Semantic digital twinning has traditionally supported design coordination, documentation, and planning during the early stages of building projects. However, its application in building operation and maintenance—particularly in real time—remains limited. This study proposes a methodology for cost-optimal HVAC load management using an operational digital twin, and demonstrates its real-time application under a residential time-of-use pricing scheme. The framework is implemented in a grid-connected single-family house equipped with smart thermostats, rooftop photovoltaic panels, and battery storage, and is evaluated under two progressive layers of control and system integration: predictive thermostat control alone, and combined coordination of thermostats, on-site generation, and battery systems. Each configuration is assessed against a static reference derived from two baseline weeks without energy flexibility. Results show that predictive thermostat control reduced electricity costs by an average of 34.7 %, with a total increase in energy import of approximately 84 kWh, while maintaining average indoor temperature deviations below 0.3 °C. Coordinated control achieved 78.4 % average cost savings, reduced net grid import by 115 kWh, and enabled 25.3 kWh of energy export. Relative demand shift analysis confirmed effective load advancement and midday demand reduction, delivering both economic and grid-responsive outcomes. These findings highlight the feasibility of deploying real-time predictive control in operational residential buildings to enhance load flexibility and improve alignment with dynamic electricity pricing.

中文翻译：

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用于成本最佳 HVAC 运行的语义数字孪生：在分时电价下实时应用于带有智能恒温器和 PV/电池的房屋

语义数字孪生传统上支持建筑项目早期阶段的设计协调、文档编制和规划。然而，它在建筑运营和维护中的应用（尤其是实时应用）仍然有限。本研究提出了一种使用运营数字孪生进行成本最优的 HVAC 负载管理的方法，并展示了其在住宅使用时间定价方案下的实时应用。该框架在配备智能恒温器、屋顶光伏板和电池存储的并网单户住宅中实施，并在两个渐进的控制和系统集成层下进行评估：单独的预测性恒温器控制，以及恒温器、现场发电和电池系统的组合协调。每个配置都根据从没有能源灵活性的两周基线周得出的静态参考进行评估。结果表明，预测性恒温器控制平均降低了 34.7% 的电力成本，能源进口总量增加了约 84 kWh，同时将平均室内温度偏差保持在 0.3 °C 以下。 协调控制实现了 78.4% 的平均成本节约，将电网净进口量减少了 115 kWh，并实现了 25.3 kWh 的能源出口。相对需求转移分析证实了有效的负荷提前和午间需求减少，实现了经济和电网响应的结果。这些发现强调了在运营住宅建筑中部署实时预测控制以提高负载灵活性并改善与动态电价的一致性的可行性。