Electric “Grid” Savings and Non-Electric Benefits for Residential HVAC-effected UES Measures Regional Technical Forum March 20, 2013

Overview For residential measures that effect heating and cooling usage: – RTF electric savings estimates should be reliable from an electric utility planning perspective (i.e. “Grid Savings”). Measured Savings are considered reliable. – There appear to be non-electric benefits the RTF can account for in its cost-effectiveness tests. Measured Savings < Modeled Savings. Primary questions: – Is the following proposed framework for “Grid Savings” and NEB’s correct? – How should RTF monetize non-electric benefits? 2

Framework 3

4 Modeled Savings (“The Whole Pie”) Definition: Estimated electric energy savings; based on physics (lower UA = lower heating energy use). Example: Model assumes 100% electrically heated houses and “typical” usage.

5 Model Correction Definition: Adjustment to modeled savings to account for non-typical usage. Example: Partial Occupancy; occupants are away for the winter months and leave t-stat at a very low setting.

6 Measured Electric Savings (a.k.a “Grid Savings”) Definition: Electric energy savings for the population, measured through submetering or billing studies.

7 Non-Electric Benefits Definition: Portion of the Modeled Savings that apply to the following two non-electric components: Fuel Savings (Non-electric) -Example: Occupant stops using their wood stove in the efficient-case, in favor of the electric heating system. -Example: Occupant continues using their wood stove, but uses less wood because of the lower house heat loss. Increased Comfort -Example: Occupants operate their house at a warmer (winter) and cooler (summer) temperature in the efficient- case.

8 Not to Scale – These will vary by program, region, modeling method, etc.

Examples DHP Weatherization 9

IDItemSource/MethodHeating Zone 1 Heating Zone 3 A Modeled Savings Metering Study 4000 IDItemSource/MethodHeating Zone 1 Heating Zone 3 A Modeled Savings Metering Study 4000 B Measured Electric Savings Billing StudyAll Sites IDItemSource/MethodHeating Zone 1 Heating Zone 3 A Modeled Savings Metering Study 4000 B Measured Electric Savings Billing StudyAll Sites C Measured Electric Savings + Non-electric Fuel Savings Billing Study Filtered for No Supplemental Fuel IDItemSource/MethodHeating Zone 1 Heating Zone 3 A Modeled Savings Metering Study 4000 B Measured Electric Savings Billing StudyAll Sites C Measured Electric Savings + Non-electric Fuel Savings Billing Study Filtered for No Supplemental Fuel Non- electric Benefits Fuel SavingsC – B IDItemSource/MethodHeating Zone 1 Heating Zone 3 A Modeled Savings Metering Study 4000 B Measured Electric Savings Billing StudyAll Sites C Measured Electric Savings + Non-electric Fuel Savings Billing Study Filtered for No Supplemental Fuel Non- electric Benefits Fuel SavingsC – B Increased ComfortA - C Using DHP as an Example 10 Grid Savings (kWh) Non-Electric Benefits (need to monetize) Notes: 1. All values in kWh/yr. 2. Values and method are for example only – we’ll discuss DHP measure specifics later. 3. Model Correction is assumed to be 0 kWh/yr based on design of Metering Study.

IDItemSource/Method AModeled Savings SEEM runs calibrated to RBSA “post” t-stat setting; houses with “good” electric & gas bills only T-stat: 68°F pre & post BModeled Savings – Increased Comfort SEEM runs calibrated to RBSA “pre” and “post” t-stat setting; houses with “good” electric & gas bills only Tstat: 65°F pre 68°F post CModel Correction Rough estimate based on RBSA data % of houses with electric & gas heat only and with poor PRISM R-square DNEB Fuel Savings Rough estimate based on 2 sources i. RBSA: % of heat supplied by “other” fuels in electric heat homes ii. DHP: % of fuel savings in the DHP measure Measured Electric SavingsB – C – D Non Electric Benefits Fuel SavingsD IDItemSource/Method AModeled Savings SEEM runs calibrated to RBSA “post” t-stat setting; houses with “good” electric & gas bills only T-stat: 68°F pre & post BModeled Savings – Increased Comfort SEEM runs calibrated to RBSA “pre” and “post” t-stat setting; houses with “good” electric & gas bills only Tstat: 65°F pre 68°F post IDItemSource/Method AModeled Savings SEEM runs calibrated to RBSA “post” t-stat setting; houses with “good” electric & gas bills only T-stat: 68°F pre & post BModeled Savings – Increased Comfort SEEM runs calibrated to RBSA “pre” and “post” t-stat setting; houses with “good” electric & gas bills only Tstat: 65°F pre 68°F post CModel Correction Rough estimate based on RBSA data % of houses with electric & gas heat only and with poor PRISM R-square IDItemSource/Method AModeled Savings SEEM runs calibrated to RBSA “post” t-stat setting; houses with “good” electric & gas bills only T-stat: 68°F pre & post BModeled Savings – Increased Comfort SEEM runs calibrated to RBSA “pre” and “post” t-stat setting; houses with “good” electric & gas bills only Tstat: 65°F pre 68°F post CModel Correction Rough estimate based on RBSA data % of houses with electric & gas heat only and with poor PRISM R-square DNEB Fuel Savings Rough estimate based on 2 sources i. RBSA: % of heat supplied by “other” fuels in electric heat homes ii. DHP: % of fuel savings in the DHP measure IDItemSource/Method AModeled Savings SEEM runs calibrated to RBSA “post” t-stat setting; houses with “good” electric & gas bills only T-stat: 68°F pre & post BModeled Savings – Increased Comfort SEEM runs calibrated to RBSA “pre” and “post” t-stat setting; houses with “good” electric & gas bills only Tstat: 65°F pre 68°F post CModel Correction Rough estimate based on RBSA data % of houses with electric & gas heat only and with poor PRISM R-square DNEB Fuel Savings Rough estimate based on 2 sources i. RBSA: % of heat supplied by “other” fuels in electric heat homes ii. DHP: % of fuel savings in the DHP measure Measured Electric SavingsB – C – D Non Electric Benefits Fuel SavingsD Increased ComfortA – B IDItemSource/Method AModeled Savings SEEM runs calibrated to RBSA “post” t-stat setting; houses with “good” electric & gas bills only T-stat: 68°F pre & post BModeled Savings – Increased Comfort SEEM runs calibrated to RBSA “pre” and “post” t-stat setting; houses with “good” electric & gas bills only Tstat: 65°F pre 68°F post CModel Correction Rough estimate based on RBSA data % of houses with electric & gas heat only and with poor PRISM R-square DNEB Fuel Savings Rough estimate based on 2 sources i. RBSA: % of heat supplied by “other” fuels in electric heat homes ii. DHP: % of fuel savings in the DHP measure Measured Electric SavingsB – C – D Using Weatherization as an Example 11 Note: This method is shown for illustration of the framework only; it has not been reviewed by the RTF and may not meet the RTF’s guidelines. IDItemSource/Method AModeled Savings SEEM runs calibrated to RBSA “post” t-stat setting; houses with “good” electric & gas bills only T-stat: 68°F pre & post

Next Steps In both examples, Non-Electric Benefits are quantified in kWh’s. We need to then monetize the Non-Electric Benefits 12

ProCost Inputs 13 Data Source(s) kWh/$ Conversion

How to Monetize the Non-Electric benefits? Option 1: Convert each Non-Electric Benefits into Dollars – Non-Electric Fuel Savings Convert kWh savings to cords of wood savings to dollar savings – Issue: Many assumptions needed (Btu/cord; efficiency of stove, $/cord, pollution benefit, etc.) – Increased Comfort Value at the retail cost of electricity – Occupant chose to pay for more electricity, so value of comfort should be at least equivalent to the price of electricity, if not more. – Issue: Split between Increased Comfort and Non-Electric Fuel Savings is unknown. Option 2: Value both Non-Electric Benefits at the retail cost of electricity – Same logic as for Increased Comfort above – The “many assumptions” for converting kWh savings to cords of wood to dollar savings would likely be “calibrated” to this value. (Value of wood calibrated to be no lower than value of electricity.) 14

Decisions 1.Adopt the presented framework for quantifying Measured Electric Savings and NEB’s? – Current Method NEB’s are not included in the cost-effectiveness test. – Proposed Method Quantify and Monetize NEB’s according to framework. Include in cost-effectiveness test. 2.How to Monetize NEB’s? – Option 1: Convert each Non-Electric Benefits into Dollars; or – Option 2: Value both Non-Electric Benefits at the retail cost of electricity – Other Options 15

Background Slides 16

Related slides from the January 2014 RTF Meeting (“SEEM 94 Calibration to RBSA Data” Presentation) 17