Title page
Contents
Glossary 4
Key Messages 12
Executive Summary 13
1. Project Profile 16
1.1. Aims 16
1.2. Approach 16
1.3. Timeline 17
2. Site Selection and Installations Monitored 18
2.1. Phase 1 : 2014 18
2.2. Phase 2 : 2015 18
2.3. Sites monitored 18
3. Monitoring Equipment and Data Analysis 22
3.1. Monitoring requirements 22
3.2. Monitoring equipment used 23
3.3. Data analysis 24
4. Results 25
4.1. Summary of first-year performance data 25
4.2. Measurement uncertainty 26
4.3. System efficiency - SPFH2 and SPFH4 26
4.4. System performance for selected groups of installations 29
4.5. Tapestries of operational times 35
4.6. Heat pump cycling 35
4.7. Efficiency of domestic hot water production 40
4.8. Efficiency as a function of heat delivered 44
4.9. Efficiency variation by time of year 46
4.10. Efficiency variation by system temperatures 47
4.11. Breakdown of electricity usage by auxiliaries 50
4.12. Qualitative observations 53
5. Examples of Good Performance 54
5.1. Site 01 - highest system performance 54
5.2. Site 17 - second-highest system performance 57
5.3. Site 27 - third-highest system performance 62
6. Examples of Low Performance 65
6.1. Site 40 - lowest system performance 65
6.2. Site 18 - second-lowest system performance 70
7. Heat Metering Issues 75
7.1. Incorrectly mounted temperature sensors 75
7.2. Incorrectly mounted flow meter 78
7.3. Incorrectly configured heat calculator 79
8. Estimated Carbon & Fuel Bill Savings 80
9. Findings and Conclusions 81
9.1. Findings 81
9.2. Remarks 81
9.3. Conclusions 83
9.4. Suggestions for further work 83
9.5. Further analysis 83
10. Bibliography 84
Appendix A. Definition of seasonal performance factor 86
SEPEMO system boundaries 86
Appendix B. Monitoring equipment 89
EpiSensor Wireless Monitoring System 89
Calibration of temperature sensors 92
Calibration checks of electricity monitors 92
Data management 93
Installation of monitoring equipment 94
Appendix C. Data analysis 103
Data processing software 103
Data analysis methodology 105
Appendix D. Estimation of DHW heat at site 17 109
Appendix E. Estimation of uncertainty of measurement of SPF 113
Appendix F. Summary of heat pump installations 118
Appendix G. Calibration of temperature sensors 122
Appendix H. Calculation method: estimation of the power drawn by internal circulating pumps and auxiliary heaters 131
Appendix I. Use of strap-on temperature sensors 137
Table 1. Summary of performance statistics 13
Table 2. Project timeline 17
Table 3. Summary of sites monitored (phase 1) 20
Table 4. Summary of sites monitored (phase 2) 21
Table 5. Summary of performance data for the first year of monitoring 25
Table 6. SPFH4 in alternate SH and DHW modes 40
Table 7. Breakdown of electricity usage on each system 50
Table 8. SPFH4 values that must be achieved by heat pumps to break even with alternative technologies 80
Table 9. Types of EpiSensor sensors used in this project 92
Table 10. Summary of heat pump installations 120
Table 11. Lookup table correction function for TES firmware V2.83 & V2.84 123
Table 12. Temperature sensor calibration error measurements (V2.83 & V2.84 equipment) 128
Table 13. Temperature sensor calibration error measurements (V2.87 equipment) 129
Table 14. Estimated systematic errors of strap-on temperature measurement (sink temperatures) 138
Table 15. Estimated systematic errors of strap-on temperature measurement (source temperatures) 139
Figure 1. Histogram showing system performance of all systems monitored for a year 14
Figure 2. SPFH4 values showing estimated uncertainties of measurement 26
Figure 3. Histogram showing heat pump performance of all systems monitored for a year 27
Figure 4. Histogram showing system performance of all systems monitored for a year 28
Figure 5. Histogram of systems that provide space heating only 29
Figure 6. Histogram of systems that provide both space heating and domestic hot water 30
Figure 7. Histogram of systems where auxiliary heat was used 30
Figure 8. Histogram of systems where auxiliary heat was not used 31
Figure 9. Histogram of systems that use underfloor heating 32
Figure 10. Histogram of systems that use only radiators 32
Figure 11. Histogram of systems using horizontal ground arrays 33
Figure 12. Histogram of systems using vertical boreholes 33
Figure 13. Histogram of systems using strap-on temperature sensors for heat metering 34
Figure 14. Tapestry of operation for site 30 during January 2015 35
Figure 15. Site 10 cycling behaviour 36
Figure 16. Site 10 electrical & thermal power and key temperatures on 23-24 January 2015 37
Figure 17. Site 48 daily average run times 38
Figure 18. Site 48 heat pump electrical and thermal power profile before and after the refrigerant circuit was recharged 38
Figure 19. Site 48 short run times during mild weather 39
Figure 20. Daily maximum temperature of output to DHW coil on sites providing DHW from the heat pump 41
Figure 21. Site 04 daily maximum temperature of output to DHW coil 42
Figure 22. Site 17 daily maximum temperature of output to DHW coil 42
Figure 23. Site 17 typical "high temperature" DHW heating cycle and immersion heater operation during the following 24 hours 43
Figure 24. Site 37 daily SPFH4 for DHW and SH modes, showing the effect of increased use of immersion heater after March 2015 44
Figure 25. Highest performance system: site 01 histograms of daily SPFH2 and SPFH4 based on heat generated 45
Figure 26. Lowest performance system: site 40 histograms of daily SPFH2 and SPFH4 based on heat generated 45
Figure 27. Site 01 performance data timeline 46
Figure 28. Site 05 performance data timeline 46
Figure 29. Variation of Carnot COP with temperature lift 47
Figure 30. Daily SPFH4 plotted against daily average temperature lift (all systems) 48
Figure 31. Site 01 SPFH4 vs temperature lift (grouped by output temperature) 49
Figure 32. Breakdown of electricity usage on each system 50
Figure 33. Site 01 weekly electricity usage 51
Figure 34. Site 04 weekly electricity usage 51
Figure 35. Site 35 weekly electricity usage 52
Figure 36. Site 35 electricity usage breakdown for 1 winter day 52
Figure 37. Site 37 weekly electricity usage 52
Figure 38. Site 01 system schematic 54
Figure 39. Site 01 12-month temperature profile 55
Figure 40. Site 01 operating profile during 5 hours on 5th January 2015 56
Figure 41. Site 17 system schematic 57
Figure 42. Site 17 weekly heat output to DHW and SH 57
Figure 43. Site 17 histogram of temperature lift based on heat generated 58
Figure 44. Site 17 tapestry of operation during January 2015 59
Figure 45. Site 17 weekly electricity usage breakdown 59
Figure 46. Site 17 12-month temperature profile 60
Figure 47. Site 17 operating profile on 5th January 2015 61
Figure 48. Site 27 system schematic 62
Figure 49. Site 27 12-month temperature profile 63
Figure 50. Site 27 operating profile on 19th January 2015 64
Figure 51. Site 40 system schematic 65
Figure 52. Site 40 12-month temperature profile 67
Figure 53. Site 40 temperature profile for a typical winter day 02 February 2015 68
Figure 54. Site 40 heat pump output temperature 01-07 September 2014 69
Figure 55. Site 40 apartment circulating pumps electricity usage 69
Figure 56. Site 18 system schematic 70
Figure 57. Site 18 12-month temperature profile 71
Figure 58. Site 18 operating profile for a typical winter day on 19th January 2015 72
Figure 59. Site 18 breakdown of electricity usage 73
Figure 60. Site 18 daily SPF values 73
Figure 61. Site 18 total circulating pumping power 73
Figure 62. Incorrectly designed sensor fittings 75
Figure 63. A made-up fitting and a correct fitting used on the same heat meter 76
Figure 64. Strapped on temperature sensors 76
Figure 65. Loose temperature sensors on the wrong pipes 77
Figure 66. Temperature sensor leads extended 78
Figure 67. Mechanical flow meter incorrectly mounted 78
Figure 68. Incorrectly mounted vortex flow meters 79
Figure A1. SEPEMO system boundaries 87
Figure B1. EpiSensor wireless monitoring system architecture 90
Figure B2. Illustration of EpiSensor interval & delta data logging 91
Figure B3. Schematic of the data logging, management and analysis system 93
Figure B4. Gateway computer with 3G modem 94
Figure B5. High-gain cellular antenna 95
Figure B6. ZEM-61 3-phase monitors in use on circuits in a distribution board 96
Figure B7. ZEM-61 3-phase electricity monitor with current transformers installed in cable trunking 96
Figure B8. ZEM-61 3-phase electricity monitor connected to a 3-phase heat pump supply circuit 97
Figure B9. ZEM-61 and ZEM-30 monitors on a heat pump 97
Figure B10. ZEM-30 single-phase monitor with current transformer 98
Figure B11. TES-32 temperature sensors mounted on the ceiling of a plant room 98
Figure B12. Temperature probes attached to copper pipes 99
Figure B13. Temperature probe being mounted on a steel pipe 99
Figure B14. Outdoor ground and air temperature measurement assembly 100
Figure B15. ZHM-20 M-Bus monitor connected to a Sontex heat meter 101
Figure B16. ZPC-10 pulse counters connected to battery-powered heat meters 101
Figure C1. Orka Central Manager - analysis charting 104
Figure C2. Cumulative value reversal - as logged, and as corrected by data processing software 107
Figure C3. Data editor showing rogue temperature readings selected for removal 107
Figure D1. Site 17 system schematic 109
Figure D2. Heat pump electrical power and output temperature differences for SH and DHW 110
Figure D3. Comparison of estimated thermal power with heat meter readings 111
Figure D4. Carnot effectiveness for SH mode and the estimated values for DHW mode 111
Figure E1. Example calculation of electricity metering uncertainty 114
Figure E2. Energy errors from all temperature sensor mounting tests 115
Figure E3. Energy errors from temperature sensor mounting tests with strap-on and surface sensors only 116
Figure G1. Temperature sensor lookup table errors in TES firmware V2.83 / V2.84 122
Figure G2. Sample temperature sensor calibration certificate 130
Figure H1. Illustration of brine pump behaviour 132
Figure H2. Illustration of buffer pump behaviour 133
Figure H3. Buffer pump characteristics 133
Figure H4. Cumulative heat measured by heat meter and estimated from temperature measurements 134
Figure H5. Auxiliary heater cycle 135
Figure H6. Auxiliary heater calculated power 136
Figure I1. Estimated measurement error for a strap-on temperature sensor 138