In Sønderborg lies Alssund Gymnasium. On a daily basis, the school houses 400 students and an additional 50 employees. Alssund Gymnasium stands out from other high schools by having a pronounced commitment to the green transition. Since 2010, the school has been an active part of the Friluftsråd (Council for outdoor activities) "Green flag - green high school" project. This project is marked annually with the hoisting of a green flag on the school, which marks that the school's students and staff are once again involved in sustainability initiatives and the green transition.


The school works on projects that are tailored to the UN's sustainable development goals and in addition, the school also has a notable focus on how the green transition can be passed on to the local community. 

For the last two years, Alssund Gymnasium has held a climate folk meeting for high school students. Here, the focus on the green transition in teaching arecommunicated and discussed among the participating students. The purpose of this day is to give different perspectives on the climate and sustainability debate. 

As part of the continuous focus on the green transition, Alssund Gymnasium has also installed solar panels. The solar panels have since been connected to a redox flow battery from VisBlue. With this installation, the school can now look forward to increased use of their solar energy. This will result in a significant annual savings on the electricity bill, as the school will have far less need to draw power from the electricity grid. Practically, the redox flow battery stores surplus solar energy so that the school can use this power during periods when the sun is not shining. For an institution like Alssund Gymnasium, where there is not a lot of activity on weekends and holidays, a redox flow battery can turn out to be a very sensible investment. During these periods, consumption is low, but the solar panels will still produce energy. This energy can now be stored and used when the school opens again. 

The collaboration between Alssund Gymnasium and VisBlue should serve as a shining example that the green transition and focus on the climate is not necessarily associated with expenses. The redox flow battery has a lifespan of 20+ years and can thus save the high school from high operating costs in the future.