Abstract The movement toward the 4th generation district heating (4GDH) embraces a great opportunity to support the future smart energy development concept. However, its development calls for addressing technological and economic obstacles aligning with the need for a reformation of the energy market to ensure the quality of service. In this context, our paper presents a comprehensive analysis based on a multi-objective optimization framework incorporating an artificial neural network-based model for the possibility of integrating heat pump (HP) into solar assisted district heating system (SDHS) with seasonal thermal energy storage to support the sustainable transition toward 4GDH. The study evaluates the performance of the proposed system with the help of key performance indicators (KPI) related to the 4GDH characteristics and key stakeholders for possible market growth with consideration for the environmental benefits. The proposed analysis is applied to a small neighbourhood of 10 residential buildings located in Madrid (Spain) to investigate the optimal integration of HP under different control strategies into a SDHS. Inherent the SDHS operator perspective, the results reveal a significant improvement in the stabilization of the SDHS performance due to the HP integration where the solar field temperature never exceeds 80 °C, and the seasonal storage tank (SST) temperature stands at 85.4 °C. In addition, the share of solar energy stands above 86.1% with an efficiency of 73.9% for the SST, while the seasonal HP performance factor stands above 5.5 for all optimal scenarios. From the investor viewpoint, an energy price of 59.1 Euro/MWh can be achieved for the proposed system with a payback period of 26 years. Finally, from the policymaker perspective, along with the significant economic and sustainable improvement in the SDHS performance, a substantial environmental improvement of 82.5% is achieved when compared to the conventional boiler heating system. The proposed analysis reflects a great motivation for different stakeholders to propose this system as a path toward the 4GDH in the future district energy systems.

中文翻译：

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灵活的热泵集成以促进向第四代区域供热的可持续过渡

摘要 向第四代区域供热（4GDH）发展的运动迎来了支持未来智慧能源发展理念的绝佳机会。然而，它的发展需要解决技术和经济障碍，以满足能源市场改革以确保服务质量的需要。在这种情况下，我们的论文提出了基于多目标优化框架的综合分析，该框架结合了基于人工神经网络的模型，用于将热泵 (HP) 集成到具有季节性热能存储的太阳能辅助区域供热系统 (SDHS) 中的可能性支持向 4GDH 的可持续过渡。该研究借助与 4GDH 特征和关键利益相关者相关的关键绩效指标 (KPI) 评估拟议系统的绩效，以考虑环境效益，以实现可能的市场增长。建议的分析应用于位于马德里（西班牙）的 10 座住宅建筑的小社区，以研究在不同控制策略下 HP 与 SDHS 的最佳集成。从 SDHS 运营商的固有角度来看，结果表明，由于 HP 集成，SDHS 性能的稳定性有了显着改善，其中太阳能场温度从未超过 80 °C，季节性储罐 (SST) 温度为 85.4 °C。此外，太阳能的份额超过 86.1%，SST 的效率为 73.9%，而季节性 HP 性能系数在所有最佳方案中都高于 5.5。从投资者的角度来看，拟议系统的能源价格为 59.1 欧元/兆瓦时，投资回收期为 26 年。最后，从政策制定者的角度来看，随着 SDHS 性能的显着经济和可持续改进，与传统锅炉加热系统相比，实现了 82.5% 的显着环境改善。拟议的分析反映了不同利益相关者提出该系统作为未来区域能源系统中通往 4GDH 的道路的巨大动机。从决策者的角度来看，随着 SDHS 性能的显着经济和可持续改进，与传统锅炉供暖系统相比，实现了 82.5% 的显着环境改善。拟议的分析反映了不同利益相关者提出该系统作为未来区域能源系统中通往 4GDH 的道路的巨大动机。从决策者的角度来看，随着 SDHS 性能的显着经济和可持续改进，与传统锅炉供暖系统相比，实现了 82.5% 的显着环境改善。拟议的分析反映了不同利益相关者提出该系统作为未来区域能源系统中通往 4GDH 的道路的巨大动机。