Transformer De-Energizing & Dairy Plate Heat Exchanger

1. Transformer De-Energizing &Dairy Plate Heat Exchanger Standard Protocol Proposal Presentation to the RTF February 20, 2013

2. Protocol History • Adopted “deemed calculator” versions in 2002 • Savings Guidelines adopted 6/1/11 which removed deemed calculator category • Cascade Energy awarded contract in 2012 to convert deemed calculators to Guidelines compliant Standard Protocols • Presented draft protocols at Oct. & Nov. 2012 RTF meetings

3. Protocol History • Received feedback at meetings on likely path • Small Saver recommended at Nov. RTF meeting for both protocols • Tabled decisions until updated Savings Guidelines were adopted to allow for Small Saver Standard Protocols • Mike Baker reviewed for compliance with updated 12/11/12 Savings Guidelines • Presenting revised proposal today

4. Standard Protocol Transformer De-Energizing

5. Protocol Summary • Best Practice Savings Estimate • Determine no-load loss by measuring the power of the transformer when it is energized, but does not have an electrical load. • Collect transformer nameplate data (type, voltage, phase, capacity rating). • Determine the number of hours per year the transformer is de-energized based on utility record of date(s) of de-energization and date(s) of re-energization. • Savings are calculated as the product of hours of de-energization and no load power draw. • Savings are to be determined in this manner each year the transformer is de-energized. • Simplest Reliable Savings Estimate • Determine no-load loss by: • Default rated capacity by utilizing default NEMA TP-1 transformer efficiency ratings • Alternately, use manufacturer published no-load loss or power measurement • Remaining steps follow the Best Practice.

6. RTF feedback from last meeting • Using NEMA tables vs. field data collection • Field data collection is costly, and savings are not justified given the expense • Regionally representative default table would be better however not worth the cost to obtain given small savings • Only two utilities run xfmr de-energizing programs • Keep NEMA table as-is and realize protocol is a small saver for the region

7. Protocol changes since November • Cleaned up verbiage to clarify definitions, delivery verification and data collection characteristics • Biggest change is restructuring of simplest reliable method to use NEMA default table • Previously had manufacturer rating as primary collection method, default table as secondary • Guidelines require alternate methods to be of sufficient or better reliability

8. RTF Proposed Motion: “I _________ move that the RTF approve the Transformer De-Energizing Standard Protocol and assign it to a “Small Saver” category with “Active” status and a sunset date of February 20, 2017.”

9. Standard Protocol Dairy heat exchanger

10. Process Flow Diagram T T = temperature measurement T

11. Measure Definition

12. Simplest Reliable Method Same equations as Best Practice, different data collection

13. Simplest Reliable method • can be impossible to measure. • Easier to measure water heat gain rate than milk heat lossfor baseline and post water-cooled HXR. • Need to measure transfer pump runtime per quantity of milk • Same equations for post HXR Portion removed by water Total heat rejection

14. RTF feedback from last meeting • Added heat from transfer pump assumed to be trivial; effect not included in calculation • Specify that measurements are taken close to HX to avoid varying system configurations • COP sensitivity analysis performed • COP assumptions reasonably accurate across wide range of expected suction/discharge temps • Develop COP lookup tables for other common refrigerants

15. Protocol changes since November • Cleaned up verbiage to clarify definitions, delivery verification and data collection characteristics • Removed New Construction from eligible projects due to missing standard practice baseline • Added language directing practitioner to measure water temperatures as close as possible to the heat exchanger • Made all refrigerants eligible for the protocol, with all refrigerants other than R-22 and R-507 assumed to have the same COP as R-404a

16. Protocol changes since November • Added supporting documentation to capture “non-protocol specific” analysis • Biggest change is restructuring of simplest reliable method in protocol • Previously had temp probe measurement as primary collection method • Guidelines require alternate methods to be of sufficient or better reliability

17. RTF Proposed Motion: “I _________ move that the RTF approve the Dairy Heat Exchanger Standard Protocol and assign it to a “Small Saver” category with “Active” status and a sunset date of February 20, 2017.”

18. COP Sensitivity Analysis • COP dependent on refrigerant, suction & discharge pressures • Calculator COP assumptions: • Suction temp = 20 °F below storage temp • Typical discharge pressure = 200 psig • Pressure cut-in/cut-out setpoints unchanged if change refrigerant • i.e. 200 psig discharge pressure remains typical for all 3 refrigerants • Refrigerant is known (R-22, R-404, R-507) • Table compares energy savings with fluctuating COP (best practice) vs. simplest reliable method. • Conclusion  COP assumptions are reasonably accurate across a wide range of suction/discharge pressures