Low-carbon urban experiments from vision to reality: a systematic review of the literature from 2005 to 2020

In recent decades, many cities have launched low-carbon pilot schemes to explore feasible local policies and actions that can be replicated on a larger scale to reduce the intensity of carbon emissions. This synthesis analysis reviews the global literature to analyse the interplay of prescriptive visions, practical responses, and evaluation methods of low-carbon urban experiments. Before 2015, low-carbon urban experiments were regarded as a sub-branch of sustainable development, and prescriptive visions were influenced by sustainability. Low-carbon urban experiments were used as an urban planning tool, and such urban planning concepts impacted the practical response and evaluation methods. After 2015, low-carbon urban experiments were influenced by many more disciplines. Planning still occupies the largest proportion of low-carbon practices, but more advanced technologies - in energy and other fields - have also been adopted and influence the evolution of low-carbon urban experiments. We find several driving factors, including political events and developments, technology change, and contributions from various disciplines including academic research. As carbon neutrality is the long-term target of many nations, achieving net-zero carbon dioxide emissions through prescriptive visions, practical responses, and evaluation methods in urban experiments demands further investigation, especially in developing countries.Key policy insightsLow-carbon initiatives on a small scale are frequently practiced by local and national governments, which has reshaped the low-carbon agenda worldwide.Low-carbon development also demands efforts and commitment on the part of local urban governments to promote low-carbon development in its multiple dimensions.Policymakers at different levels of government and governance should focus on how to build on policy instruments in experimental pilots to take action at broader scales.Policymakers also need to adopt relevant indicators from social science in evaluation methods to reflect social sustainability and inclusiveness concerns in the evaluation of low-carbon urban development.