(1) Background: To support the energy transition in Europe, the EU has launched multiple initiatives. Supporting the “Green Deal” is the New European Bauhaus (NEB). District heating and cooling (DHC) is an important part of a decarbonized European energy system, and its role in the transition has been stressed by the EU. In this paper, DHC is, for the first time, reviewed assuming the NEB principles. (2) Method: a literature review combined with a review of three cases was used for collecting data. (3) Results: It is confirmed that DHC has strong sustainability values. It is also identified that DHC can become increasingly inclusive by adopting updated digital platforms and new technologies for heat recovery that necessitate close customer interaction whilst recovering waste heat. The least exploited principle is aesthetics. It could sharpen city planning by combining energy system and energy efficiency perspectives, increase the practice of multifunctional buildings (for example energy provision and recreation), and foster a closer interplay between architecture and energy. (4) Conclusions: for both innovating and expanding DHC, the NEB principles can serve as catalysts.

Renewable Energy Communities (REC) are an emerging initiative that aims to contribute to the energy transition towards a more decentralised system in Europe by encouraging local communities to come together and invest in and operate renewable energy assets together. Decision-making processes of these communities need to be supported by adequate tools, which also can be used in the formation of the community groups in the first place. In this paper a case-study of four European small-town communities in Berchidda (Italy), Ollersdorf (Austria), Ispaster (Spain), and Kökar (Finland) carried out in the context of the LocalRES project is presented, where a participatory design methodology has been applied to co-create community supporting tools. Feedback gathered during four citizen workshops is presented, showing that to optimally support RECs in their formation and operation three main topics need to be supported: (1) the technical realisation and potential upgrades of the energy system, i.e., visualising energy generation and consumption on an individual and a community level, (2) the financial and economic implications of investments, i.e., calculating costs and return on investment for the individual and for the community, as well as (3) the social dimension and communication between community members and other relevant stakeholders, i.e., helping with community building and community engagement. The participatory process presented in the case studies does not only serve to gather requirements for tool design, but it also is a useful vehicle to bring together all interested citizens and understand their needs and concerns. A summary of this detailed citizen feedback is also presented.

The development of integrated renewable energy and high-density thermal energy storage systems has been fueled by the need for environmentally friendly heating and cooling in buildings. In this paper, MiniStor, a hybrid thermochemical and phase-change material storage system, is presented. It is equipped with a heat pump, advanced electronics-enabled control, photovoltaic–thermal panels, and flat-plate solar collectors. To optimize energy flows, regulate charging and discharging cycles, and maintain operational stability under fluctuating solar irradiance and building loads, the system utilizes state-of-the-art power electronics, variable-frequency drives and modular multi-level converters. The hybrid storage is safely, reliably, and efficiently integrated with building HVAC requirements owing to a multi-layer control architecture that is implemented via Internet of Things and SCADA platforms that allow for real-time monitoring, predictive operation, and fault detection. Data from the MiniStor prototype demonstrate effective thermal–electrical coordination, controlled energy consumption, and high responsiveness to dynamic environmental and demand conditions. The findings highlight the vital role that digital control, modern electronics, and Internet of Things-enabled supervision play in connecting small, high-density thermal storage and renewable energy generation. This strategy demonstrates the promise of electronics-driven integration for next-generation renewable energy solutions and provides a scalable route toward intelligent, robust, and effective building energy systems.

Objective: Older age and cardiovascular comorbidities are well-known risk factors for all-cause mortality in COVID-19 patients. Hypertension (HT) and age are the two principal determinants of arterial stiffness (AS). The objective of this study is to estimate AS in COVID-19 patients requiring hospital admission and analyze its association with all-cause mortality. Design and method: This cross-sectional, observational, retrospective multicenter study includes 122170 patients who required hospital admission in 150 Spanish centers, included in the nationwide SEMI-COVID-19 Network. We compared estimated AS as pulse pressure > 60 mmHg and compared clinical characteristics between survivors and nonsurvivors. Results: Mean age was 67.5 ± 16.1 years, 42.5% were women. Most patients were white (90.0%). Globally, 2606 (21.4%) subjects died. Blood pressure (BP) < 120 mmHg and BP > 140 at admission predicted higher all-cause mortality (23.5% and 22.8%, respectively, p < 0.001), compared to BP between 120–140 mmHg (18.6%). 4379 patients with AS (36.0%) were older and had higher systolic and lower diastolic BP. Multivariate analysis showed that even adjusting for gender (males, OR: 1.6, p = 0.0001), age tertiles (second and third tertiles, OR: 2.0 and 4.7, p = 0.0001), Charlson-Index (second and third tertiles, OR: 4.8 and 8.6, p = 0.0001), heart failure, previous and in-hospital antihypertensive treatment, AS and BP < 120 mmHg significantly and independently predicted all-cause mortality (OR: 1.27, p = 0.0001 and OR: 1.48, p = 0.0001, respectively). Conclusions: Our data show that arterial stiffness, defined as pulse pressure above 60 mmHg at hospital admission, and BP at admission < 120 mmHg were important determinants with independent prognostic value for all-cause mortality in COVID-19 patients requiring hospitalization.

Decarbonisation of urban areas is essential to reaching climate neutrality, as cities house half the global population and account for over 70% of carbon emissions. However, applying innovative approaches, such as establishing positive energy districts (PEDs), remains challenging due to stakeholder engagement and funding constraints, largely driven by knowledge gaps and a lack of best practices. This study examines barriers, facilitators and lessons learnt from six case studies in Europe, Canada and Singapore through a mixed-methods approach, including stakeholder interviews, grey literature analysis and a semi-structured review. Findings highlight district heating networks, heat pumps and photovoltaics as key technologies, with regional variations. While Mediterranean regions prioritise solar energy, northern climates employ a diverse range of solutions, including geothermal and seasonal storage. Political commitment and funding enable progress, whereas regulatory gaps and stakeholder misalignment hinder it. The study underscores the need for sharing best practices to enable PED implementation.