Tools- of Changes

Ramp-Up, Dependability and Persistence of Savings from Home Energy Reports

This 2015 US study finds that energy reductions from Home Energy Reports are statistically significant within two weeks and relatively stable in the short run. 

• KEY RESULT 1: QUICK RAMP-UP: SAVINGS WITHIN TWO WEEKS
  
  After the first report is mailed out, savings appear to increase rapidly after one week, and are After the first report is mailed out, savings appear to increase rapidly after one week, and are statistically significant after two weeks.
  
  Implication: Once deployed, HER programs can be a fast-acting resource for reducing electricity consumption. This is especially true with respect to traditional energy efficiency programs such as whole house retrofits, which typically involve a lengthy process of several months between the time when customers get an energy audit, decide on a retrofit package, have a contractor install and commission measures, and observe energy savings on their utility bill.

• KEY RESULT 2: SAVINGS ARE RELIABLE?THEY PERSIST BETWEEN MAILINGS AND ARE RELATIVELY STABLE
  
  Savings persist between mailings: there are statistically significant savings every day between mailings. The savings are relatively stable: after the first mailing, there is no statistically significant growth or decline in savings over time, and no statistically significant variation in savings day-to-day.
  
  Implication: Savings from HERs appear to persist and provide a stable resource for load reduction in the short-term; this is useful information for system and program planning as well as load procurement and forecasting. Because the savings appear to stabilize, and do not significantly decline in the eight weeks between mailings 3 and 4, or 4 and 5, it may be possible to increase the duration between reports without affecting the level.