# Exploring the Benefits and Limitations of Digital Twin Technology in Building Energy
## 5 Digital Twin Technology for Energy Sector Development
### Software for Energy Prediction-Actual Software Cases
The use of BIM and 3D laser scanning technology can be used to effectively evaluate retrofit options for existing buildings with almost zero energy consumption and to improve energy efficiency by adjusting the angle of the solar PV modules. The discussion pointed out that while China is making progress in new almost-zero-energy buildings, a more comprehensive assessment strategy is still needed for the almost-zero-energy retrofitting of existing buildings. In some of the newer studies, EnergyPlus is being used in conjunction with programming software to perform energy simulations and forecasts. When EnergyPlus is used as a core tool for building energy modelling, the decision-making tools that accompany it can greatly enhance energy analysis and optimization capabilities. Such decision tools can include multi-criteria decision analysis tools, life cycle cost analysis tools and machine learning tools. Areas of relevance to the use of EnergyPlus simulation results with multi-criteria decision analysis tools to evaluate building energy strategies include [PERSON] et al. [81]'s energy simulation of an office building in north-western Italy with decision tools to support investment in intelligent shading devices for the office building. The article uses EnergyPlus as an energy dynamic simulation tool and Visual PROMETHEE as a multi-criteria decision analysis tool for building modelling BIM and energy analysis. The results show that external blinds in combination with control strategies can reduce indoor air conditioning demand. The use of control strategies can have a positive impact on buildings in terms of energy savings, environmental impact, thermal comfort and visual comfort. [PERSON] et al. [83] compared the impact of photovoltaic electrochromic windows on the building lighting environment and energy savings in Chengdu, China when combined with different control strategies. The study methodology consisted mainly of constructing a test setup for zoned PV electrochromic windows with different control strategies using Energy Plus to simulate the building's interior lighting environment and energy performance. The results show that different control strategies can reduce indoor building energy consumption in specific application scenarios. In future research, we will integrate four control strategies for different types of buildings at specific times to achieve an optimal combination of control strategies considering the indoor lighting environment and building energy consumption. [PERSON] et al. [110] modelled the dynamics of operational energy use in a life cycle assessment (LCA) of a Belgian office building. The building is a commercial office building. The dynamic modelling approach developed in this paper uses EnergyPlus software to combine dynamic energy use in the operational phase with natural gas and electricity scenarios, in conjunction with climate data for the Belgian region. The final environmental cost of electricity increases while the environmental cost of natural gas decreases. Using EnergyPlus simulation results combined with time series or geo-information analysis, predictions are made using historical and real-time simulation data to aid understanding of multiple building energy use patterns, advance predictions of likely energy demand, and more accurate energy strategy decisions. This area includes a study by [PERSON] et al. [73] of how the interaction between ten typical buildings located in a high-density urban area of Hong Kong affects the energy consumption of buildings.. The inter-building effect (IBE) of building energy consumption in a high-density urban office environment in Hong Kong was analyzed using EnergyPlus. GIS (Geographic Information Systems) was used to create and analyze models of buildings and their surroundings, and the completed geometric models were exported to EnergyPlus for dynamic building energy simulation.