Reducing the carbon footprint of municipal infrastructures

Abstract

Developers of municipal infrastructures have focused so far mainly on the operation of infrastructure networks (e.g. roads) or facilities (e.g. district heating facilities) and their impacts on climate change. Only recently, the focus shifts to optimizing CO2 emissions embodied in building materials and caused by processes and transports related to construction, maintenance, overhaul and renewal of civil engineering works. The European standard EN 15643-5:2017 provides specific principles and requirements for the assessment of their environmental performance and a new standard for calculation methods will be published in 2022 including an assessment of embodied C02 emissions. But, how can this information be used to systematically reduce the carbon footprint for municipal infrastructures? In an ongoing research project, we want to answer this question and develop a management cycle for optimizing the carbon footprint of municipal infrastructures. In a first step, we used expert interviews with infrastructure operators, planers and builders focusing on roads to define use cases where information on embodied CO2 emissions is needed. In a second step, we studied construction projects (completed in the past) to analyze data availability at different stages of the planning process. Based on our preliminary results, a management cycle should include the following four use cases for using information on embodied CO2 emissions for decision support. First, it should be used for monitoring of infrastructure networks (as part of scope 3 accounting for operators). Second, it supports priority setting for renewal and overhaul planning when used to analyse representative project portfolios. And, it will help developing project specific benchmarks for optimization at early design stages as well as before public tender. In the next step of our project, we will adapt existing calculation methods in collaboration with operators of municipal road networks to meet information requirements in the identified use cases.