Application of Hydroturbine Pump in Water Source Heat Pump Drainage Gravitational Potential Energy Recovery System

Abstract

In this study, an energy recovery water source heat pump (ERWSHP) system has been developed and evaluated for feasibility, parameter efficiency and energy saving potential in comparison to conventional water source heat pump (WSHP) systems. The water discharged from the heat exchanger at a height, with an elevation difference of approximately 30 m in some areas of the mountainous city of Chongqing, was utilised as gravitational potential energy (GPE) which is converted into mechanical shaft power to drive the hydroturbine pump. A prototype of the system was set up, characterised, parameter tested and optimised in the laboratory at Chongqing University. MATLAB curve tool (cftool) was utilised to fit the characteristic curves under different water heads. The test data obtained were compared with the standard supplied data to ensure that the measurement was consistent with the performance expected. The system was validated by application to an off-site office development where the hourly cooling load during summer and heating load during winter was assessed using DeST-c (Designer’s Simulation Toolkits). The influence of the parameters was also evaluated. The energy-saving rates of ERWSHP systems in summer and winter were 37.5% and 60.1%, respectively, an equivalent to a fuel reduction of 14.7 tons of coal in summer and 31.8 tons during the winter. The use of GPE would also reduce water intake and increase the total transfer efficiency from 60% to 75% for the hydroturbine pump. A saving of 1131.01 kJ per year, a peak saving rate of 20.8%, in energy consumption could be achieved using the system.

Keywords

Energy recovery Energy saving Gravitational potential Heat exchange drainage Hydroturbine pump Water source heat pump

Get full access to this article

View all access options for this article.

References

ASHRAE Green Guide: The Design, Construction and Operation of Sustainable Buildings: ASHRAE Green Tip#20: Ground Source Heat Pumps; and ASHRAE Green Tip#21: Water-loop Heat Pump Systems. Atlanta, USA, ASHRAE, 2006.

Omer AM : Ground-source heat pumps systems and applications: Renew Sustain Energy Rev 2008;12:344-371.

Tarnawski VR , Leong WH : Analysis of ground source heat pumps with horizontal ground heat exchangers for northern Japan: Renew Energy 2009;34:127-134.

Bttyttkalaca O. , Ekinci F. , Yilmaz T. : Experimental investigation of Seyhan River and Dam Lake as heat source (sink) for a heat pump: Energy 2003;28:157-169.

Hattemer B. , Kavanaugh SP : Design temperature data for surface water heating and cooling systems: ASHRAE Trans 2005;111:695-701.

JARN Ltd : A new river water source heat pump project: Heating and Refrigeration News, August 25, 1996.

Meng M. : Cavitation and mounting height of turbine pump: Electromech Technol 1987;1: 97-101.

Kahraman A. , Çelebi A. : Investigation of the performance of a heat pump using waste water as a heat source: Energies 2009;2:697-713.

Lu J. , Fan YQ , Chen J. , Xie L. : Feasible analysis to energy recycling water source heat pump system applied in mountainous topographical cities: J Hunan Univ Nat Sci 2009;12(36):90-93.

10.

Lu J. , Chen J. , Wang ZJ , Tang HY , Song JN : Water source heat pump air conditioning system with hydroturbine pump: Patent number: zl200810069820.0.

11.

Novozhenin VD and Krasil MF : Hydraulic turbine equipment and tasks of its further improvement: Hydrotech Constr 1994;28(12):693-695.

12.

Paish O. : Small hydro power: technology and current status: Renew Sustain Energy Rev 2002;6(6):537-556.

13.

Gribor VI : Ways to increase the reliability and operating life of hydraulic turbine equipment when reconstructing hydroelectric stations: Power Technol Eng (formerly Hydrotech Constr) 2004;28(12): 700-703.

14.

Ëdel Yu U. , Mikhailov LP , Chistyakov AM , Kharlamov A Yu : Power characteristic curve of hydraulic turbine set: Power Technol Eng 1980;14(9):941-944.

15.

Bernier MA , Bourret B. : Pumping energy and variable frequency drives: ASHRAE J 1999;41(12):37-40.

16.

Hartman TB : Design issues of variable chilled-water flow through chillers: ASHRAE Trans 1996;102:679-683.

17.

Tillack L. , Rishel JB : Proper control of HVAC variable speed pumps: ASHRAE J 1998;40(11):1-4.

18.

Chen F. , Jiang Y. : Introduction of building environment designer’s simulation toolkit (DEST) . Available at: http://www.ibpsa.org/proceedings/BS1999/BS99_A-31.pdf (accessed October 21, 2008).

19.

Da Y. , Yi JG : Overview of an integrated building simulation tool - designer’s simulation toolkit (DEST). Available at: http://www.ibpsa.org/proceedings/BS2005/BS05_1393_1400.pdf (accessed November 9, 2008).

20.

Jeter SM , Wepfer WJ , Fadel GM , Cowden NE , Dymfk AA : Variable speed drive heat pump performance: Energy 1987;12(12): 1289-1298.

21.

Lu J. , Wang ZJ : Feasibility of surface water heat pump system in Xintiandi profit in Chongqing: J Cent South Univ 2007 ;14(suppl.3):70-73.

22.

ARI Standard 500/590-98: Standard for Water Chilling Packages Using the Vapor Compression Cycle. USA, Air-Conditioning and Refrigeration Institute, 1998.