# Exploring the Benefits and Limitations of Digital Twin Technology in Building Energy
## 1 Introduction
### Definition and Development History of Digital Twin  
Digital twin technology connects a physical entity with its virtual model in real-time, thanks to its comprehensive and sophisticated capabilities. Using this technology, various functions can be realized, including simulation, integration, testing, monitoring, and maintenance. Using accurate and detailed virtual models, they monitor device status, predict their future behavior, and even explore a wide range of operational strategies. This allows for a deeper understanding of real-world systems and optimization. Digital twin technology was first used by NASA in the Apollo space program in 2002. As a result of these innovations, NASA built replicas and models of the spacecraft systems on the ground (e.g., a digital twin) to efficiently manage and maintain spacecrafts far out in space. This innovation served as the basis for the development of digital twin technology. After [PERSON] of the University of Michigan made a public presentation introducing the idea of the digital twin in 2003 [1]. Since the beginning of the 21 st century, information technology has rapidly developed, especially with the emergence of a new generation of information technologies, including the Internet of Things (IoT), cloud computing, big data analytics, artificial intelligence (AI), and many others. Digitalization has significantly accelerated [2]. As a result of this development, digital twin technology has increasingly been used in various fields. Several fields have been transformed by integrating the physical and virtual worlds, making digitization a driving force of innovation. Various applications of digital twins have been found in areas such as smart cities, healthcare, agriculture, transportation, automotive, aerospace, manufacturing, energy, electricity, and other fields. Manufacturing companies can use digital twins to improve product quality, reduce production costs, increase delivery speed, and predict bottlenecks during the production process to accelerate the launch of new products [3]. An urban planner may use digital twin technology to simulate the infrastructure and operations of a city to provide planning and decision-making advice. Digital twins can be used in the energy sector to simulate and analyze energy demand, for example, to test various lighting designs in various application scenarios through computer simulation to choose the most appropriate one [4]. A digital twin technology in architecture allows real-time connectivity between an actual building and its virtual counterpart. Further to this subject, an effective assessment of unanticipated or unpredictable aspects of a building can be accomplished. Furthermore, it contributes significantly to streamlining building workflows, reducing maintenance costs, improving building user engagement, and integrating a variety of building information technologies into the building operations [5]. Digital twin technology has significantly improved the construction project implementation process, including reducing the time to completion and lowering the budget. Many emerging fields will benefit from this, including the design and construction of smart buildings, where using this technology can reduce the cost and time of building a building, enhance collaboration and productivity, improve the efficiency of utilizing existing buildings, and improve safety and sustainability [6]. In addition, digital twin technology can help achieve some previously unreachable building goals. Additionally, digital twin technology can help meet previously unattainable goals in the construction industry. As an example, this technology can help develop more effective maintenance strategies by providing real-time information on the status of systemsor equipment. The construction industry could achieve this by performing preventive maintenance and improving facility management efficiency.