# Autonomous Cyber-Physical Systems Enabling Smart Positive Energy Districts
## 1 Introduction
Nowadays, urban development is advancing from individualized building solutions to whole-district solutions [20] or Energy Communities (ECs) [21]. These solutions were introduced in 2019 in EU legislation. The aim of ECs was to empower citizens to propel the energy transition locally so that they could benefit from the advantages, such as improved energy efficiency, lessened energy poverty, reduced energy bills, and the potential for local green jobs [9]. The thought behind ECs was to improve public acceptance of renewable energy approaches and to attract private investment. A political objective of achieving one EC by 2025 per municipality with a population of higher than 10,000 was proposed [22]. The ECs are significantly correlated with PEDs. The transactive energy market aims to enhance power systems' efficiency, robustness, and reliability by working towards a more intelligent and interactive future for the energy industry. Industry 4.0 technologies, comprising CPSs, Digital Twins (DTs), and the Internet of Things (IoT), are being used to introduce intelligence in the manufacturing industry [23]. Additionally, the Industry 4.0 paradigm is based on four strategic principles related to CPSs, as follows [24]:  
1. _Interconnectivity_: devices, machines, sensors, and humans communicate among themselves through the IoT;
2. _Technological Assistance_: the technological systems support humans in monitoring, problem-solving, and decision-making;
3. _Information Transparency_: operators receive detailed information that is critical for decision-making;
4. _Decentralized Decision-Making_: CPSs take decisions and perform tasks independently and automatically. The concept of Construction 4.0, a term used for making use of digital advancements in the construction industry, employs similar principles to Industry 4.0 [25]. In Construction 4.0, data-driven systems are utilized for management of physical processes and for the decentralization of processes associated with decision-making [25]. The emphasis of this study is on the role of CPSs in PEDs. CPSs are traditionally leveraged in large-scale industrial and autonomous domains [26]. However, with recent technological developments, new application domains are available for CPSs, including applications for smart grids, electric vehicles, PEDs, etc. A significant research gap in the context of CPSs within PEDs lies in the absence of a comprehensive approach to assessing and modeling the complex interactions between physical components on one hand and cyber components on the other hand. The potential of CPSs to optimize energy management and enhance PED sustainability is recognized. However, description and examples of their practical implementation, particularly in the context of urban energy systems, is scarce in the literature. This entails a need for detailed description of CPS architectures tailored to PEDs, and strategies for integrating CPSs into existing infrastructures, ensuring compatibility and interoperability between new and legacy systems. The interplay between buildings, infrastructure, and user behavior needs to be taken into consideration, together with integration of heating, cooling, electricity, etc. Engaging stakeholders, such as citizens, policymakers, and energy providers in the design and implementation of CPSs is a significant challenge. Lately, a more interdisciplinary approach, including a connection between human factors and the CPS domains, has been identified and is called _\"human-in-the-loop CPS (HiLPS)\"_[27]. Nevertheless, current research usually focuses on specific aspects of CPSs in PEDs, such as energy management and cybersecurity. A holistic approach is needed to integrate knowhow and experience from different fields, including computer science, energy engineering, urban planning, and social sciences. The aim of this study is to examine the role of contemporary emerging technologies, including CPSs, DTs, AI, IoT, edge computing, and blockchain, in the creation, advancement, and operation of PEDs.