The purpose of this thesis is to investigate optimal utilisation of waste in a 100% renewable energy system in Denmark by 2050 while conform- ing to the concept of circular economy. This is relevant, because the EU has defined a set of recycling goals for Municipal Solid Waste (MSW). This, however, is one of the fractions utilised for energy purposes in Denmark, thus a change in the waste available is expected.
The waste resources available for energy recovery in 2050 has been identified through a literature review as part of a resource analysis. Furthermore, the Waste-to-Energy (WtE) technologies applicable for the available waste fractions are investigated. Based on the resources and the WtE technologies, a range of scenarios are constructed for analysis of possible realisations for the future Danish energy systems.
The scenarios are simulated in an energy system analysis by the use of EnergyPLAN and the model defined in IDA’s Energy Vision 2050. The scenarios are evaluated on their technical, environmental, and economic performance, where one of the constructed scenarios is found to be optimal. The barriers opposing the implementation of this scenario are identified and discussed. Mostly these are of a regulative nature.
The optimal use of waste in a future energy system is found to be production of gas, both from the biodegradable waste through anaerobic digestion and the residual waste through gasification. This utilisation will also secure high resource efficiency, energy independence, and security of supply.