Life Cycle Costing Model for Solid Waste Management

To ensure sustainability of solid waste management, there is a need for cost assessment models which are consistent with environmental and social assessments. However, there is a current lack of standardized terminology and methodology to evaluate economic performances and this complicates the performance of new studies as well as the understanding of similarities and singularities between the different types of cost assessment applied in literature. This investigation develops a systematic framework for performing various types of cost assessments with different cost perspectives. Most of the cost assessments in literature can be classified into: 1) Conventional Life Cycle Costing (LCC), 2) Environmental LCC and 3) Societal LCC. While the first two LCCs are financial assessments, the third one is asocio-economic assessment. The three LCCs included marketed goods, but they handle differently nonmarketed goods (i.e. externalities). While non-marketed goods are beyond the scope of the Conventional LCC; the Environmental LCC included environmental externalities in a parallel LCA and the Societal LCC internalizes all the externalities into monetary terms. Different cost perspectives can be applied in each LCC, e.g. waste generator, waste operator and public finances and the perspective often defines the systemboundaries of the study, e.g. waste operators often focus on her/his own cost, i.e. technology based,whereas waste generators and public finances often focus on the entire waste system, i.e. system based. Figure 1 illustrates the proposed modeling framework that distinguishes between: a) budget cost, b) externality costs and 3) transfers and defines unit costs of each technology (per ton of input waste). Unitcosts are afterwards combined with a mass balance to calculate the technology cost. Later, the costs of individual technologies can be combined to calculate the system or scenario costs. In the technology definition, each cost item is defined with a unit cost per item, which is calculated with two types of parameters: 1) economic (e.g. unit prices and depreciation periods) and 2) technical (e.g. usage rate andconsumptions of commodities).The investigation provides an overview of which cost items should be included in each pair of LCC perspective and common calculations to estimate technical parameters for main waste technologies. The applicability of the cost assessment model is illustrated with a fictive case study focusing on source segregation of organic waste in Denmark.