Supporting the EU Mission “100 Climate-Neutral Cities by 2030”: A Review of Tools to Support Decision-Making for the Built Environment at District or City Scale

Human activities are responsible for vast environmental impacts, including carbon emissions contributing to climate change. The urban environment is a main source of many of these impacts, and accordingly, the European Union has launched the “100 climate-neutral cites” mission to operationalize a carbon-free urban future. This paper investigates the various evaluation tools supporting the Decision-Makers (DMs) and stakeholders in their effort to achieve the carbon-neutral transition. Using the scientific database Scopus, we conducted a literature review focused on different keywords comprising widely used evaluation methods. The focus of the research is on different aspects and scales of the urban systems, considering the multi-dimensional nature of the decision problems at such scale. Specifically, the study presented here analyzes the way in which these methods deal with large scales, either with a bottom-up or a top-down approach, and how different categories of Key Performance Indicators (KPIs) and changes in the DMs system of values can influence their preferences. We find that Lifecycle Assessment (LCA) is the most used support tool at the district or city level, and most indicators focus on energy consumption and carbon emissions. A smaller share of studies reviewed are based on multi-domain evaluation methods.