The BUILD UP initiative was established by the European Commission in 2009 to support EU Member States in implementing the Energy Performance of Buildings Directive (EPBD). The BUILD UP web portal is intended to reap the benefits of Europe's collective intelligence on energy reduction in buildings for all relevant audiences. It brings together new practitioners and professional associations while motivating them to exchange best working practices and knowledge and to transfer tools and resources. The BUILD web portal targets professionals working in the building sector (public or private) with an interest on the latest developments at technical or practice level, policy legislation, financial issues, etc. http://www.buildup.eu/en/news/create-compact-retrofit-advanced-thermal-energy-storage-0