Article
Green & Sustainable Science & Technology
Qingsong Ji, Huan He, Scott Kennedy, Jingwen Wang, Zixuan Peng, Zhe Xu, Yanxia Zhang
Summary: The study focuses on using wind energy as an alternative source to reduce energy consumption and achieve the greenhouse gas net-zero emissions targets set by the Climate Change (Scotland) Act. A wind turbine-driven heat pump system is designed to provide heating for detached houses, and performance indicators are proposed to evaluate the system. Results show that wind turbines can meet energy requirements and reduce CO2 emissions, indicating the environmental benefits of the system.
SUSTAINABLE ENERGY TECHNOLOGIES AND ASSESSMENTS
(2022)
Article
Thermodynamics
Aki Pesola
Summary: This paper presents a new optimization approach for hybrid heating systems that combine centralized district heating assets and decentralized heat pumps. A modeling tool was developed to assess the impact of adding heat pumps to the existing district heating system. The results show that optimal use of heating assets can significantly reduce operating expenditure. To fully realize the benefits, heat pumps should be utilized to provide ancillary services and receive compensation for feeding heat into the district heating network. Sensitivity analysis was conducted to evaluate the robustness of the modeling results.
Article
Construction & Building Technology
Bo Gao, Xiaoyue Zhu, Xiaojiao Yang, Yanping Yuan, Nanyang Yu, Ji Ni
Summary: The study tested the operation performance of 26 GSHP systems in Sichuan, Chongqing, and Shaanxi and found that the average coefficient of performance (COP) was less than 3.0 under heating conditions, failing to meet the national standards for energy-saving requirements. Typical problems were identified, and it was recommended to use ground-coupled heat pump (GCHP) systems in the western regions of China to improve operation performance.
JOURNAL OF BUILDING ENGINEERING
(2021)
Article
Thermodynamics
Shaoliang Zhang, Shuli Liu, Jihong Wang, Yongliang Li, Zhibin Yu
Summary: Insufficient heating capacity and low coefficient of performance have hindered the application of air source heat pump systems in cold regions. This study proposes an indirect expansion solar-assisted air source heat pump system to improve the heating performance. An optimized control method is proposed to tackle the refrigerant redistribution problem. The experimental results show that the solar heat pump mode has a higher coefficient of performance compared to the air source heat pump mode.
APPLIED THERMAL ENGINEERING
(2023)
Article
Energy & Fuels
Weituo Sun, Xiaoming Wei, Baochang Zhou, Chungui Lu, Wenzhong Guo
Summary: Multi-span greenhouses in northern China consume excessive amounts of energy for heating. A greenhouse heating system utilizing energy transfer between greenhouses has been designed to address this issue, resulting in reduced heating costs and improved energy utilization efficiency.
Article
Construction & Building Technology
Shanguo Zhao, Xiaosong Zhang, Caihua Liang, Shifang Huang
Summary: This paper proposes a multi-mode regeneration HTHP (High Temperature High Pressure) system to address the shortcomings of traditional building air conditioning systems in terms of cooling and heating sources. The working principle and modes of the system are described in detail. The system is applied in an energy-saving retrofit project and control strategies, as well as an evaluation calculation method, are provided. The cooling performance, heating performance, and moisture absorption characteristics of the HTHP system are calculated on an hourly, daily, and annual basis. The results indicate that the system achieves average comprehensive cooling and heating efficiencies of 4.34 and 3.12, respectively, with annual comprehensive cooling and heating operation efficiencies of 4.47 and 3.49. The average regeneration efficiency during the test is 4.34 kg/kWh, which is relatively unaffected by external conditions. During winter operation, moisture migration between the solution and air occurs through evaporation and absorption, with comprehensive moisture absorption accounting for approximately 3.9% of the whole year.
SUSTAINABLE CITIES AND SOCIETY
(2023)
Article
Green & Sustainable Science & Technology
Angeliki Kitsopoulou, Antonis Zacharis, Nikolaos Ziozas, Evangelos Bellos, Petros Iliadis, Ioannis Lampropoulos, Eleni Chatzigeorgiou, Komninos Angelakoglou, Nikolaos Nikolopoulos
Summary: This paper investigates different heating configurations utilizing renewable thermal sources in conjunction with a heat pump-based system, aiming to determine the optimal configuration in terms of efficiency. Through dynamic energy simulations, it is demonstrated that renewable thermally driven heat pumps are more efficient than conventional air-source ones. The most effective and economical design is found to be the dual-source system, while the ground-source configuration is the most expensive.
Article
Energy & Fuels
Evangelos Bellos, Christos Tzivanidis
Summary: The study investigates a ground source heat pump system for space heating purposes with boreholes, examining ten parameters related to the heat pump cycle and the geothermal unit. The study highlights the system's performance under nominal design conditions and demonstrates the influence of the parameters on the overall system performance and geothermal characteristics.
Article
Thermodynamics
Lingyun Xie, Muxing Zhang, Shifang Huang, Shanguo Zhao, Xiaosong Zhang
Summary: Heating tower heat pumps (HTHPs) are rapidly evolving due to their high performance and adaptability, with this study proposing a framework to optimize their design parameters. The research conducted case studies in 21 locations across different climate regions to investigate energy and cost savings, determining that increasing certain design parameters can improve performance but may also lead to higher energy consumption and costs.
ENERGY CONVERSION AND MANAGEMENT
(2022)
Article
Chemistry, Multidisciplinary
Evangelos Bellos, Dimitrios Tsimpoukis, Panagiotis Lykas, Angeliki Kitsopoulou, Dimitrios N. Korres, Michail Gr. Vrachopoulos, Christos Tzivanidis
Summary: High-temperature heat pumps are a promising alternative to conventional boilers, providing hot water in the range of 70-80 degrees C for efficient indoor heating. This study investigates the performance of a high-temperature heat pump using R1234ze(E) as the working medium in Greek climate conditions. The results show that the high-temperature heat pump outperforms a conventional oil boiler in terms of energy, financial, and environmental aspects.
APPLIED SCIENCES-BASEL
(2023)
Article
Thermodynamics
Jie Lu, Yitian Tang, Zhiyuan Li, Guoqing He
Summary: This study compared the seasonal energy performance of serial and parallel configurations of solar-assisted heat pump systems in 39 cities across China. Results showed that a parallel system with ASHP as auxiliary source generally performs better, while a serial system is favored when electrical heating is the auxiliary source. High solar radiation and warm climates are beneficial for parallel configuration, while a more efficient WSHP favors the serial configuration.
APPLIED THERMAL ENGINEERING
(2021)
Article
Construction & Building Technology
Fujen Wang, Kusnandar, Hungwen Lin, Minghua Tsai
Summary: This study focuses on analyzing the energy efficiency of a water heating system in a university dormitory retrofitted with a heat pump system. The results indicate that the retrofitting of a heat pump system can lead to improved energy efficiency and energy savings.
Article
Thermodynamics
Yuanhong Han, Wei Song, Zihan Wang, Qihang Lai, Ziying Song, Wenhua Ju
Summary: With the promotion of rural revitalization in China, mid-deep-groundwater heat pump systems have played a significant role in the efficient utilization of geothermal energy. In this study, a system was constructed and operated in Mei County, and an analysis of geothermal resource and building energy demand was conducted to optimize the operation plan.
CASE STUDIES IN THERMAL ENGINEERING
(2023)
Review
Energy & Fuels
Eneja Osterman, Uros Stritih
Summary: Heat pumps are easy to use and can bring low-temperature heat sources to a higher temperature, utilizing renewable energy sources and waste heat to reduce fossil fuel demand and greenhouse gas emissions. They provide both heating and cooling, operating simultaneously with high efficiency. However, to fully exploit their potential, thermal energy storage units are necessary for continuous and economical operation.
JOURNAL OF ENERGY STORAGE
(2021)
Article
Thermodynamics
Chenjiyu Liang, Xianting Li, Xiangjun Meng, Wenxing Shi, Junqiang Gu, Baolong Wang, Yanbo Lv
Summary: In this study, a new type of air source heat pump was developed to provide stable heating during defrosting by using multiple air source heat exchangers and anti-icing fluid pipelines. Test results showed that the heating capacity decay rate during defrosting can reach within 20%. After optimization, the heating capacity decay rate can be reduced to within 10%.
APPLIED THERMAL ENGINEERING
(2023)
Article
Energy & Fuels
Jiewen Deng, Qingpeng Wei, Yangyang Qian, Hui Zhang
Article
Construction & Building Technology
Jiewen Deng, Qingpeng Wei, Mei Liang, Shi He, Hui Zhang
ENERGY AND BUILDINGS
(2019)
Article
Chemistry, Multidisciplinary
Jiewen Deng, Qingpeng Wei, Shi He, Mei Liang, Hui Zhang
APPLIED SCIENCES-BASEL
(2019)
Article
Energy & Fuels
Jiewen Deng, Qingpeng Wei, Shi He, Mei Liang, Hui Zhang
Article
Construction & Building Technology
Jiewen Deng, Wenbo Qiang, Chenwei Peng, Qingpeng Wei, Wanlong Cai, Hui Zhang
Summary: This paper proposes a method that combines numerical simulation, modified finite linear heat source model, and analytical solutions to rapidly and accurately calculate the maximum annual accumulative heat extraction of deep borehole heat exchangers (DBHE) at the design stage. By studying the effects of key factors and proposing a system design method based on the maximum heat extraction, the stability, safety, and feasibility of long-term operation can be guaranteed.
JOURNAL OF BUILDING ENGINEERING
(2022)
Article
Construction & Building Technology
Jiewen Deng, Wenbo Qiang, Chenwei Peng, Qingpeng Wei, Hui Zhang
Summary: This study conducted field tests and analysis on the operation performance of chillers in large-scale commercial buildings, aiming to improve their energy efficiency. A systematic optimization method for chillers was proposed, considering external factors (cooling load prediction) and internal factors (energy performance model). A new control strategy was proposed based on the models to achieve significant energy-saving effects.
ENERGY AND BUILDINGS
(2023)
Article
Construction & Building Technology
Jiewen Deng, Chenwei Peng, Yangyang Su, Wenbo Qiang, Qingpeng Wei
Summary: This paper proposes a semi-analytical method to evaluate the long-term operation performance of DBHEs array, indicating that the line space has a significant impact on heat extraction. Additionally, inclined DBHEs are recommended for practical projects with limited space.
ENERGY AND BUILDINGS
(2023)
Article
Construction & Building Technology
Samiran Khorat, Debashish Das, Rupali Khatun, Sk Mohammad Aziz, Prashant Anand, Ansar Khan, Mattheos Santamouris, Dev Niyogi
Summary: Cool roofs can effectively mitigate heatwave-induced excess heat and enhance thermal comfort in urban areas. Implementing cool roofs can significantly improve urban meteorology and thermal comfort, reducing energy flux and heat stress.
ENERGY AND BUILDINGS
(2024)
Article
Construction & Building Technology
Qi Li, Jiayu Chen, Xiaowei Luo
Summary: This study focuses on the vertical wind conditions as a main external factor that limits the energy assessment of high-rise buildings in urban areas. Traditional tools for energy assessment of buildings use a universal vertical wind profile estimation, without taking into account the unique wind speed in each direction induced by the various shapes and configurations of buildings in cities. To address this limitation, the study developed an omnidirectional urban vertical wind speed estimation method using direction-dependent building morphologies and machine learning algorithms.
ENERGY AND BUILDINGS
(2024)
Article
Construction & Building Technology
Xiaojun Luo, Lamine Mahdjoubi
Summary: This paper presents an integrated blockchain and machine learning-based energy management framework for multiple forms of energy allocation and transmission among multiple domestic buildings. Machine learning is used to predict energy generation and consumption patterns, and the proposed framework establishes optimal and automated energy allocation through peer-to-peer energy transactions. The approach contributes to the reduction of greenhouse gas emissions and enhances environmental sustainability.
ENERGY AND BUILDINGS
(2024)
Article
Construction & Building Technology
Ying Yu, Yuanwei Xiao, Jinshuai Chou, Xingyu Wang, Liu Yang
Summary: This study proposes a dual-layer optimization design method to maximize the energy sharing potential, enhance collaborative benefits, and reduce the storage capacity of building clusters. Case studies show that the proposed design significantly improves the performance of building clusters, reduces energy storage capacity, and shortens the payback period.
ENERGY AND BUILDINGS
(2024)
Article
Construction & Building Technology
Felix Langner, Weimin Wang, Moritz Frahm, Veit Hagenmeyer
Summary: This paper compares two main approaches to consider uncertainties in model predictive control (MPC) for buildings: robust and stochastic MPC. The results show that compared to a deterministic MPC, the robust MPC increases the electricity cost while providing complete temperature constraint satisfaction, while the stochastic MPC slightly increases the electricity cost but fulfills the thermal comfort requirements.
ENERGY AND BUILDINGS
(2024)
Article
Construction & Building Technology
Somil Yadav, Caroline Hachem-Vermette
Summary: This study proposes a mathematical model to evaluate the performance of a Double Skin Facade (DSF) system and its impact on indoor conditions. The model considers various design parameters and analyzes their effects on the system's electrical output and room temperature.
ENERGY AND BUILDINGS
(2024)
Article
Construction & Building Technology
Ruijun Chen, Holly Samuelson, Yukai Zou, Xianghan Zheng, Yifan Cao
Summary: This research introduces an innovative resilient design framework that optimizes building performance by considering a holistic life cycle perspective and accounting for climate projection uncertainties. The study finds that future climate scenarios significantly impact building life cycle performance, with wall U-value, windows U-value, and wall density being major factors. By using ensemble learning and optimization algorithms, predictions for carbon emissions, cost, and indoor discomfort hours can be made, and the best resilient design scheme can be selected. Applying this framework leads to significant improvements in building life cycle performance.
ENERGY AND BUILDINGS
(2024)