Application and problems of emergy evaluation: A systemic review based on bibliometric and content analysis methods

•Application and problems with emergy evaluation are analyzed based on 886 papers.•Bibliometric and content analysis methods are used to study the topic.•The EME has been undergoing rapid development over the last several decades.•Methodology improvement to the EME has been a popular topic since the 1990s.•Advanced methodology is required for increasing operational level of the method.