Comparison of long-term performance and the initial cost of the horizontal ground source heat pump with the air source heat pump in hot regions

Document Type : Research Article

Authors

1 Department of Mechanical Engineering, Sharif University of Technology, Tehran, Iran

2 Mechanical Engineering/Sharif University/Assistant Professor

Abstract

Ground-source heat pumps have received much attention due to their high coefficient of performance. In these systems, the ground is used as a sink/source for the heat pump,­ and the heat transfer between the ground and the heat pump is performed by the ground heat exchanger. In this study, the long-term performance and initial cost of these systems have been compared with conventional air-source heat pumps in a hot region. Both systems are numerically simulated. The performance of the systems is compared for cooling of a residential building in Bandar-Abbas, Iran. Moreover, the effect of various system operating parameters, i.e., ground heat exchanger length, pipe spacing, depth, and pipe diameter, have been studied. According to results, the five-year coefficient of performance and exergy efficiency of ground-source systems is 19.9% to 24.30% and 5.95% to 6.55%, respectively, more than that of the air-source system. However, 1.2 to 2.5 million Tomans is needed as the installation cost for each kW of maximum building load per year. Also, it is demonstrated that by reducing the length of the ground heat exchanger, the initial cost is reduced, and the system performance improves. The pipe spacing is the most influential factor in the required ground surface, the depth has the most impact on the initial cost and the system performance, and the pipe diameter does not affect the system performance.

Keywords

Main Subjects

References

[1] M. Hanif, T. Mahlia, A. Zare, T. Saksahdan, H. Metselaar, Potential energy savings by radiative cooling system for a building in tropical climate, Renewable and sustainable energy reviews, 32 (2014) 642-650.
[2] Y. Yuan, X. Cao, L. Sun, B. Lei, N. Yu, Ground source heat pump system: A review of simulation in China, Renewable and Sustainable Energy Reviews, 16(9) (2012) 6814-6822.
[3] W. Zhang, H. Yang, L. Fang, P. Cui, Z. Fang, Study on heat transfer of pile foundation ground heat exchanger with three-dimensional groundwater seepage, International Journal of Heat and Mass Transfer, 105 (2017) 58-66.
[4] P. Congedo, G. Colangelo, G. Starace, CFD simulations of horizontal ground heat exchangers: A comparison among different configurations, Applied Thermal Engineering, 33 (2012) 24-32.
[5] M. Habibi, A. Hakkaki-Fard, Evaluation and improvement of the thermal performance of different types of horizontal ground heat exchangers based on techno-economic analysis, Energy Conversion and Management, 171 (2018) 1177-1192.
[6] M. Li, A.C. Lai, Analytical model for short-time responses of ground heat exchangers with U-shaped tubes: model development and validation, Applied energy, 104 (2013) 510-516.
[7] J. Chen, L. Xia, B. Li, D. Mmereki, Simulation and experimental analysis of optimal buried depth of the vertical U-tube ground heat exchanger for a ground-coupled heat pump system, Renewable energy, 73 (2015) 46-54.
[8] Y. Li, S. Geng, X. Han, H. Zhang, F. Peng, Performance evaluation of borehole heat exchanger in multilayered subsurface, Sustainability, 9(3) (2017) 356.
[9] V. C. Mei, Heat transfer of buried pipe for heat pump application, Journal of solar energy engineering, 113(1) (1991) 51-55.
[10] K. Kupiec, B. Larwa, M. Gwadera, Heat transfer in horizontal ground heat exchangers, Applied Thermal Engineering, 75 (2015) 270-276.
[11] N. Kayaci, H. Demir, Numerical modelling of transient soil temperature distribution for horizontal ground heat exchanger of ground source heat pump, Geothermics, 73 (2018) 33-47.
[12] G. Gan, Dynamic thermal performance of horizontal ground source heat pumps–The impact of coupled heat and moisture transfer, Energy, 152 (2018) 877-887.
[13] Z. Zhao, R. Shen, W. Feng, Y. Zhang, Y. Zhang, Soil thermal balance analysis for a ground source heat pump system in a hot-summer and cold-winter region, Energies, 11(5) (2018) 1206.
[14] in:  ASHRAE handbook: heating, ventilating, and air-conditioning applications, Inch-Pound Edition, American Society of Heating, Refrigerating and Air-Conditioning Engineers 2015.
[15] I. Staffell, D. Brett, N. Brandon, A. Hawkes, A review of domestic heat pumps, Energy & Environmental Science, 5(11) (2012) 9291-9306.
[16] M. Habibi, A. Amadeh, A. Hakkaki-Fard, A numerical study on utilizing horizontal flat-panel ground heat exchangers in ground-coupled heat pumps, Renewable Energy, 147 (2020) 996-1010.
[17] S.P. Kavanaugh, K.D. Rafferty, Geothermal heating and cooling: design of ground-source heat pump systems, ASHRAE, (2014).
[18] A.Sedaghat, M.Habibi, A. Hakkaki-Fard, A novel ground thermal recovery system for horizontal ground heat exchangers in a hot climate, Energy Conversion and Management,  (2020).
[19] Y.A. Cengel, M.A. Boles, Thermodynamics: An Engineering Approach 6th Editon (SI Units), The McGraw-Hill Companies, Inc., New York, (2007).
[20] M. Habibi, A. Hakkaki-Fard, Long-term energy and exergy analysis of heat pumps with different types of ground and air heat exchangers, International Journal of Refrigeration, 100 (2019) 414-433.
[21] P.D. Metz, Ground coupled heat-pump-system experimental results, NASA STI/Recon Technical Report N, 84 (1983).
[22] Weather data. <https://energyplus.net/weather-location/asia_wmo_region_2/IRN//IRN_Bandar.Abass.408750_ITMY.>, (2019).
[23] J. Luo, H. Zhao, S. Gui, W. Xiang, J. Rohn, P. Blum, Thermo-economic analysis of four different types of ground heat exchangers in energy piles, Applied Thermal Engineering, 108 (2016) 11-19.
[24] N. Kayaci, H. Demir, Long time performance analysis of ground source heat pump for space heating and cooling applications based on thermo-economic optimization criteria, Energy and Buildings, 163 (2018) 121-139.
[25] Price of polyethylen pipe. <http://www.bill.loolehmarket.com>, (2018).
[26] Excavation costs. <http://takhrib-saakhteman.ir>,  (2019).
Amirkabir Journal of Mechanical Engineering
Volume 53, Issue 5 (Special Issue)
August 2021
Pages 3317-3334

Files

Share

How to cite

Statistics