Over half of the population of the world live in
urban areas. This means that efforts to meet human
development goals and sustain economic growth
must be concentrated in cities. However, the pursuit
of more prosperous, inclusive and sustainable urban
development is complicated by climate change, which
multiplies existing environmental risks, undermines the
effectiveness of existing infrastructure, and creates new
resource constraints.
In this paper, we conclusively demonstrate that there

Green building is an important measure to deal with energy and environment problems in the construction sector of the world. In this study, knowledge mapping analysis is used, and 3,060 articles are selected for further study (1900–2019). Based on CiteSpace (5.3.R4 SE 64-bit), the knowledge base, hot topics and research trends of green-building-related research are presented. The key highlights of the overall analysis results are: (1) Research on green buildings has received more extensive attention in the 21st century.

This report is the first report of the ‘Energy Savings 2030’-project which seeks to help the Coalition for Energy Savings to produce a robust and timely input to the 2030 policy discussion. It brings together and summarises recent empirical evidence on costs and benefits of energy efficiency measures. The evidence gap in terms of reliable ex-post data is well known. In the majority of cases results from ex-ante modelling studies inform the debate. The research carried out for this report confirms the persistent gap in publicly available ex-post evaluations of energy efficiency programmes.