Nearly Zero Energy Buildings (nZEBs) represent the backbone to achieve ambitious European goals in terms of energy efficiency and CO2 emissions reduction. As defined in the EPBD, by 31 December 2020, all of the new buildings will have to reach a target of nearly zero energy. This target encourages the adoption of innovative business models as well as the technology development in the building sector, aimed at reducing energy demand and exploiting local renewable energy sources (RES). Assessing the share of implementation and the performance of technologies in new or renovated nZEBs is strategic to identify the market trends and to define design guidelines with the most effective solutions according to the context. In this regard, this paper analyses the construction features of a set of nZEBs, collected in 17 European countries within the EU IEE ZEBRA2020 project, with a special focus on the influence of the boundary conditions on the technologies adopted. The results show a general high insulation level of the envelope and recurrent specific technologies in the Heating Ventilation Air Conditioning (HVAC) system (i.e., heat pumps and mechanical ventilation), while the climatic conditions do not drive significantly the design approach and the nZEB features.

Energy efficiency in the building sector plays a key role in supporting European and global commitments against the current climate crisis. A massive adoption of deep renovation measures would allow a global reduction of energy need up to 36%, based on estimations. However, the market for building renovation is still limited, due to uncertainties associated with risk evaluation. This paper aims to suggest a method to evaluate the financial impacts of technical risks related to energy efficiency investments. Key performance indicators (KPIs) necessary to evaluate the investment risk associated with energy renovation have been defined based on an analysis of the correlation between technical and financial risks, and their originating factors or root causes. The evaluation has been carried out thanks to the EEnvest tool: a web-based search and match platform, developed within the EEnvest collaborative research project funded by the European Commission (EC). This evaluation methodology has then been applied to a case study, an office building located in Rome, for whom an energy efficient renovation project was already in place to reduce energy needs. The investment risk of the renovation project is calculated for two different scenarios: with and without risk mitigation measures being applied during the design, installation and operation phases. The results show the different technical and financial risk trends of these two scenarios, highlighting the benefits obtained by the implementation of mitigation measures.

Energy efficiency in the building sector is a priority of the EU Commission to achieve carbon neutrality by 2050. Renovation of the existing buildings, which are currently responsible for approximately 40% of EU energy consumption and 36% of the greenhouse gas emissions can lead to significant energy savings. This paper presents the EEnvest calculation method for evaluating the financial impacts of technical risks related to energy-efficient renovation of commercial office buildings. The evaluation method aims to increase investors’ confidence and boost investments in the renovation of the existing building. Through a series of Key Performance Indicators (KPI), the technical and financial risks impact is evaluated. The results are strictly connected to building features, climatic conditions, solution sets and mitigation measures specific to the building energy efficiency project.

The European Union aims to achieve climate neutrality by 2050, prioritizing energy efficiency particularly in the building sector. Despite significant policies, such as the EU Green Deal and Renovation Wave initiative, the rate of deep energy renovations remains insufficient, with only 0.2% annually versus the 3% required. Multiple barriers hinder the progress of deep energy renovations (DERs), including fragmentation among stakeholders, the limited coordination of RDI (Research, Development, and Innovation) efforts, and a lack of systemic approaches. The objective of this paper is to illustrate a holistic methodological approach for enhancing the DER market uptake based on transition pathways theory (TPT) and is designed to drive structural evolution in DER markets aimed at overcoming their main current constraints. To this end, five key transition pathways are outlined—namely institutionalization, clusterization, capitalization, digitalization, and exploitation—and are conceived for fostering coordination, integration, promotion, and efficient scaling of innovations along the whole DER value chain. This approach was tested in seven EU building market ecosystems under the H2020 re-MODULEES project, aimed at developing a market activation platform conceived as a digital enabler for next-generation One-Stop Shops (OSSs). This project yielded practical evidence on the potentiality of the TPT frame to strengthen and empower local ecosystems through stakeholders’ engagement and cooperation. The findings suggest that the TPT-based approach tested in re-MODULEES can effectively address structural challenges in diverse DER renovation markets, and for this reason, it may be also tested and extended in other ecosystems across Europe in order to be validated as a strategic approach at the EU level for facilitating the transition to low-carbon buildings.

The goal of the interdisciplinary study presented in this paper was to identify opportunities for innovative applications of mycelium in construction, including housing construction. This solution is gaining significance due to its sustainability and eco-friendliness. Mycelium can be seen as an innovative alternative to traditional building materials, and can be transformed into permanent structures using mycotecture. In 2023, within the framework of cooperation between researchers from the Warsaw University of Technology and experts from the Łukasiewicz Research Network Institute, an experimental study was conducted and produced interesting results. The study is at the testing stage. The interdisciplinary research team grew to include researchers from the Cracow University of Technology, Eurac Research from Italy and InnoRenew CoE from Slovenia. The methodology of research on mycotecture is a comprehensive process that begins with defining research goals and analyzing the literature. After analyzing existing cases and drawing conclusions, research experiments are designed, which include both laboratory tests and field tests. Field tests of the material produced during the study was linked with the participation of students from the Warsaw University of Technology, who built the Future Pavilion also known as the “We Stand For” initiative, where a prototype mycelium brick was used in the pavilion’s structure.