Le Dréau, JérômeLopes, Rui AmaralO'Connell, SarahFinn, DonalHu, MaomaoQueiroz, HumbertoAlexander, DaniSatchwell, AndrewÖsterreicher, DorisPolly, BenArteconi, Alessiade Andrade Pereira, FláviaHall, MonikaKırant-Mitić, TuğçinCai, HanminJohra, HichamKazmi, HussainLi, RonglingLiu, AaronNespoli, LorenzoSaeed, Muhammad Hafeez2024-01-122024-01-122023-12-010378-7788PURE: 81031477PURE UUID: 8a3f9b0a-b9fc-4cfb-9932-5237148eee1dScopus: 85174333404WOS: 001101041500001http://hdl.handle.net/10362/162213Authors would like to acknowledge the different entities and individuals that supported the research work presented in this article, namely: IEA EBC Annex 82; Giulio Tonellato; the Danish Energy Agency for supporting the Danish delegates participating IEA EBC Annex 82 through EUDP (grant no. 64020-2131); Innovation Fund Denmark in relation to SEM4Cities (no. 0143-0004); EFRE program in relation to the InFlex project (no. 0801826); NeXSyS project under the auspices of Science Foundation Ireland (SFI) (grant no. 21/SPP/3756); the Swiss Federal Office of Energy SFOE (SWEET PATHFNDR grant no. SI/502259-01 and no. SI/50154-01); the Research Foundation – Flanders (FWO) (grant no. 1S66623N and research fellowship no. 1262921N); KU Leuven (C24M/21/021); the Building Technologies Office, Office of Energy Efficiency and Renewable Energy, at the US Department of Energy, under Lawrence Berkeley National Laboratory (contract no. DE-AC02-05CH11231); This work was authored in part by the National Renewable Energy Laboratory, operated by Alliance for Sustainable Energy, LLC, for the U.S. Department of Energy (DOE) under contract no. DE-AC36-08GO28308 with funding provided by U.S. Department of Energy Office of Energy Efficiency and Renewable Energy Building Technologies Office; The views expressed in the article do not necessarily represent the views of the DOE or the U.S. Government. Publisher Copyright: © 2023 The Author(s)This paper examines building energy flexibility at an aggregated level and addresses the main barriers and research gaps for the development of this resource across three design and development phases: market and policy, early planning and design, and operation. We review methodologies and tools and discuss barriers, challenges, and opportunities, incorporating policy, economic, technical, professional, and social perspectives. Although various legal and regulatory frameworks exist to foster the development of energy flexibility for small buildings, financing mechanisms are limited with a significant number of perceived risks undermining private investment. For the early planning and design phase, planners and designers lack appropriate tools and face interoperability challenges, which often results in insufficient consideration of demand response programs. The review of the operational phase highlighted the socio-technical challenges related to both the complexity of deployment and communication, as well as privacy and acceptability issues. Finally, the paper proposes a number of targeted research directions to address challenges and promote greater energy flexibility deployments, including capturing building demand side dynamics, improving baseline estimations and developing seamless connectivity between buildings and districts.213686105engClustersDesignDistrictsEnergy CommunitiesEnergy flexibilityOperationPlanningCivil and Structural EngineeringBuilding and ConstructionMechanical EngineeringElectrical and Electronic Engineeringreview10.1016/j.enbuild.2023.113608https://www.scopus.com/pages/publications/85174333404