project manager for the waste project. “There were a few things we had to tweak a bit as we went along. For example, it turned out that it was best to let the caretakers empty the coffee grounds from the machines separately and let the cleaners take care of the other waste.”

Any Schools interested in taking action on food waste can contact the KTH Sustainability Office  for support and recommendations as to how to go about it. A third pilot project on sorting waste at source is underway at the School of Technology and Health (STH). KTH has also ordered some specially designed and sturdy waste sorting containers for undergraduate buildings.