TY - JOUR
T1 - Validation and optimization of a solar heating plant with a large-scale heat pump
AU - Zhan, Chenxuan
AU - Xu, Yi
AU - Fan, Jianhua
AU - Gao, Meng
AU - Kong, Weiqiang
AU - Wu, Jiani
AU - Wang, Dengjia
AU - Tian, Zhiyong
N1 - Publisher Copyright:
© 2025 The Authors
PY - 2025
Y1 - 2025
N2 - The integration of multi-type heating sources offers immediate advantages at both the component and system levels, addressing thermal and economic considerations effectively. This study developed a dynamic simulation model in TRNSYS for the rum solar district heating plant with an air source heat pump and a gas boiler. The validity of the model was examined in detail using long-term monitoring data of the system. Both component-level validation and loop validation showed the performance of solar collector field, air-source heat pump, and the tank could be closely fit. The simulated system successfully replicated the energy conversion efficiency of the actual system, which was demonstrated with the simulated annual solar collector efficiency, heat pump COP, and the system solar fraction with error kept below 5%. Moreover, the control strategy employed in the simulation prioritized heat pump operation within a demand-response framework, thereby reducing reliance on the boiler and resulting in a system-levelized cost of heat of 62.2 EUR/MWh, compared to 68.6 EUR/MWh in the actual system. Based on the simulated system. parameter study indicates the capital cost is sensitive to solar collectors and heat pump. GenOpt and TRNSYS are employed to minimize the solar loop's net-levelized cost of heat with the aim of upscaling the heating plant. Considering the geographical constraints, maximizing collector area and tank volume can increase solar fraction by 20% and reduce sLCOH by 0.9 EUR/MWh, as shown with an 8000 m3 tank and 12,605 m3 of solar collectors. Besides, increasing the heat pump heating capacity to 3.4 MW is recommended because the system-levelized cost of heat can be further decreased by 1.1 EUR/MWh, and the CO2 emission could be decreased by 12%. The findings of the paper present a good reference for consultants and engineers in their efforts to develop solar heating systems with enhanced thermal performance along with low system-levelized costs of heat and carbon emissions.
AB - The integration of multi-type heating sources offers immediate advantages at both the component and system levels, addressing thermal and economic considerations effectively. This study developed a dynamic simulation model in TRNSYS for the rum solar district heating plant with an air source heat pump and a gas boiler. The validity of the model was examined in detail using long-term monitoring data of the system. Both component-level validation and loop validation showed the performance of solar collector field, air-source heat pump, and the tank could be closely fit. The simulated system successfully replicated the energy conversion efficiency of the actual system, which was demonstrated with the simulated annual solar collector efficiency, heat pump COP, and the system solar fraction with error kept below 5%. Moreover, the control strategy employed in the simulation prioritized heat pump operation within a demand-response framework, thereby reducing reliance on the boiler and resulting in a system-levelized cost of heat of 62.2 EUR/MWh, compared to 68.6 EUR/MWh in the actual system. Based on the simulated system. parameter study indicates the capital cost is sensitive to solar collectors and heat pump. GenOpt and TRNSYS are employed to minimize the solar loop's net-levelized cost of heat with the aim of upscaling the heating plant. Considering the geographical constraints, maximizing collector area and tank volume can increase solar fraction by 20% and reduce sLCOH by 0.9 EUR/MWh, as shown with an 8000 m3 tank and 12,605 m3 of solar collectors. Besides, increasing the heat pump heating capacity to 3.4 MW is recommended because the system-levelized cost of heat can be further decreased by 1.1 EUR/MWh, and the CO2 emission could be decreased by 12%. The findings of the paper present a good reference for consultants and engineers in their efforts to develop solar heating systems with enhanced thermal performance along with low system-levelized costs of heat and carbon emissions.
KW - Carbon emission
KW - Dynamic simulation
KW - Economic evaluation
KW - Heat pump
KW - Solar district heating
KW - System optimization
U2 - 10.1016/j.energy.2025.134898
DO - 10.1016/j.energy.2025.134898
M3 - Journal article
AN - SCOPUS:85217929161
SN - 0360-5442
VL - 319
JO - Energy
JF - Energy
M1 - 134898
ER -
