Preliminary Impact Analysis of SCEs 0405 HEES Program

1
Preliminary Impact Analysis of SCEs 04-05 HEES
Program

• Population Regression using Consumption Trend of
  Participants Neighborhoods as Covariates
• John Peterson, Athens Research
• Carol Yin, Yinsight
• CALMAC, October 17, 2007

2
SCEs long standing interest in energy savings
from home audits

• RER study (1997) of SCEs 1993 1995 residential
  audit programs
• Net 1st year savings In Home (433 kWh),
  Telephone (154 kWh), Mail-In (123 kWh)
• Ridge study (2002, on CALMAC.org)
• Net 1st year savings In Home (440 kWh),
  Telephone (185 kWh), Mail-In (123 kWh), Online
  (123 kWh)
• BUT, savings estimates are outdated

3
Benefits of using the ecological consumption
trend

• Consumption related variables arguably relatively
  homogeneous at block group/dwelling level
• Accounts for weather changes and difficulties
  linking weather station data to small areas
• Accounts for economic differences between areas,
  and changes over time within those relatively
  homogenous areas
• Accounts for demographic features, cultural and
  behavioral trends

4
Method

• Models estimated at a gross population level
  whether or not the customer has participated in
  04-05 HEES
• Preliminary analysis does NOT track causal flow
  of savings from recommendation adoptions
• Filtered 04-05 participants on the basis of
• 12 months of pre-audit consumption data, 12
  months of post-audit and post 10 month deadband
  data (others deadbands were tested).
• The ecological consumption trend
• Calculated from calendarized residential
  consumption data from 2002-2007
• Averaged by dwelling type (single family/other)
  within geography (block group/tract/zip) so that
  each participant compared with at least 100
  neighbors
• Ecological consumption data scaled on participant
  by participant basis, so pre-period average
  consumption of participant and neighbors matched.

5
Preliminary Results

• Based on simple ecological adjustment
  meatgrinder
• OVERALL RESULT FOR SCE lt 200 kWh per year. IN
  HOME AUDIT about 50 more savings than MAIL-IN.
• LONG VERSION ON-LINE Negligible savings, yet
  some evidence that install recommendations lead
  to savings.

AUDIT - RECOMMENDATION KWH/DAY
PATTERN IMPACT
STDERR KWH/YR T_VAL ---------------------
--------------------------------------------------
-- IH_AUDIT, ANY REC -0.8621
0.0546 -314.7 -15.79
IH_AUDIT,PRACTICE -0.8621 0.0546
-314.7 -15.79 IH_AUDIT, INSTALL
-0.8693 0.0561 -317.3 -15.50
MI_AUDIT, ANY REC -0.5802
0.0203 -211.8 -28.58
MI_AUDIT,PRACTICE -0.5805 0.0203
-211.9 -28.60 MI_AUDIT, INSTALL
-0.8110 0.0260 -296.0 -31.19
OL_AUDIT, ANY REC 0.1005 0.0360
36.7 2.79 OL_AUDIT,PRACTICE
0.1010 0.0360 36.9 2.81
OL_AUDIT, INSTALL -0.2850
0.0554 -104.0 -5.14
6
Remaining Issues and Recommendations

• Ecological trend consumption approach is an
  effective way to isolate adjusted gross savings
• Applicable to most consumption analyses of
  residential and small commercial programs
• Still need to track savings that flow causally
  through adoptions of HEES recommendations
• Need to understand measure-level impacts
• But we have extreme collinearity due to
• Too many measures. Huge numbers of
  recommendations were made to every 04-05
  participant.

7
More questions?

• John Peterson
• Athens Research
• petersjw_at_aol.com
• [phone]
• Carol Yin
• Yinsight
• cyin_at_yinsight.net
• [phone]

8
Ecological Consumption Adjustment Approach Path
Model of Role of Ecological Trend

• 1. Almost no direct impacts of weather upon
  customer consumption.
• 2. Virtually all of the weather impacts flow
  through the ecological consumption term.
• 3. The net neighborhood trend term is very
  strong, 0.8931.
• Since weather only accounts for about 21 of
  neighborhood trend, this means that a great deal
  of the neighborhood adjustment involves either
  non-weather variables or micro-climatic impacts
  that are not well captured by weather stations.
  This unique impact is .8865 .8931 or 0.792.