The simulation of a heat pump heating a highly insulated dwelling

Abstract

The dynamic thermal behaviour of a highly insulated dwelling and a monovalent air to water heat pump heating system have been simulated in combination. The building model employs the finite difference method to predict time and spatially dependent energy flows resulting from meteorological stimuli, ventilation and occupancy. Heat pump behaviour is simulated using static performance expressions and also two dynamic models with similar steady state output but different transient characteristics. The dynamic models are intended to represent the range of transient heat pump performance observed in experimental studies. Simulations of the building and heating system have been performed over a range of meteorological conditions by sampling a real weather data set at regular intervals throughout a heating season. Results indicated wide variations in the continuous heating energy demand pattern for a highly insulated dwelling. This caused the heating system to operate at low load for most of the heating season and placed greater importance on the dynamic behaviour of the heat pump at part load. The predicted fall in seasonal performance caused by the cycling of the heating system at part load was between 3 and 7 per cent, depending on the assumed dynamic behaviour of the heat pump.

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References

1. Oddou, J. , Space heating with heat pumps–-how does the control system and the heat distribution affect the energy requirements? CIB Symposium ‘Energy Conservation in the Built Environment’, Copenhagen, 3:151–3:163 (1979).

2. Foxley, D. M. & Weaver, D. R. , Relationship between results of laboratory tests on heat pumps and performance under field trials, CIB Symposium ‘Energy Conservation in the Built Environment’, Dublin, 6.B.26–6.B.40 (1982).

3. Mountford, D. & Freund, P. , The performance of an air-water heat pump installed in an experimental house, BSER&T 2, (4) 174 (1981).

4. ASHRAE Handbook–-Systems, American Society of Heating, Refrigeration and Air Conditioning Engineers (1976).

5. Siviour, J. B. , Energy flows in six experimental houses, CIB Symposium ‘Energy Conservation in the Built Environment’, Copenhagen, 5:23–5:32 (1979).

6. Brundrett, G. W. , User experience of well insulated houses, CIB Symposium ‘Energy Conservation in the Built Environment’, Copenhagen, 5:33–5:41 (1979).

7. Kelly, G. E. & Bean, J., Dynamic performance of a residential air-to-air heat pump, US National Bureau of Standards, Thermal Engineering Section. NBS Building Science Series 93 (March 1977).

8. Cane, R. L. D. , A ‘modified’ bin method for estimating annual heating requirements of air source heat pumps. ASHRAE Journal, September 1979, 60–63.

9. Waters, J. R. , The experimental verification of a computerised thermal model for buildings, BSER&T 1, (2) 76 (1980).

10.

10. Whittle, J. K., Energy consumption in housing, PhD Thesis, University of Newcastle upon Tyne (1979).

11.

11. van der Bruggen, R. J. A. , Energy consumption for heating and cooling in relation to building design, Technische Hogeschool, Eindhoven (1979).

12.

12. Clarke, J. A. , Computer simulation of energy exchange in buildings, CIB Symposium ‘Energy Conservation in the Built Environment’. Copenhagen, 4:145–4:155 (1979).

13.

13. McMullan, J. T. , Morgan, R. & Hughes, D. W. , The discrepancy between heat pump field and test performance: A simulation study. Energy Research 5, 83 (1981).

14.

14. Rosell, J. , Morgan, R. & McMullan, J. T. , The performance of heat pumps in service–-A simulation study, Energy Research 6, 83 (1982).

15.

15. Basnett, P. , Computer program–-HOUSE User's Guide. Electricity Council Research Centre, Memorandum ECRC/MM24 (October 1974).

16.

16. Chartered Institution of Building Services, CIBS Guide Section A3 (1980).

17.

17. Henderson, W. D., The computer modelling of electric vapour compression heat pumps. (In preparation).

18.

18. Parkin, W. H. , Beausoliel, R. W. & Kelly, G. E. , Factors affecting the performance of residential air-to-air heat pumps. ASHRAE Transactions 83, 839 (1977).

19.

19. Foxley, D. M. & Weaver, D. R. , Relating laboratory testing of heat pumps to seasonal performance. IEA Conference ‘New Energy Conservation Technologies’, Berlin, F:611 (1981).

20.

20. Geereart, B. , Experiences d'installations de pompe a chaleur. AIM Conference ‘L'Energie en 1981’, Liege, Paper 9 (1981).

21.

21. Wiltshire, T. J. & Hardy, A. C. , An investigation into the energy consumption of Swedish houses in the United Kingdom climate. CIB Symposium ‘Energy Conservation in the Built Environment’, Dublin, 5:211–5:224 (1982).

22.

22. Holmes, M. J. , An ‘Example Year’ for the calculation of energy demand in building. Build. Serv. Eng. 45, 196 (1978).