For the past five months students from the masters Industrial Ecology and Governance of Sustainability have worked on the Sustainability Challenge. In groups they chose a specific project in the field of sustainability, commissioned by an external organization. From NGOs to municipalities, and from local community initiatives to a national bank. 'With the Sustainability Challenge you step outside of your academic bubble.'
The projects are as diverse as the students working on them. The Master Industrial Ecology is a Leiden-Delft-Erasmus collaboration, which means that students from different fields of study work together on cases. A few examples of Sustainability Challenge projects:
1. Fungi Farmers: A network of fungi 
Fungi Farmers is a small company from Leiden that grows oyster mushrooms on collected coffee grounds in so-called "kweekcontainers". Circularity and working locally play a key role: ‘The residue from the cultivation process is used directly in the garden next to our container,’ says Inge, co-founder of Fungi Farmers and commissioner for the Sustainability Challenge.
Born from a fascination with mushrooms.'
As a startup, there are many challenges, Inge explains. Growing mushrooms is laborintensive, and coffee grounds, while an excellent waste stream, are very susceptible to mold, requiring expertise and precision.
That’s why the student’s project was to seek collaborations with other growers. ‘There are about 13 similar initiatives in the Netherlands,’ says Inge. ‘How do they tackle these challenges, and can we help each other?’ With a long list of contacts, the students got to work. They travelled across the country to visit different farms, performed interviews, and planted the seeds for a network. ‘It is fascinating to see how much creativity and ideas the students bring.’
2. Loods M: A place where old and new meet
About five months ago, a group of IE students first met with their commissioner Martine in Maassluis. They were introduced to Loods M, a network organization working on a cultural-educational-innovative hub in the city's old harbor area. This unique location brings together many different groups, or “Loodsgenoten” as Martine likes to call them. From artists to businesses, and from boat volunteers to city council members, ‘...Loods M allows these groups to collaborate and move away from a certain island-mentality,’ Martine explains.
How can we preserve our maritime heritage while contributing to a more sustainable future?'
That’s when the students came in. Their task? Building a smart energy network that can provide Loods M and the tugboats with renewable energy. But what started off as a technical challenge, soon turned out to be way more complex. Through interviews, the students realized that the social aspect was inseparably linked to the technical. What if the local residents do not want such a modern, smart energy system?
Opportunity to shape the project yourself
‘You go through so many phases in such a project: from an initial peak of enthusiasm, to feeling completely lost, to slowly putting back the pieces together,’ says student Kaatje Bout. ‘With such limited time you learn how to adapt quickly to face each new challenge,’ fellow-student Isa Huipen adds. The students also noticed the amount of freedom they received from their commissioner. Martine: ‘I wanted to give the students the opportunity to really shape this project themselves.’
With the Sustainability Challenge you step outside of your academic bubble.'
As a result, the students came with creative ideas to incorporate the social aspect into their project. The group proposed creating a podcast, allowing the Loodsgenoten to tell their stories and share them in an engaging way. ‘I have really seen them grow and become more independent,’ Martine proudly remarks. In February, the students will also present their results to the Loodsgenoten and the city council of Maassluis.
3. BNG: A bank building towards a circular future
This is the fourth year that Caspar Boendermaker, commissioner of BNG Bank, participates in the Sustainability Challenge. ‘It is just an hour a week for me, and we get so much in return,’ he says. This year's challenge for the students: How can we encourage our clients, the housing associations, to build more circular and with lower CO2 emissions?
Since BNG's clients are mainly in the public sector, the focus is on large 
sustainable investment projects. This is not always easy: ‘There is great interest from housing associations in building circularly, but this should not come at the expense of the social housing price,’ Caspar explains.
Diversity of expertise and backgrounds
Caspar highlights the diversity of expertise and backgrounds among this year’s group of students. ‘They pick up things easily and bring many ideas to the table.’ His role is mainly to provide them with contacts from the bank's network and additional data or information. Once a week the students come to BNG's office to work on the project together which increases group collaboration.
In addition to the symposium, the students will also present their results at BNG Bank.'
The students ultimately deliver a final report to both the university and the commissioner. ‘We have always been very impressed with what the students come up with in previous years.’ This is why, besides the symposium, Caspar also organizes a presentation at the bank for the students to share their results.
