Mari Hupponen

The ongoing trend in the public sector is to make more sustainable procurements in order to take into account the impacts throughout the entire life cycle of the procurements. Despite the trend, the only deciding factor can still be the sum of costs. The research is related to the greenhouse gas emissions (CO2, CH4 and N2O) of municipal solid waste management. The aim is to answer how greenhouse gas emissions should be taken into account in the planning and decision making of waste management. The aim is also to guide the public procurement of the waste management towards more environmentally friendly procurements. The idea is to recognize the main processes that are affecting the results by doing life cycle assessments. The life cycle of waste begins from the moment the waste is produced and continues until the waste is utilized or landfilled. Avoided emissions resulting from recycling and energy recovery are also included. The GaBi life cycle modelling software is used as a modelling tool. The research focuses on different waste fractions, e.g. source separated mixed municipal solid waste, biowaste, cardboard, plastic, glass and metal. Different case areas and scenarios are used to evaluate the global warming potentials.