This thesis investigates how decision makers can support households to increase source sorting of food waste. The study is focu- sing on the specific context of the Danish island Bornholm, with the purpose to work towards a circular economy and a Bornholm without waste.
Bornholm are set to implement source sorting of 12 different waste fractions in the households before the end of 2022. Food waste constitutes almost 50% of the total weight of household residual waste and is therefore an important fraction to separate to recover important nutrients and energy from. Source sorted food waste from Bornholm will be treated in an anaerobic digester, where bio- gas and fertilizer are produced. However, through the study we identified a lack of focus on the households’ role in the system and their crucial responsibility to source sort the food waste, to enable the recovery.
By combining practice theory, ethnographic methods and life cycle assessment in an empirical case study, the thesis shows how the practice of ‘sorting food waste’ can be established. But also, what barriers might come in the way and what the environmental benefits from recycling the food waste are. The study results in a set of recommendations to the local decision makers (ie. the waste management company) on the island, about how they can support the households to sort food waste.
It was found that from an environmental perspective it does matter to sort food waste and send it to biological treatment, even if it must be transported away from the island to do so. Furthermore, the results showed that information about what can be sorted as food waste, households’ willingness to sort and the right equipment (bin, bag, containers), are amongst the vital elements to establish the practice to reach a high sorting rate. Additionally, the study confirms that the combination of practice theory and life cycle assessment shows potential to create solutions that are both environmentally and socially sustainable.
Key-words: Waste sorting, food waste, Circular economy, life cycle assessment, practice theory, Sustainability, cultural probes