Reducing Carbon Dioxide Emissions in Transport Infrastructure Projects

Abstract: On- and off-site construction activities during transport infrastructure projectsare major contributors to greenhouse gas (GHG) emissions. The SwedishTransport Administration (STA) has stated the goal of gradually reducing itsemissions from transport infrastructure projects to zero by 2050. However,current life cycle assessment (LCA)-based approaches for estimating GHGemissions are static and location-independent, and thus do not account for thedynamics of construction. Some project-based methods have been proposed,but there is little guidance and insight available to facilitate theirimplementation in real projects during project planning.This thesis aims to explore how CO2 emissions can be reduced during differentstages of the planning process for transport infrastructure. The analysis focuseson emissions during project execution, i.e. on- and off-site constructionactivities including material production, and transportation. An exploratoryresearch approach is used to develop practical CO2 reduction methods thatcould be implemented during the feasibility studies, the design stage, and theprocurement stage of the planning process. These methods and models aredeveloped and demonstrated in case studies. This is a similar to the prototypingmethod in which early drafts of a new system are developed and tested toenable further development into a finalized system. The findings show thatconsiderable CO2 reductions can be achieved if project alternatives areevaluated systematically during the planning process. Although most majordecisions are made during the early stages of the planning process, later stagesshould not be ignored because these offer opportunities to include moredefinitive project data and thereby improve the certainty of the assessments.Future research in this area should look at the entire planning process up to thestart of construction.