20150812AVU to Staff 50 Attachment B.pdf

Distribution Grid Modernization Program
An Avista system efficiencies team, in a 2009 study, evaluated the potential energy savings that
could be achieved through distribution system upgrades. The study analyzed the value of selective rebuilds with “right sized” conductor replacements to reduce system losses, improve
system reliability, and to meet future load growth demand. A second study was conducted in 2013 to assess the benefits of distribution feeder automation for increased efficiency, operability, and reduced generation savings. The Grid Modernization Program combines the
work from these system performance studies to provide Avista’s 340,000 electric customers with a refreshed and modernized system that is ready to withstand the changing demands of the twenty first century.
The research team evaluated several automation and efficiency approaches to improve both
rural and urban feeders on our 27,600 mile electric distribution system. The reliability, energy
losses, reductions in operations and maintenance costs (O&M) and capital investment from the individual efficiency opportunities under consideration were combined and analyzed on a per
feeder basis. This approach provided a means to rank troubled feeders that were ready for
modernizing and compare net resource costs to achieve the desired benefits. The Grid Modernization Program combines the following upgrade work and addresses performance
enhancements:
• Primary & Secondary Conductor Efficiency Losses;
• Distribution Transformer Losses;
• Conservation Voltage Reduction (CVR);
• Integrated Volt/Var Control (IVVC), and;
• Fault Detection Isolation and Restoration (FDIR) opportunities;
The Distribution Grid Modernization Program’s charter criterion has grown to include a more holistic approach to the way Avista addresses each project. This program integrates work
performed under various initiatives at Avista including the Wood Pole Management Program,
the Transformer Change-out Program (PCB Mitigation), the Vegetation Management Program
and AASHTO Clear Zone and Car Hit Pole Re-Alignments. The Program includes the
replacement of undersized and deteriorating conductors, replacement of failed and end-of-life
infrastructure materials including wood poles, cross arms, fuses and insulators. Inaccessible
pole alignment, right-of-away issues, undergrounding and clear zone compliance issues are addressed for each feeder section as well as regular maintenance work such as leaning poles,
guy anchors, unauthorized attachments and joint-use management. This systematic overview
enables Avista to cost-effectively deliver a modernized and robust electric distribution system that is more efficient, easier to maintain and more reliable for our customers.
Figure 5.2 illustrates the reliability advantages and reasons for the program. Prior to the 2009 feeder rebuild pilot program, outages were increasing at up to 13 outages per year. After the
project, outages declined significantly. In the past two years, only one outage was recorded.
The program is in its second year of regular funding and its intended purpose of capturing energy savings through reduced losses, increased reliability and decreased O&M costs is being
realized. The feeders addressed through this program to date are shown in Table 5.3. The total energy savings, from both re-conductor and transformer efficiencies for all of these feeders, is approximately 5,616 MWh annually.

Staff_PR 050 Attachment B Page 1 of 2
Table 5.3: Current Feeder Construction Energy Savings
Feeder Service Area
Year Annual Energy
9CE12F4 Spokane, WA (9th & Central) 2009 601
BEA12F1 Spokane, WA (Beacon) 2012 972
F&C12F2 Spokane, WA (Francis & Cedar) 2012 570
BEA12F5 Spokane, WA (Beacon) 2013 885
CDA121 Coeur d'Alene, ID 2013 438
OTH502 Othello, WA 2014 21
RAT231 Rathdrum, ID 2014 148
M23621 Moscow, ID 2015 562
WIL12F2 Wilbur, WA 2015 1,403
WAK12F2 Spokane, WA (Waikiki) 2016 175
RAT233 Rathdrum, ID 2019 471
SPI12F1 Northport, WA (Spirit) 2019 127

The additional benefits ascertained through the work performed through the Distribution Grid
Modernization Program are just now coming to fruition and will require a multi-year study to verify all of the planned benefits. Figure 5.2: Spokane’s 9th and Central Feeder (9CE12F4) Outage History

0
10
20
30
40
50
60
70
2004 2006 2008 2010 2012 2014
9CE12F4 – Pilot Project
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