Article
Green & Sustainable Science & Technology
Jere Knuutinen, Herman Book, Vesa Ruuskanen, Antti Kosonen, Paula Immonen, Jero Ahola
Summary: This paper examines four different control methods for DHW heating in a building with a GSHP and a PV system. The main control method aims to minimize DHW heating costs by utilizing market information and PV production output forecast, showing significant cost savings even with forecasting errors.
Article
Thermodynamics
Yongbao Chen, Zhisen Chen, Zhe Chen, Xiaolei Yuan
Summary: This paper proposes an integrated energy system based on a solar-assisted ground source heat pump for heating rural houses, optimizing operational modes to improve energy efficiency and reduce electricity demand.
APPLIED THERMAL ENGINEERING
(2021)
Article
Construction & Building Technology
Xueyou Zhang, Enyu Wang, Liansheng Liu, Chengying Qi, Jinyu Zhen, Ying Meng
Summary: This study examines the operational performance of a hybrid solar ground source heat pump (HSGSHP) system at Hebei University of Technology. The results show that the solar-assisted ground source heat pump (SAGSHP) system significantly improves the performance of the HSGSHP system, increasing its coefficient of performance (COP). Additionally, increasing the proportion of heat supply from the SAGSHP system improves the performance of the HSGSHP system.
ENERGY AND BUILDINGS
(2022)
Article
Green & Sustainable Science & Technology
Bo Xu, Dengyun Wang, Zhaohai Li, Zhenqian Chen
Summary: A new type of solar-assisted heat pump drying system can adapt to different outdoor environments by selecting and switching more efficient and energy-saving drying modes, leading to good performance under different modes.
Article
Green & Sustainable Science & Technology
Rui Dai, Ran Tian, Siyu Zheng, Mingshan Wei, GuoHua Shi
Summary: This paper proposes an LNG vaporization system using a solar-assisted heat pump for defrosting and auxiliary heating, with the enhancement of heat pump performance and LNG preheating by a low-temperature LNG bypass. The system's performance throughout the year and under typical meteorological conditions was analyzed, showing significant improvements in COP and heat collection efficiency with the LNG bypass.
Article
Green & Sustainable Science & Technology
T. Zhang, Y. F. Zhang, Z. R. Shi, Q. F. Li, J. Y. Cai
Summary: A hybrid PV/T collector/evaporator was designed and a hybrid system named PV-SAHP/GHP was proposed. Outdoor experiments were conducted to compare the operating characteristics of different modes. The results showed that the GHP-PV/T mode had satisfactory energy-saving effect while the PV-SAHP mode met the temperature demand but had unsatisfactory energy conservation effect. It is recommended to operate the GHP-PV/T mode during intense radiation and the PV-SAHP mode otherwise to balance the thermal performance and energy-saving benefits.
Article
Green & Sustainable Science & Technology
Zihao Qi, Yingling Cai, Yunxiang Cui
Summary: This study aims to investigate the operational characteristics of the solar-ground source heat pump system (SGSHPS) in Shanghai under different operation modes. It concludes that tandem operation mode 1 is the optimal mode for winter operation in terms of energy efficiency.
Article
Thermodynamics
Dongwei Zhang, Zhao Gao, Chenglei Fang, Chao Shen, Hang Li, Xiang Qin
Summary: A solar-assisted waste water source heat pump hot water system was built and analyzed in this study. The sensitivity analysis revealed that the pump flowrate and the storage capacity of the heat exchange tank were critical factors for system performance, while the azimuth and inclination angle of the solar collector had minimal influence. By optimizing the parameters, the improved system achieved more stable hot water temperature in winter with significant reduction in energy consumption.
Article
Thermodynamics
Minwoo Lee, Jinyoung Kim, Hyun Ho Shin, Wonhee Cho, Yongchan Kim
Summary: The adoption of appropriate alternative refrigerants can effectively reduce the energy consumption and CO2 emissions of heat pump systems. However, there is limited investigation on alternative refrigerants for ground-source heat pump (GSHP) and solar-assisted ground-source heat pump (SGSHP) systems, which still use conventional refrigerants. This study compares the life cycle climate performance (LCCP) and primary energy consumption (PEC) of GSHP and SGSHP systems using conventional and alternative refrigerants, and suggests different optimal choices based on regional factors.
Article
Energy & Fuels
Konstantin Osintsev, Sergei Aliukov, Yuri Prikhodko
Summary: The aim of this scientific research is to experimentally determine the exergy losses of a ground heat pump and further optimize operating modes for efficiency. New methods of approximation of piecewise linear functions are used to assess exergetic flows and develop prerequisites for anergy analysis of energy sources. The study resulted in specific values for the heat pump's performance and energy losses.
Article
Green & Sustainable Science & Technology
Mohammad Nahavandinezhad, Alireza Zahedi
Summary: This study investigated the feasibility of utilizing geothermal and solar energy to replace natural gas in Sistan/Baluchestan province, Iran. By modeling and evaluating four solar-assisted ground source heat pump systems, the optimal solution was found to have high investment return and environmental benefits.
Article
Thermodynamics
Mohamed R. H. Abdel-Salam, Aqeel Zaidi
Summary: The study found that ground-source heat pump systems perform well during the cooling season, reducing total power consumption and operating costs significantly.
APPLIED THERMAL ENGINEERING
(2021)
Article
Thermodynamics
Muhammad Yahya, Hendriwan Fahmi, Rosdanelli Hasibuan, Ahmad Fudholi
Summary: This study evaluated a hybrid solar-assisted heat pump dryer (HS-AHPD) for drying paddy and found that it decreased the weight of paddy with high efficiency and improved product quality. The system used R22 as a working fluid and achieved an average drying rate of 8.34 kg/s, specific moisture extraction rate (SMER) of 0.44 kg/kWh, and specific energy consumption (SEC) of 4.69 kWh/kg. The HS-AHPD's thermal efficiency and exergy efficiency were 29.1% and 18.4%, respectively. The furnace and solar collector contributed significant energy to the system. The drying process resulted in higher head rice yield, lower broken rice, and lower rice grouts.
CASE STUDIES IN THERMAL ENGINEERING
(2023)
Article
Construction & Building Technology
Mohamed R. H. Abdel-Salam, Aqeel Zaidi, Matt Cable
Summary: This paper is the second part of a study on the performance of ground-source heat pumps in single-family detached houses in Canada, focusing on the heating performance of three vertical closed-loop water-to-air GSHP systems. The results show that the GSHP systems were able to meet the peak heating load without using auxiliary heating, with GSHP A having the highest coefficient of performance due to its variable speed compressor.
ENERGY AND BUILDINGS
(2021)
Article
Thermodynamics
Sung Joo Hong, Kyung Jin Bae, Thi-Nhan Nguyen, Han Gil Kim, In Gwan Kim, Nam Yong Kim, Oh Kyung Kwon, Chan Woo Park
Summary: The study proposed a waste heat-driven hybrid lithium bromide-water absorption system for simultaneous steam generation and refrigeration effects. The system, with a cooling capacity of 350 kW, demonstrated good performance during the experimental phase with payback periods of 2.79 and 2.36 years.
APPLIED THERMAL ENGINEERING
(2022)
Article
Energy & Fuels
Min Gyung Yu, Yujin Nam
Article
Energy & Fuels
Min Gyung Yu, Yujin Nam
Article
Energy & Fuels
Yong-Dae Jeong, Min Gyung Yu, Yujin Nam
Article
Energy & Fuels
Min Gyung Yu, Gregory S. Pavlak
Summary: This study introduces an uncertainty-aware transactive control framework for coordinating thermal energy storage assets of multiple buildings, aiming to achieve energy cost savings and increased system flexibility.
Article
Thermodynamics
Min Gyung Yu, Gregory S. Pavlak
Summary: Developing intelligent building control strategies has become a multi-objective problem, requiring balancing performance across various factors. Implementing multi-objective optimal controls in buildings is challenging due to complexity and computational burden. This study extracts near-optimal rule sets from a database of non-dominated solutions using multi-objective model predictive control.
Article
Energy & Fuels
Min Gyung Yu, Gregory S. Pavlak
Summary: With the increasing deployment of distributed energy resources, efficient operation of electric grid systems has become challenging due to demand and supply fluctuations. This study developed a risk-averse stochastic optimal dispatch model for portfolios with thermal energy storage to mitigate financial loss. Two simulation case studies were conducted to evaluate the performance of the risk-averse controller and demonstrated significant cost savings of 42.4% with larger thermal energy storage capacity.
Article
Energy & Fuels
Sarmad Hanif, Monish Mukherjee, Shiva Poudel, Min Gyung Yu, Rohit A. Jinsiwale, Trevor D. Hardy, Hayden M. Reeve
Summary: This paper presents a modeling and simulation platform for electric distribution grids that estimates overall power demand during extreme weather conditions. The effectiveness of the platform is demonstrated through estimation of electricity demand during the winter storm Uri in 2021 and hypothetical scenarios involving distributed energy resources, weatherization, and load electrification. Integration of distributed solar PV and storage improves local energy utilization and reduces potential unmet energy demand.
Proceedings Paper
Automation & Control Systems
Min Gyung Yu, Gregory S. Pavlak
2020 AMERICAN CONTROL CONFERENCE (ACC)
(2020)