An Energy Efficiency Aggregator can have different functions and roles including attracting customers, aggregating a sufficient number of buildings together into an energy savings portfolio, monitoring and evaluating the criteria for joining and selecting the projects, looking for investors and defining an energy efficiency programme. The H2020 SENSEI project has launched a survey to help in developing the Energy Efficiency Aggregator business model and support the replicability of Pay-for-Performance schemes in the EU. The questionnaire aims to provide a better understanding of the following questions: What kind of services are expected from the Energy Efficiency Aggregator business model? What are…