EER Analysis Results Regional Technical Forum March 18, 2014

Energy Efficiency Ratio (EER) Definition Given by ASHRAE as “…a ratio of the cooling capacity in Btu/h to the power input values in watts at any given set of Rating Conditions” – Expressed in Btu/(W-h) Signifies the amount of power needed to remove heat from a space Used as an interaction parameter in grocery UES measures that reduce case loads – Exception: Primary factor for direct refrigeration system reduction (i.e. Floating Head Pressure Control) 2

Energy Efficiency Ratio (EER) Use EER is a single point estimate of efficiency – Usually given at AHRI standards: 80°F db/67°F wb – SEER looks at system efficiency over a given season Site conditions are likely different than AHRI DOE2.2R calculates an “annual average EER” value to arrive at seasonal efficiency RTF uses this value in annual savings calcs for refrigeration measures 3

What do we reliably know about EER? It is not easily measured in the field Multiple variables exist among a population – Large sample likely needed to normalize results Cost/site to obtain accurate measurements is large Would results from field monitoring be more reliable than modeling? – Or more importantly, when does it matter? 4

What do we reliably know about the impact on UES measures? Tasked PECI to perform a sensitivity analysis – Task 1 – Identify possible EER range – Task 2 – Perform sensitivity analysis on measures – Task 3 – Define a single EER value for LT and MT Use EnergySmart Grocer (ESG) data to determine representative refrigeration systems Determine which measures have savings which vary significantly with EER 5

Subcommittee Process Grocery Subcommittee discussed all tasks and draft findings over and webinar Grocery Subcommittee General agreement on analysis approach and results 6 AttendeesSeptember 26March 6 Bill Koran (Northwrite) x Michele Friedrich (SMUD) xx Mike Baker (SBW) x Josh Rushton (RTF) xx James Russell (PECI) x Ben Wright (PECI) x Christopher Rogers (PECI) xx Charlie Grist (NWPCC) xx Nick O'Neil (NWPCC) xx Eric Mullendore (PECI) x Jamie Anthony (BPA) x Andie Baker x

EER Sensitivity Analysis Results Determine likely range of EER values – High/Low values represent AHRI range – Median values found in ESG (used as base EER) 7 EER Range for Grocery Stores System TemperatureBase EERLowHigh Medium Temperature Low Temperature

Sensitivity Analysis Results - MT 8

Sensitivity Analysis Results - LT 9

EER Sensitivity Analysis Results Results show minimal impact on savings for component reduction measures despite a wide range of possible EER values – Ex. LED lighting, Anti-Sweat Heater Controls Large variation for system reduction measures – Ex. Autoclosers, Strip Curtains, Gaskets Subcommittee agreed range presented was representative of field conditions – Wanted to define EER further for UES measures 10

EER Definition Work PECI to use ESG audit data to develop representative LT & MT refrigeration systems Representative systems from ESG mapped to eQuest to generate hourly reports – Grocery subcommittee reviewed mapping – No substantive changes requested Hourly reports used to generate annual EER value for use in UES calculations 11

EER Definition Work – Draft Results 12 Grocery System Configurations Annual Average EER Value (Btu/hr-W) Average EER of System Configuration (Btu/hr-W) Average EER of Temperature (Btu/hr-W) Weighted Average EER for Temperature * (Btu/hr-W) Medium Temperature Multiplex Medium Temperature Standalone Low Temperature Multiplex Low Temperature Standalone * Weightings developed using grocery store audit data; 75% multiplex, 25% standalone

EER Definition Review Comments Subcommittee agreed with general methodology used Had a comment to use evaporator load to calculator EER instead of condenser load – Likely to results in about 15% lower EER value – Less of an impact on measure savings Will require minor work to eQuest outputs Not available in time for March RTF meeting PECI to develop and present findings to group 13

EER Definition Proposal Subcommittee recommends including results table and instructions for use in RTF Standard Information Workbook Legacy measures – Use results to update All small savers to use results of analysis New measures – Use sensitivity analysis to determine EER impact – Values acceptable to use if interaction is +/-10% 14

Staff Recommendation Reference the EER analysis in the SIW Update final table with values from PECI – Grocery subcommittee will review results Use to update legacy UES measures – Only where EER contributes minimally to savings or the measure is a small saver Use table on applicable future measures after sensitivity analysis has been performed 15

Proposed Decision “I _______________ move that the RTF approve the EER analysis as presented and, following a diligent review by the Grocery Subcommittee, include the final EER results table in future updates of the Standard Information Workbook for use in UES measure assessments.” 16