1. BPA RTU Winter Operation Presented to: RTUG August 2010 Presented by: Kathryn Hile, The Cadmus Group Howard Reichmuth, New Buildings Institute

2. B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Winter Analysis Overview  Improvements to analysis template  Downloading and organizing data  Fan operation – schedules  Gas pack operation  Heat pump operation  Winter economizing (or cooling)  Additional opportunities  Lessons learned 2

3. B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Winter Sample  45 serviced RTUs –32 at 3 sites in Puget Sound area –13 at 3 sites in Tri-Cities area  4 baseline RTUs in Tri-Cities: serviced spring 2010 3 RTU TypeNumber of Units SubtractionsUnits Analyzed All Electric1 1 Gas Pack34 529 Heat Pump10 0

4. B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Analysis Template Improvements  All winter data in one spreadsheet (at hour level)  Much smaller analysis files  Automation with SAS and VBA  Time series dynamic graph  Both SA min and SA max plotted in time series 4

5. B O N N E V I L L E P O W E R A D M I N I S T R A T I O N 5 Downloading and Cleaning Data HOBOlink Excel Visual Basic SAS

6. B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Data Preparation Process  Download zip file from HOBOlink with data from all HOBOs  Organize by HOBO  Create one file for each HOBO, based on power, one sheet for each two-week period  Import to SAS with keys for CT size, WattNode scale factor, fan low and fan high 6

7. B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Data Preparation  Calculate hourly and daily minimums, maximums, totals and averages  Export to Excel  Only full 24 hour days used to create energy signature  View data in hourly compressor map, dynamic time series and energy signature 7

8. B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Data Collection Issues  Some (not many) sensors failed last winter, and four sites required troubleshooting to fix –Splitters –AC adapter – battery failure  Downloaded data –One site: two units had nonsensical data –One site: three sensors just disappeared from HOBOlink – result of the AT&T upgrades last fall? 8

9. B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Calculating Percent Outside Air 9

10. B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Winter Operation  Schedules – fan ON or AUTO  Fan kW, duty, base load  Typical signatures 10

11. B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Fan Mode = ON  Winter numbers similar to pilot data 11 Winter DataSummer Pilot Post-Servicing Data RTU Fan kWFan DutyBase LoadFan kWFan DutyBase Load RTU6 0.6991% 15.11 0.6588% 13.68 HP15 0.65100% 15.66 0.63100% 15.06 HP17 1.40100% 33.51 1.4887% 30.96 GP5 0.9699% 22.90 0.8796% 20.13 GP6 2.6999% 63.73 2.6399% 62.53 AC10 0.89100% 21.38 0.92100% 22.19 AC6 2.6638% 24.13 2.9425% 17.42 RTU1 1.4999% 35.28 1.4693% 32.82 RTU3 0.93100% 22.35 0.9194% 20.35 RTU6 1.7340% 16.43 1.7335% 14.43

12. B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Fan Mode = AUTO  Small sample  Fan kW very close; fan duty and base load differed 12 Winter DataSummer Pilot Post-Servicing Data RTU Fan kWFan DutyBase LoadFan kWFan DutyBase Load RTU5 1.8476% 33.48 2.1285% 43.40 RTU3 2.065% 2.68 2.0128% 13.50 HP2 0.608% 1.20 0.69100% 16.45 GP7 1.2826% 7.86 1.2961% 18.71 GP8 1.352% 0.76 1.2314% 4.07 AC9 1.225% 1.46 1.22100% 29.31

13. B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Gas Pack Signatures  24 of 32 energy signatures were as expected  8 needed more investigation to understand performance 13

14. B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Gas Pack Typical Signature 1 14  Operates same set schedule each day

15. B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Gas Pack Compressor Map  Same RTU as previous slide 15

16. B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Gas Pack Time Series 16

17. B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Gas Pack Typical Signature 2 17  Operates slightly longer at lower temperatures

18. B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Compressor Map  Same RTU, compressor map 18

19. B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Gas Pack Typical Signature 3 19  Two signatures – Monday – Saturday, and Sunday  Unit may have reached setback temperatures when average daily temperatures below 40

20. B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Gas Pack Findings  Fan power calculated this winter was close to metered pilot data in almost all cases  Fan duty was close to metered pilot data in units with fan scheduled ON  Fan duty and base load were difficult to predict from summer metered data when fan ran in AUTO mode 20

21. B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Winter Heat Pump Operation  Heat pumps were trickier  Smaller sample, all at a notorious site  Units served either offices or fabrication (manufacturing) spaces  Four units did not have economizers 21

22. B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Heat Pump Typical Operation  Energy increases as temperatures decrease  Steeper slope than for cooling 22

23. B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Heat Pump Compressor Map  Same unit as previous slide 23

24. B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Heat Pump Time Series 24

25. B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Heat Pump Findings  Typical heat pumps will have a second sloped line  Need summer data (spring was not warm enough) to connect winter and summer usage  Will use that to calculate and predict total annual energy use, not just cooling and fan 25

26. B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Winter Economizing  Some units modulate dampers to take advantage of free cooling.  SA min and SA max track OAT  Three speed fan? 26

27. B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Heating to Economizing  Fan operates at different power when heating or economizing 27

28. B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Atypical Performance  Balance point below the range of monitored temperatures  Cooling at low temperatures  Units serving the same space  Two units with bad data 28

29. B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Low Balance Point 29

30. B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Cooling at Low Temperatures  Mechanical cooling at 25 degrees 30

31. B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Cooling at Low Temperatures 31

32. B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Heating a.m., Cooling p.m.  Two different max kW, at 3.5 kW, cooling (SA min at 55) and heating 4.5 kW (SA max at 90) 32

33. B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Someone’s Been in my RTU… 33

34. B O N N E V I L L E P O W E R A D M I N I S T R A T I O N …Twice! 34

35. B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Economizer Findings  Cooling at temperatures below 40 degrees. Why? Controls? Or dampers didn’t modulate because broken? Bad sensor? Comments? Significant savings opportunity?  Cooling in the 50-60 degree F. Could economizer changeover temperature be increased for additional savings?  Winter is a good (better than summer?) candidate for economizer savings 35

36. B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Preliminary Annual Signature  Winter: –Standard, flat gas pack –Standard, sloped – but could we just take an average and keep slope at 0? –Gas pack with two occupancy schedules –Heat pump – is this signature messier than it would be during summer cooling? TBD.  Atypical. 36

37. B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Ex: AC w/Elect Resistance Heating 37

38. B O N N E V I L L E P O W E R A D M I N I S T R A T I O N AC Compressor Map 38

39. B O N N E V I L L E P O W E R A D M I N I S T R A T I O N AC Time Series 39

40. B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Next Steps in Research  Draft annualized savings methodology with separate characterizations of annual operation for summer and winter  Data block interval analysis  Recommendations regarding fan schedule persistence  Additional persistence analysis  Measure life implications from the data  Updated M&V protocol recommendations 40

41. B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Web-Enabled Thermostats  Test the web-enabled thermostat as an M&V tool as a substitute for data-loggers –Data-friendliness? –How complete is it? –What does it look like?  Use the current analysis protocol and modify it for these data 41