Review of the New England

1
Review of the New England Mini-Pilot DHP
Evaluation

• Why we ignore this study

2
General Information

• Study Goals are to provide a estimation procedure
  for utilities who want to use DHP technologies as
  a efficiency measure
• Use billing analysis methods to develop
  generalized engineering savings estimate
• Applied hourly, monthly regression analysis as
  strategy to develop a deemed savings table for
  utility program
• Includes supplemental fuel impacts as they appear
  in the particular sample
• Study conducted by KEMA and includes 145 total
  installations
• 40 sites selected for metering
• Metering done on space heat and total use
• Sometime space heat limited to the DHP zone
• A total of 29 sites of metered data used and 124
  site used for the billing analysis

3
Reported Results

• Heating savings estimated at about 2500
  kWh/installation.
• 95-120 kWh/MBTU (rated heating capacity)
• Developed from temperature regression applied to
  TMY temperatures in individual climates
• Cooling saving estimated at about 300
  kWh/installation
• 3-8kWh/MBTU (nominal cooling capacity)
• Developed from temperature regressions applied to
  various base case cooling equipment with TMY
  temperatures

4
Primary Critiques

• Heating analysis based on a temperature
  regression.
• No effort to assess balance point
• Normalization would occur based only on usage at
  particular temperatures
• Not consistent with PRISM or any of the HDD
  regressions used in this region
• Savings normalized to MBTU of heating capacity
• No evidence or rationale presented for this
  selection
• Introduces uncertainty in assessing the overall
  savings

5
Conclusions

• Regression specification introduces substantial
  error
• Use of this method to generalize to annual
  climate without simulation or some sort of
  engineering calculation is uncertain
• The std. error or any other indicator of the
  quality of the model is absent
• R2 not reported except in aggregates and not very
  good at that
• This method and result unlikely to produce
  generalized savings results