20201202Avista to Staff 3 Supplemental.pdf

AVISTA CORPORATION
RESPONSE TO REQUEST FOR INFORMATION

JURISDICTION: IDAHO DATE PREPARED: 12/2/2020
CASE NO: AVU-E-20-10 WITNESS: Clint Kalich
REQUESTER: Staff RESPONDER: John Lyons
TYPE: Production Request DEPARTMENT: Energy Resources
REQUEST NO.: Staff-003 Supplemental TELEPHONE: [phone]

REQUEST:

Please provide all changes that the Company has made to the peak and energy forecast, if any,
from the one used in the 2020 Integrated Resource Plan in AVU-E-19-01 to the one filed in
AVU-E-20-10, and explain why such changes were made.

RESPONSE:

The peak and energy forecasts used to make the filing in AVU-E-20-10 used the same regression
analysis for the development of the forecasts used in the 2020 Integrated Resource Plan in
AVU-E-19-01. The only changes were the use of the updated actual data that became available
between July 2019 when the old forecasts were finalized and August 2020, when the current
forecasts were finalized.

The Company usually submits the load forecast from the most recently acknowledged IRP, which
is the 2020 IRP submitted in AVU-E-19-01. However, since the submissions of that IRP was
delayed from August 2019 until February 28, 2020, that load forecast was not the most current
available. The Company decided to submit the current load price forecast in AVU-E-20-10 from
the 2021 IRP that will be filed on April 1, 2021.

SUPPLEMENTAL RESPONSE: (December 2, 2020)

The actual data that was changed between the two load forecasts is the meter data from July 2019
through early August 2020 that is used as inputs to the load forecast model. The actual metered
data replaces the forecasted load data in the model as it becomes available.

The difference between the two forecasts reflects the impact of the economic assumptions as the
result of the COVID-19 induced recession which is assumed to have a long run impact on future
loads compared to the last IRP.

RECEIVED
2020December 2,PM 1:21
IDAHO PUBLIC
UTILITIES COMMISSION