Advanced Energy Systems in Energy-Resilient and Zero/Positive Energy Buildings, Communities, and Districts

The pursuit of sustainable energy solutions has become a critical focus in addressing the challenges of climate change and urbanization. This Special Issue provides a comprehensive overview of recent research in the field of energy and sustainability, encompassing diverse topics such as urban energy planning, short-term electrical load forecasting, energy resilience, energy flexibility, energy efficiency, nearly zero-energy buildings and districts, and the development of Positive Energy Districts (PEDs). The studies included in this Special Issue demonstrate the importance of combining innovative technologies, community engagement, and policy support to achieve energy efficiency and sustainability goals. By exploring the practical applications and impacts of these advancements, this Special Issue fosters a holistic understanding of the current state of energy research and its potential to drive positive change in urban environments. This Special Issue includes a total of 16 papers covering different aspects of building and district planning, technologies and their economics, building design and retrofitting, citizen engagement and the collection of energy data, energy resilience, and energy flexibility.

Multiple studies discuss the development and benefits of Positive Energy Districts (PEDs), which aim to achieve net-zero energy imports and CO₂ emissions while producing surplus renewable energy [1]. PEDs, defined as urban areas that produce more renewable energy than they consume, are explored through various case studies [2]. This Special Issue highlights the importance of building renovations, renewable energy integration, and community engagement in achieving sustainable urban development. PEDs have the potential to support energy accessibility, alleviate energy poverty, and contribute to carbon reduction [3]. Key sustainable development goals can be achieved through PEDs, such as energy accessibility, sustainable cities, and climate action [4]. Different methodologies to evaluate the multiple benefits of PEDs are developed with the use of stakeholder engagement to align project strategies with broader perspectives [5]. The advancements in energy and sustainability research presented in this Special Issue underscore the critical role of innovative technologies, predictive modeling, and community engagement in achieving sustainable urban development. The integration of automated data collection, energy demand prediction, and renewable energy sources into urban energy planning and retrofitting frameworks has demonstrated significant potential in reducing energy consumption and emissions and enhancing efficiency. Positive Energy Districts (PEDs) have emerged as a promising solution to urban sustainability challenges, offering benefits such as energy self-sufficiency, energy resilience, energy flexibility, reduced carbon emissions, and improved social equity and energy resilience [6]. Therefore, future cities and districts require planning that can accommodate such innovative districts and buildings based on local conditions in order to provide carbon-neutral, sustainable, and resilient districts that are socially acceptable and economically feasible.

Evaluations of green building technologies and post-evaluation studies underscore the need for continuous improvement in energy efficiency and occupant satisfaction [7]. While green buildings generally meet energy performance standards, the effectiveness of certain technologies, particularly energy-saving ones, can be improved. Research on novel technologies such as wireless power transfer for battery-charging smart controls, glazing, and the reuse of advanced building materials demonstrates their potential to contribute to sustainability. In addition, producing energy through waste (using heat recovery) is another method that can support sustainability goals [8]. Hence, further research is needed to introduce these innovative solutions to society in a way that is economical, scalable, and can be replicated.

The benefits of district-level energy strategies over individual building retrofits are highlighted in this Special Issue, including significant reductions in CO₂ emissions and energy use. Effective stakeholder engagement can lead to new, more effective solutions; however, new methods are needed to achieve this [9] in order to provide feasible solutions. Advances in machine learning and data analysis are highlighted for improving the accuracy of energy demand predictions [10]. Various machine learning models for short-term load forecasting in buildings are discussed, with the most accurate methods identified based on different data resolutions and time steps. The Special Issue highlights the importance of data preparation in model accuracy, error calculations, forecasting, and performance analysis [10].

This Special Issue highlights the importance of energy-efficient technologies, renewable integration, the circular economy, and advanced data-driven prediction models in creating sustainable and resilient urban environments. From Positive Energy Districts (PEDs) to waste heat recovery and building retrofitting, these approaches are paving the way for the achievement of net-zero and positive energy goals. Technologies such as machine learning and energy simulation tools can enhance the accuracy of energy predictions and the optimization of resources.

We would like to thank the authors of the papers for their valuable contributions to this Special Issue. We also wish to express our gratitude to the reviewers of the papers for their time and effort.