This report offers an overview of the available technologies for energy renovation and renewable energy supply at the district level. As anticipated, this is the second edition of the Technology Overview Report published in 2020 (and made available on the IEA EBC Annex 75 website since then), completing the set of final reports developed by IEA EBC Annex 75. The first edition was the first of IEA EBC Annex 75 deliverables and documented the work of Subtask A – Technology Overview. It served as a necessary reference for other subtasks, providing helpful information for assessing district renovation examples, especially for the simulations of the case studies and generic districts used in this project to test and verify the developed methodology.@en

This report describes the methodology for identifying and assessing cost-effective strategies for renovating urban districts towards far-reaching objectives regarding reducing carbon emissions and energy use. The report proposes different scenarios considering boundary conditions and different interventions on building envelopes and thermal systems. The proposed methodology builds on the methodology previously developed for individual buildings in IEA EBC Annex 56 (developed by the same main authors of this report), extending it to the level of districts/groups of buildings. Furthermore, it also makes use of results from other related Annexes. The idea is that the methodology supports decision-makers in evaluating the efficiency, impacts, cost-effectiveness and acceptance of various strategies for renovating urban districts, and in identifying suitable renovation strategies. The methodology defines the boundary conditions set for the assessments carried out, the research questions/hypotheses mainly investigated with the assessments, and the type of outputs generated from the assessments. It is intended that, based on the methodology developed, existing tools can be identified, or existing tools can be adapted to support the application of the methodology in case-specific assessments. In addition, an online Calculation Tool (Annex 75 CT) was developed to support the application of this methodology, which is available at: https://annex75.bim.energy and at https://annex75.iea-ebc.org/publications.@en