Manufactured Homes Calibration: Existing and New Homes Mohit Singh-Chhabra & Josh Rushton RTF MH Calibration Subcommittee February 27, 2015

Objective Seeking subcommittee feedback on analysis plan intended to compare RBSA-based calibration to actual program data 2

Background Three “Oregon trail” modifications to pure-physics savings estimates: – Calibration Phase I: Align SEEM output with billing data for RBSA homes with "clean" heating energy data (clean = good VBDD fit and no evidence of off-grid heat) – Calibration Phase II: Account for nonelectric fuel types (gas and "wood") and poor VBDD fits – Long-term interaction Option 3: Account for interactions with measures likely to be installed later End result: Lower savings than we’re used to seeing RTF direction: Staff should reality-check against actual program data 3

Proposed Path(s) for Existing Homes Plan to test “Oregon trail” estimation procedure by investigating two parallel paths: Savings: Compare bottom-line “Oregon trail” estimates to actual program/billing data Phase I: Compare RBSA-based calibration curve to pre-/post- program data 4

Existing MH: Savings Comparison Compare “Oregon trail” savings to verified program savings Only trying to test “right-on-average” – Expect to test broad measure groups (e.g., ceiling / other) – No finer-grained tests (e.g., windows / walls /… / ducts) Idaho Power program data – 140 MHs (≈105 with 1+ yrs. pre-bills and 1+ yrs. post-bills) – Includes detailed audit data (pre/post shell & equipment specs, blower door results, …) Supplemental Sources: – EWEB evaluation report ~1998 – Evaluation reports form CO and the Midwest. 5

Existing Homes: Savings Comparison (Contd.) Idaho Power audit data includes MH HVAC and weatherization measure specs. Enables us to… Assign “Oregon Trail” savings to program measures. How do these compare to VBDD-based estimates? Check what measures are being implemented. How do Wx’d homes compare to our full measure package assumptions Calculate savings estimates from package of measures using VBDD Comments/questions on this part of the plan? 6

Existing Homes: Phase I Focus on single (critical) step in “Oregon Trail” Phase I adjustments based on observed trend in differences SEEM.69 – VBDD.kWh Trend currently based on observational cross-section of regional homes (RBSA) Propose to use ID Power data to calculate VBDD and SEEM.69 for pre-/post- sample Is existing trend consistent with pre-/post- sample? Side note: Need to standardize SEEM.69 same as before. 7

Existing Homes: Phase I Starting point: Add new observations to this graph Analysis to depend on what we see Is the existing trend consistent with program data? 8 Remember this? Comments, questions, other ideas?

New Homes Calibration Staff have received feedback that MH New Construction calibration requires dedicated analysis – as opposed to extrapolating existing construction calibration to fit new construction homes CAT have reached out for data – Efforts concentrated on existing homes calibration first Not sure what this effort should look like 9

New Homes Calibration (Contd.) Available data: NEEM MH Billing and Field Data Analysis – 89 homes in final sample across all 4 states – Billing data studied for 78 homes – Analysis of building characteristics Mean values and distribution of all relevant building properties (Similar to RBSA report) – Raw data sets may not be available Super Good Cents MH Field Data – 101 homes with field data; no billing analysis Comments, suggestions? 10