Integrating thermal energy storage with building energy systems can enable flexible building electric demands at buildings to help mitigate the mismatch between electricity supply and demand. A novel building heating and cooling system that integrates a dual-source heat pump with hybrid thermal storage named dual-purpose underground thermal battery (DPUTB) has been developed for reshaping building electric demands. The proposed DPUTB integrated geothermal heat pump system is an original innovation that enables Grid-interactive Energy Efficient buildings. This paper focuses on the study of the novel DPUTB. The DPUTB works as both a thermal storage tank (an inner tank) and a ground heat exchanger (an outer tank separated from the inner tank by the insulation material). High fidelity and computationally effective models are needed to predict the performance of the novel DPUTB. This study has developed a simplified dynamic model for the DPUTB according to heat transfer and energy conservation principles and validated it by using experimental data obtained from testing a small-scale DPUTB apparatus. A parametric study was conducted to identify a design that can achieve the target thermal storage performance of load shift and energy efficiency. The parametric study results show that the inner tank shell thermal conductivity and the phase change material's melting point are the two most influencing factors on the performance of the DPUTB. One single full-size DPUTB with the identified design could provide 1-ton cooling (3.51 kW) with the supply temperature lower than 11 °C for 4 hours in summer after being fully charged in 8 hours. The inner tank filled with phase change material is for cooling thermal storage as a latent tank in the design. However, its capacity can be as high as 60 MJ as a sensible water tank for heating storage in winter. In the future study, the DPUTB model will be incorporated into the dual-source heat pump system for evaluating the overall system performance of demand side management in the long term.

将热能储存与建筑能源系统集成可以实现灵活的建筑电力需求，以帮助缓解电力供需之间的不匹配。为了重塑建筑用电需求，已经开发出一种将双源热泵与混合蓄热器集成在一起的新型建筑供暖和制冷系统，名为双用途地下热电池 (DPUTB)。拟议的 DPUTB 集成地热热泵系统是一项原创性创新，可实现电网互动式节能建筑。本文重点研究小说DPUTB。DPUTB 既可用作储热罐（内罐），也可用作地面热交换器（外罐与内罐通过绝缘材料隔开）。需要高保真度和计算有效的模型来预测新型 DPUTB 的性能。本研究根据传热和节能原理开发了 DPUTB 的简化动力学模型，并通过测试小型 DPUTB 装置获得的实验数据对其进行了验证。进行了一项参数研究，以确定可以实现负载转移和能源效率的目标蓄热性能的设计。参数研究结果表明，内胆壳热导率和相变材料的熔点是影响DPUTB性能的两个最大因素。一个具有确定设计的全尺寸 DPUTB 可以提供 1 吨冷却（3. 51 kW），8 小时充满后，夏季供电温度低于 11 °C 4 小时。填充相变材料的内胆用于冷却蓄热，作为设计中的潜池。但是，它的容量可以高达60兆焦耳，作为冬季储热的显水箱。在未来的研究中，DPUTB模型将被纳入双源热泵系统，用于长期评估需求侧管理的整体系统性能。