Up on the Roof Up on the roof I've found a paradise that's trouble proof, up on the roof. C. King/G. Goffin 1962

Transcription

1 CEE Winter Meeting January 12 14, 2010 San Francisco Up on the Roof Up on the roof I've found a paradise that's trouble proof, up on the roof. C. King/G. Goffin 1962

2 Rooftop Unit World Perfect manufacturer designs Perfect manufacturing Perfect sizing Perfect installation Perfect controls Perfect operation Perfect maintenance

3 O&M Filter

4 Where Filters Go to Die

5 PNW RTU Market Size [2006] 320,000 units 5 ton predominates 27,000 new units annually 16,000+ replacement 11,000+ in new construction STATE SHARES 41% 39% 12% 8%

6 Savings in MWa th Power Plan New NR Retro Total Package Roof Top Optimization and Repair Demand Control Ventilation Total TRC Levelized Cost: Mostly $10 to $50 per MWh

7 Rooftop Unit Working Group Time Line NEEA RTF Phase I 2004 RTF Phase II RTF Phase III Pilot Field Work Inconclusive savings Identified potential deadband issues Not ripe for Market Transformation Secondary Source Review Frequency of Problems Scope Next Phase Test Protocol to Measure Savings Large Field Test Goal: Prov Deemed, Deemed Calc/MV Protocol Scope Next Phase Lab Testing Limited Field Test Honeywell Redesign Develop Protocol to Measure Savings Scope Next Phase

8 Related RTU Activities Northwest Energy Efficiency Alliance HVAC contractor training Regionwide RTU program support Emerging Technology program Bonneville Power Administration HVAC Emerging Technologies Premium Ventilation Package R&D California Activities Western HVAC Performance Alliance CEC PIER RTU FDD 2 projects HVAC EM&V Results Charge/Airflow Correction [RCA]

9 PNW RTU Count 236 Metered Avista = 12 side by side metered [2 pair in place] Bonneville Power Administration RTU Pilot = 161 metered 12 months] Energy Trust of Oregon = 94 serviced/13 metered Idaho Power = 9 metered 12 months] Puget Sound Energy = 41 metered

10 BPA Pilot Evaluation Elements Pilot evaluation approach: Measure cooling and fan energy use at individual RTU level Larger sample size Two week pre/post metering with annualization Energy signature (kwh and OA temperature) and TMY3 weather data to annualize cooling and fan energy savings Compare metered savings to estimated savings Report results and lessons learned to improve estimation, measurement, and realization of energy savings Recommend improvements to direct BPA s 2010 Performance Tested HVAC program

11 Performance Tested HVAC Thermostat measures Replacement Setpoint and schedule changes Economizer measures Economizer commissioning Setpoint changes Fixing dampers Replacing or repairing broken parts Minimum and maximum ventilation adjustment Refrigeration cycle measures Condenser and evaporator coil cleaning System airflow adjustment refrigerant charge adjustment

12 Premium Service Packages Each RTU received a package of measures Basic Diagnostic package (A): Other packages: B (basic diagnostics plus fix damper) C (basic diagnostics plus new thermostat) D (basic diagnostics plus new controller)

13 BPA On-Site Data Collection 161 RTUs metered Minimum two weeks baseline and post-servicing One-minute data Site characteristics recorded On-site data collection HOBO U30 loggers/cda Basic metering package: Total unit power Outside air temperature/rh Modified basic package: Supply air temperature Y-1 call for cooling Full package: Return air temperature Supply air temperature Mixed air temperature

14 How many people does it take to screw in a rooftop unit? = 36

15 BPA Sample Distribution 15

16 Average savings by unit age BPA Metered Savings Average savings by RTU type Average savings by existing servicing contract

17 Savings Algorithm Energy signature: used with TMY3 data to annualize energy Horizontal line = fan energy Sloped line = fan + compressor energy Balance point = intersection of horizontal and sloped lines 17

18 BPA Metered Savings Total cooling and fan energy savings Emerging Energy 18

19 BPA Metered Savings Compressor and fan savings (kwh/ton) 19

20 BPA Thermostat Measure Savings Operating schedules Average savings for 30 RTUs: 3,307 kwh Average savings 7 tons and greater: 5,198 kwh 83% of the units realized savings Maximum savings: 15,408 kwh

21 Idaho Power RTU Results

22 RTU Reality TV: ETO BAU Site Sample 3 HVAC units with economizers, 1 functional; 2 units did not have 2 stage controls Outside ventilation disabled on 2 of 3 units None of the businesses had appropriate scheduling Noticeable air leaks around roof curbs new issue or helps with minimum air flow? 22

23 Case Pre- retrofit kwh ETO Summary of Electric Savings Post- retrofit kwh KWh Saved % Saved Treatment Dentist Back 5,826 1,645 4,181 72% New economizer, new thermostat, implemented setback Dentist Front 7,827 2,716 5,112 65% New economizer, new thermostat, implemented setback Pizza Kitchen 3,192 1,159 2,033 64% New economizer, new thermostat, implemented setback Sandwich Shop 15,131 6,432 8,699 57% New economizer, new thermostat, implemented setback Shipping Store 2,949 1,255 1,694 57% New economizer, new thermostat, implemented setback Pub 5,716 3,381 2,334 41% Restored non-functioning economizer, set changeover to 63 deg, new thermostat, implemented setback Office 4,658 3, % New economizer, existing thermostat, implemented setback Pizza Front 12,941 10,632 2,309 18% No economizer, new thermostat, implemented setback Vet Front 3,561 3, % Restored non-functioning economizer, set changeover to 63 deg, new thermostat, implemented setback Hair Salon 4,026 3, % New economizer, new thermostat, implemented setback, increased ventilation Retail Front 2,421 2, % Existing economizer was functional, set changeover to 63 deg, new thermostat, implemented setback Vet Back 4,231 4, % New economizer, new thermostat but no setback Retail Back % Cleaning but no other treatment, unit is seldom in use Average All units (15 cases) 5,600 3,455 2,145 38% 2,074 37% 23

24 2009 RTU Savings Results What We Know

25 2009 RTU Savings Results What We Know 2 Bonneville ETO Idaho Power PSE

26 2009 RTU Savings Results What We Still Need To Know

27 PNW RTU Results Database Summary Site Summary Site ID RTU ID Weather data Annual kwh pre Annual kwh post Compressor stages Compressor max duty (frac of full load) Economizer (y/n) Monitoring level Pre and Post Service Summary Fan kw Fan duty (frac of full load) Baseload kwh/day Balance point temp Slope kwh/day/degf 80 deg F, Stage 1&2 kw Compressor trigger degf

28 Overview of Air Care + Energy Savings: Overview of average energy savings per measure per unit: * By Measure: Measures rebated kwh total kw total Therms total Average kwh/unit Average kwh/ton Average Therms Basic Package Without Economizer 5, , Basic Package With Economizer 3,424 7,455, , Economizer Refurbish 699 1,578, , Economizer Control Package , , Refrigerant Pre-Test 7, Refrigerant/Airflow (1 Comp.) 3,446 4,017,692 1, , Refrigerant/Airflow (2 Comp.) 1,739 3,418,919 1, , Thermostat Modification 1,685 1,551, , Thermostat Replacement 206 1,075, ,037 5, Totals by Measure: 23,912 19,853,767 2,551 32,529 * kwh savings based on results in prior California IOU Air Care Plus programs by PECI. * Average unit size: 7.62 tons (except refrigeration: 4.7 tons single compressor; 12.6 tons multiple compressor). * Energy savings per measure are deemed and supported by approved workpapers, and Avoided Cost Calculator Workbook (E3) calculations. * Actual energy savings will vary with each customer s situation, including but not limited to the actual measures or equipment installed, building construction, customer operation, age of existing equipment, and location. 28

29 2009 PNW RTU Outcomes Critical Body of Knowledge being assembled Measurement & analysis continuing >12 months Results database being established for additional analysis Provisional deemed savings potential

30 Advanced Rooftop Unit (ARTU) Significant improvements Outdoor air control Economizer reliability Self diagnostics Fault tolerant design Not tested in EER/SEER RTU EUI ARTU EUI CDD65 Energy Use Index, kwh/sq.ft ,000 4,500 4,000 3,500 3,000 2,500 2,000 1,500 1, Cooling Degree Days, base 65ºF San Diego Sacramento Palm Springs Total benefits from $600 to $830 annually. Estimated cost for 36 ARTU features was $4,100 (5 ton RTU) Simple payback between 4.9 and 6.9 years

31 RTU Efficiency Measures that are NOT measured by EER, SEER & IEER Economizer and damper effectiveness Damper seals Demand Controlled Ventilation (DCV) Variable speed fan; low speed during idle Ventilation lockout during warmup Evaporative pre cooling of condenser

32 Premium Ventilation Package Start with a Western Premium Economizer Upgrade the Economizer module with DCV capable economizer control module CO 2 Sensor; Min air set to 0% = leakage Add variable speed fan motor Full (or near full) speed in heating or cooling Low (30%) speed in idle mode Field testing currently underway in Pacific Northwest

33 Regional Savings Premium Ventilation HVAC kwh per 1000 square feet 12,000 10,000 8,000 6,000 4,000 2,000 Remaining Fan & Aux Remaining Cooling Remaining Heating Evap pre-cool VSD fan DCV Integrated Economizer warmup cycle Strip Heat lockout Optimum Start Total ECM Savings 0 Phoenix AZ Sac'to CA Eugene OR Boise ID Burl'ton VT Chicago IL Memphis TN Houston TX Base Total HVAC

34 Economizer Control Hysteresis Problem Earlier tune up adjustments to existing packaged systems did not achieve expected savings Two investigations showed economizers did not work as expected even after proper adjustment procedures were followed A study organized by Northwest Power and Conservation Council Regional Technical Forum For the most common economizer controller and sensor A wide hysteresis [6 10degF] was found in 2008 bench testing; manufacturer concurred Economizing will not occur unless night time temperatures fall to the low set point, which may not happen

35 Sensor Testing Laboratory

36 Manufacturer Cooperated in Replacement Manufacturer has redesigned dry bulb sensor: Honeywell C7660 replaces C7650 Sensor controls controller [W7459] Digital functionality New sensor will minimize the control deadband and improve precision. Can be retrofit to existing controllers same form factor Approx. $4 incremental cost

37 Outside Air Sensor Placement

38 Western HVAC Performance Alliance CPUC CLTSEEP: Transform the HVAC Industry Irvine Company Owners, Facility Mgrs, Property Mgrs NATE Training/Certification Williams Comfort HVAC Manufacturer Mechanical Air Service NonResidential Contractor CALBO Local Building Code Officials HARDI Distributor Associations ACCA Contractor Associations Lennox Industries HVAC Manufacturers Bay Area SMACNA Labor Aire Rite AC&Refriger. NonResidential Contractor RSES Educators, Trainers AHRI HVAC Manufacturer Associations CEC State Government S MUD Publicly Owned Utilities TruTech Tools Controls (Mfg, Distributors) IHACI Contractor Association Beutler Corporation Residential Contractor 3EInternational Consultant Pacific Gas & Electric Southern California Edison Sempra Utilities

39 Total US Cooling Solution CTU Country Top Unit 50 ZILLON 726

40 PNW Rooftop Working Group ongoing/rtug/default.htm Rooftop Unit Pilot Servicing Program Summer 2009 Monitoring Final Report BPA RTU Puget Sound Pilot 2009 NEEC