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Reducing energy use within the building sector is vital to create sustainable cities and mitigate global warming. Urban building energy modelling (UBEM) is useful to evaluate energy demand and renovation potential in districts. In this paper, an archetypes-based calibration approach for UBEM is introduced to evaluate the effect of various timescales for energy data and detail of building-related data on the energy performance of multi-residential buildings. A case district in northern Sweden was used to identify the impact of various refurbishment strategies at district-scale.

The applicability of the archetypes-based calibration approach was validated by comparing the district model performance with high-resolution energy data. Calibrating the archetypes-based model with monthly resolution data showed a similar outcome as using higher-resolution data. Further, a district model with less archetypes can reduce modelling time and complexity, while performing similarly as a model consisting of more archetypes with higher detail. The results suggest that simplifications to UBEM can be used without compromising the performance accuracy and might facilitate district modelling in situations with data limitations.

The findings in this study contribute to the knowledge on UBEM of existing districts and energy efficiency measures’ impact on district-level energy performance.

In 2018, EU launched the programme “Positive energy districts and neighbourhoods for sustainable urban development” with an aim to support the planning, deployment and replication of 100 Positive energy districts (PEDs) by 2025. This is an ambitious target considering the various challenges on implementing PEDs. This paper, based on literature review, provides an overview on the challenges and possibilities on the three main components of PEDs; energy production, energy efficiency and energy flexibility.

Positive energy district (PED) is a novel idea aimed to have an annual surplus of renewable energy and net zero greenhouse gas emissions within an area. However, it is still an ambiguous concept, which might be due to the complexity of city district projects with interconnected infrastructures and numerous stakeholders involved. This study discusses various aspects of PED implementation and presents practitioners’ experiences with the PED concept, challenges, and facilitators they have faced with real projects. The study is based on interviews with ten Swedish professionals. The major challenges reported for PED implementation were local energy production and energy flexibility, sub-optimization, legislation, suitable system boundaries, and involvement of stakeholders. Most of the interviewees mentioned improved collaboration, integrated innovative technology, political support, and climate change mitigation goals as important facilitators. The interviewees highlighted the importance of a local perspective and considered each city’s preconditions when developing a PED project. The study emphasizes that to facilitate PED implementation and replication in cities, more knowledge and clarity is required about PED such as on the definition and system boundaries.

Positive energy districts (PED) are neighborhoods with a net positive energy balance with the main goal to create sustainable districts that contribute to the energy transition. The three pillars energy efficiency, renewable energy, and energy flexibility forms the foundation of PEDs, and ‘Quality of life’ is one of the key principles.

Indoor swimming facilities for recreation and sports, also called aquatic centers or swimming halls, are important for healthy lifestyles. They are highly energy-demanding facilities due to the large volumes and strict heating- and ventilation requirements to ensure the health of staff, visitors, and bathers. The large energy consumption indicates good potential to reduce their energy use. One possibility might be to include aquatic centersin PEDs: the district could support the facility with locally produced renewable energy. There are also studies that investigates innovative solutions regarding aquatic centers that might have potential to increase resilience and flexibility in the district.

However, one important aspect in studies on energy use in aquatic centers that is often neglected is the presence of disinfection by-products (DBP), which are found in the air and water of chlorinated swimming pools. Several DBPs can lead to health issues, such as asthma, eye irritation, and even cancer. There are often conflicting goals in studies on swimming halls. The connection between DBP and energy is currently missing, and it could lead to projects compromising health over energy savings. Based on a literature review, this study highlights the research gap between DBPs and energy use in swimming facilities. A suggestion is also presented to integrate swimming halls into PEDs with the aim of increasing possibilities for a healthy lifestyle, supporting the aquatic center’s energy demand with renewable energy, and exploring new solutions for flexibility and resilience in the district

A Positive Energy District (PED) is an inclusive, energy efficient district with optimized energy flows and a local production of renewable energy, with an annual surplus of energy that can be exported to other areas. Most of the municipalities in Sweden have ambitious climate neutrality goals and implementing PEDs in cities could be one way to contribute to the achievement of those climate goals. However, PED is an innovative concept which is still ambiguous for many stakeholders, and many uncertainties remain. To understand the perspectives of Swedish stakeholders towards PEDs, a three hour long online workshop was organized in December 2020. Representatives from city officials, universities, energy utilities and real estate companies participated in the discussion groups. The groups discussed three topics related to PED, namely; 1) Definition of PED, 2) Challenges and drivers for PEDs and 3) Replication of PEDs.

Most of the discussion groups agreed to the importance of viewing PEDs as a part of the larger energy system and to find holistic solutions and promoting collaboration between actors. Most groups considered leadership and stakeholder engagement as important drivers for PEDs. Further, participants discussed that the slow decision processes in municipalities could be a challenge for PEDs. Even though there was consensus on most challenges and drivers, one aspect where participants had conflicting opinions was the PED definition. Some groups thought that the PED definition needs to be clearer and more narrow, while others saw it as a potential barrier if it becomes too technology focused. During discussions on replication, most groups stressed the importance of knowledge sharing and the results highlight that different stakeholders can play different roles in facilitating replication for PEDs. The study highlights the importance of a regional perspective when developing the PED definition, since the Swedish stakeholders had different viewpoints on PED that could be used to adapt the definition.