Agricultural Irrigation Pump Variable Frequency Drive Provisional Standard Protocol Proposal Regional Technical Forum April 16, 2013

Protocol Summary Eligibility[see Protocol document] BaselineSingle speed pump for irrigation without VFD UpgradeInstall VFD set to automatic control mode, remove or disable baseline control mechanism Best Practice Savings Estimate 1.Collect three years of pre metering and one year of post metering on individually metered pump motors or on circuits where upgraded motor load is easily disaggregated (e.g., sharing circuit with small electric motors for center pivot, sharing circuit with another pump with known operating hours). 2.Adjust annual baseline kWh values to reflect hardware measures on the irrigation system, for all years prior to the hardware measure implementation. 3.Determine average annual kWh pre and post installation. 4.Savings = [Average Annual Baseline kWh] – [Post Installation Average Annual Baseline kWh] Simplest Reliable Savings Estimate 1.Pre metering for three years 2.Savings = [Average Annual Baseline kWh] x [Average Project Savings %]

Available Best Practice Data Utility billing data from pre and post metered pumps. – Two years of pre-VFD data (average annual kWh provided) – One year of post-VFD data Data disposition – 95 projects at 7 utilities – Dates, installed between February 2010 and June – Motor Size, 30 HP to 500 HP – Project Cost, $5,000 to $79,000 3

Available Best Practice Data (cont) Analysis – For each site, computed the annual savings and the savings as a percentage of baseline kWh. – Considered the unweighted (all projects equal) and weighted (by baseline kWh) average savings percentage. 4 Savings as a Percentage of Baseline kWh unweightedweighted estimate27%25% n95 90% confidence17%27% lower bound23%18% upper bound32%

Available Best Practice Data (cont) 5

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Discussion Since precision at 90% confidence is greater than 10%, the protocol should be categorized as “Provisional”. Possible measure interaction in dataset (e.g. irrigation hardware measures). – Proposed protocols allow for additional measures on same metered circuit if estimated savings are accounted for. Proposed protocols allow for multiple equipment on meter and rely on operator estimation of operating hours for significant equipment. Year-to-year variations in operating conditions (crop type, acreage, weather, etc.) are not accounted for at any individual site. – This “measurement error” is expected to average to zero for the population. – Crop type and acreage will be collected during provisional period. Eligibility limited to 30 to 500 HP motors, based on dataset. Can this be extended to 20 HP motors? The percent savings may reduce over time. – This will be something to watch for when making the determination to go to “Proven” category. 7

RTF Proposed Motion: “I _________ move that the RTF approve the Agricultural Irrigation Pump Motor Variable Frequency Drive Standard Protocol in the “Provisional” category, with “Active” status, and a sunset date of April, 2018.”