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April 20, 2007
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VIA OVERNIGHT DELIVERY
Idaho Public Utilities Commission
472 West Washington
Boise, ID 83702-5983
Attention:Jean D. Jewell
Commission Secretary
Re:Case No. PAC-6rz~o
In the Matter of the Petition of Rocky Mountain Power for an Order Revising
Certain Obligations to Enter into Contracts to Purchase Energy Generated by
Wind-Powered Small Power Generation Qualifying Facilities
PacifiCorp (d.a. Rocky Mountain Power) hereby submits for filing an original and eight copies
of its Petition of Rocky Mountain Power for an Order Revising Certain Obligations to Enter into
Contracts to Purchase Energy Generated by Wind-Powered Small Power Generation Qualifying
Facilities.
Service of pleadings, exhibits, orders and other documents relating to this proceeding should be
served on the following:
Brian Dickman
Manager, Idaho Regulatory Affairs
PacifiCorp
One Utah Center, Suite 2300
201 South Main
Salt Lake City, UT 84111
brian. dickman~pacificorp. com
It is respectfully requested that all formal correspondence and Staff requests regarding this
material be addressed to:
Bye-mail (preferred):datarequest~pac ifi corp. com
By regular mail:Data Request Response Center
PacifiCorp
825 NE Multnomah, Suite 2000
Portland, Oregon, 97232
By fax:(503) 813-6060
Sincerely,~K~(p.l\.
Jeffrey K. Larsen
Vice President, Regulation
Enclosures
cc: Service List
CERTDITCA TE OF SERVICE
I HEREBY CERTIFY that on this 20th day of April 2007, I served true and correct copy
of the foregoing PETITION upon the following named parties by the method indicated below,
and addressed to the following:
Jean Jewell
Idaho Public Utilities Commission
472 West Washington Street(83702)
O. Box 83720
Boise, ill 83702
Jean. iewell (g)puc.idaho.gov
Barton Kline
Monica Moen
Lisa Nordstrom
Idaho Power Company
PO Box 70
Boise, ill 83707
bkline
(g)
idahopower .com
mmoen (g)idahopower.com
lnordstrom
(g)
idahopower .com
Scott Woodbury
Deputy Attorney General
Idaho Public Utilities Commission
472 West Washington Street(83702)
O. Box 83720
Boise, ill 83702
Scott. woodbury (g)puc.idaho.gov
Richard L. Storro
Director, Power Supply
A vista Corporation
1411 E. Mission Avenue
O. Box 3727, MSC-
Spokane, W A 99220-3727
dick.storro (g) avistacorp.com
R. Blair Strong
Paine, Hamblen, Coffin, Brooke & Miller
717 West Sprague Avenue, Suite 1200
Spokane, W A 99201-3505
r. blair .strong (g) painehamblen.com
PETITION OF ROCKY MOUNTAIN POWER
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Peter J. Richardson
Richardson & O'Leary PLLC
515 N. 27th Street
PO Box 7218
Boise, ill 83702
peter (g)richardsonandoleary .com
William J. Batt
John R. Hammond, Jr.
Batt & Fisher, LLP
101 S. Capitol Blvd., Suite 500
PO Box 1308
Boise, ill 83701
wjb (g) battfisher .com
jrh (g) battfisher .com
Michael Heckler
Director of Marketing & Development
Windland Incorporated
7669 W. Riverside Dr., Suite 102
Boise, ill 83714
mheckler(g)windland.com
Dean Miller
McDevitt & Miller LLP
420 W. Bannock
Boise, ill 83702
j oe (g) mcdevitt-miller .com
Armand Eckert
Magic Wind LLC
716-B East 4900 North
Buhl, ill 83316
Glenn Ikemoto
Principal
Energy Vision LLC
672 Blair Ave.
Piedmont, CA 94611
glenni (g)pacbell.net
ANSWER OF ROCKY MOUNTAIN POWER
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David Hawk
Director, Energy Natural Resources
R. Simplot Company
999 Main St.
PO Box 27
Boise, ill 83707-0027
dhawk(g)simplot.com
R. Scott Pasley
Assistant General Counsel
R. Simplot Company
999 Main St.
PO Box 27
Boise, ill 83707-0027
spasley (g) simplot.com
William M. Eddie
Advocates for the West
1320 W. Franklin St.
PO Box 1612
Boise, ill 83701
billeddie
(g)
rmci.net
Troy Gagliano
917 SW Oak St., Suite 303
Portland, OR 97205
LeRoy Jarolimek
605 S. 600 W.
Burley, ill 83318
leroviarolimek
(g)
hotmail.com
Gerald Fleischman
11535 W. Hazledale Ct.
Boise, ill 83713
gfleisch986
(g)
hotmail.com
ANSWER OF ROCKY MOUNTAIN POWER
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~~~
Supervisor, Regulation Administration
Dean S. Brockbank
Sr. Counsel
Rocky Mountain Power
201 South Main, Suite 2300
Salt Lake City, Utah 84111
Telephone: 801-220-4568
Facsimile: 801-220-3299
Attorney for Rocky Mountain Power
BEFORE THE IDAHO PUBLIC UTILITIES COMMISSION
IN THE MATTER OF THE PETITION OF
ROCKY MOUNTAIN POWER FOR AN
ORDER REVISING CERTAIN
OBLIGATIONS TO ENTER INTO
CONTRACTS TO PURCHASE ENERGY
GENERA TED BY WIND-POWERED SMALL)
POWER GENERATION QUALIFYING FACILITIES
No. PAC-O 7 -
PETITION
Rocky Mountain Power, a division of PacifiCorp ("the Company ), pursuant to the Rule
31, IDAPA 31.01.01.031 hereby petitions the Idaho Public Utilities Commission
Commission ) to issue an Order:
Restoring the cap on entitlement to published avoided cost rates for wind-powered small
power generation facilities that are qualifying facilities (nQFs ) under Sections 201 and 210 of
the Public Utility Regulatory Policies Act of 1978 (npURPAn) from the current level of 100 kW
to 10 average MWs per month (n 10 aMWn), subject to the following conditions:
Reducing the published avoided cost rates applicable to purchases by
Rocky Mountain Power of electric power from wind-powered QFs by $5.04 per MWh,
which amount represents the inflation-adjusted integration costs of that wind power, to be
applied against published avoided cost rates except in those circumstances where the QF
PETITION OF ROCKY MOUNTAIN POWER - 1
developer agrees in the power purchase agreement with Rocky Mountain Power to
deliver QF output to Rocky Mountain Power on a firm hourly schedule;
Removing the requirement that the 90%/110% performance band be
applied to purchases from wind-powered QFs;
Authorizing Rocky Mountain Power to purchase state-of-the-art wind
forecasting services to provide Rocky Mountain Power with forecasted wind conditions
in those geographic areas in which wind generation resources are located, provided that
QFs will reimburse Rocky Mountain Power for their share of the on-going cost of the
wind forecasting service, in proportion to their percentage share of the wind.,generator
capability being supplied to Rocky Mountain Power from that area;
Requiring QFs to deliver a "mechanical availability guarantee" to Rocky
Mountain Power to demonstrate monthly, except for scheduled maintenance and events
of force majeure or uncontrollable force, that the QF was physically capable and
available to generate a full output during 85% of the hours in a month;
Clarifying the rules governing the entitlement to published rates to prevent
all QFs, whether wind or non-wind, capable of delivering more than 10 aMW per month
from structuring or restructuring into smaller projects for the purpose of qualifying for
the published avoided cost rates; and
Clarifying that the cap on entitlement to published avoided 'Cost rates shall
be restored to 10 aMW only until PacifiCorp s renewable targets for each calendar year
in the most recently acknowledged Integrated Resource Plan are met.
PETITION OF ROCKY MOUNTAIN POWER - 2
BACKGROUND
Idaho Power Company filed a Petition with the Commission on June 17, 2005, in Case
No. IPC-05-22 requesting that the Commission suspend its obligations under Sections 201 and
210 of PURPA to enter into new purchase and sales contracts for energy generated by wind-
powered QFs. On July 15, 2006, Rocky Mountain Power filed a Petition to Intervene, Brief on
Requested Temporary Suspension, and Direct Testimony in Case No. IPC-05-22 in which it
recommended that the Commission temporarily suspend Rocky Mountain Powers PURP A
purchase obligations in the same manner as requested by Idaho Power. In Order No. 29839,
issued on August 4, 2005, the Commission reduced the published rate eligibility cap for QF wind
projects from 10 aMW per month to 100 kW and required individual contract negotiations for
QFs larger than 100 kW for Rocky Mountain Power, Idaho Power and Avista.
Rocky Mountain Power has actively participated in Case No. IPC-OS-22 and in follow-
up wind workshops in Idaho. In addition, Rocky Mountain Power has continued to study and
analyze the impact of integrating wind generation into its multi;.;state electrical system, utilizing
its existing integrated resource planning process.
Recently, Idaho Power Company has filed Petitions respecting PURPA purchase
obligations in two different dockets, Case Nos. IPC-E-O7-03 and IPC-07-O4. Avista made a
similar filing in Case No. A VU-07-02. This Petition reflects recommendations made by Idaho
Power Company and A vista with respect to their respective service tenitories. Rocky Mountain
Power concurs with those recommendations, and therefore recommends that similar policies be
adopted with respect to Rocky Mountain Power s PURP A purchase obligations.
PETITION OF ROCKY MOUNTAIN POWER - 3
II.
INTEGRATION COSTS OF WIND POWER TO BE REFLECTED
IN AN ADJUSTMENT TO PUBLISHED AVOIDED COST RATES
With respect to the costs of integrating wind generation into existing utility systems, the
Commission found in Order No. 29839, Case No. IPC-05-22, that the supply characteristics of
wind generation and related integration costs could provide a basis for adjustment of the
published avoided cost rates, an adjustment that may be different for each utility. The Company
recommendation is that published avoided cost rates for purchases by Rocky Mountain Power be
reduced by $5.04 per MWh, which amount represents the integration costs of that wind power, to
be applied against scheduled avoided cost rates in those circumstances, except where the QF
developer agrees in the power purchase agreement with Rocky Mountain Power to deliver QF
output to Rocky Mountain Power on a firm hourly schedule. The $5.04 per MWh represents the
wind integration cost included in the company s latest acknowledged IRP (the 2004 IRP)
adjusted for inflation.
Rocky Mountain Power submits herein as Exhibit A to this Petition, an ex-cerpt from the
PacifiCorp - 2004 IRP Appendix J - Renewable Generation Assumptions" in which PacifiCorp
provides a description of the methodology used and the results derived from PacifiCorp
analysis of the wind integration cost issue as part of the 2004 IRPprocess. The 2004 IRP was
originally filed on January 21, 2005 (Case No. PAC-05-02) and is the Company s latest
acknowledged IRP. In an Acceptance of Filing dated August 26, 2005, the Commission
acknowledged the 2004 IRP. Therefore, Rocky Mountain Power recommends that the published
avoided cost rates applicable to purchases by Rocky Mountain Power of electric power from
wind-powered QFs be reduced by $5.04 per MWh to account for the cost to integrate wind.
PETITION OF ROCKY MOUNTAIN POWER - 4
Rocky Mountain Power recommends that the applicable reduction be applied to the
published avoided cost rates to determine a purchase and ~ale price that will be established for
the duration of the contract. Rocky Mountain Power recommends this approach in order to
assure that QFs that deliver less than 10 aMW have a predictable rate.
ID.
ELIMINATION OF THE 90%/110% PERFORMANCE BAND
Idaho Power Company and Avista recommend the elimination of the 90%/110%
performance band, subject to several conditions. Rocky Mountain Power recommends that the
same policies be applied to the purchase of wind power by Rocky Mountain Power from QFs.
Rocky Mountain Power believes that its proposed discount captures, as best as can be
determined presently, the cost of integrating wind generation into the Company s system and,
therefore to some degree, takes into account the inherent difficulty of accurately forecasting the
availability of wind. The establishment of the discount will in large measure acco~nt for the
variability of wind, and thereby diminishes the need for a performance band for wind.
Furthermore, Rocky Mountain Power believes there is benefit to a level of consistency in the
structure of PURP A QF tariffs among utilities.
In lieu of a performance band structure, the Company supports the concept of
establishing a mechanical availability guarantee by the QF. This guarantee would encourage
wind developers to ensure that the maintenance is performed on the wind turbines and that they
maintain the readiness of their equipment throughout the full duration of the long-term contract.
Rocky Mountain Power has successfully implemented a mechanical availability guarantee in
power purchase agreements with other wind-powered QFs and continues to support this method.
PETITION OF ROCKY MOUNTAIN POWER - 5
Rocky Mountain Power also supports the concept that QFs should participate in funding
wind forecasting services, as a condition of not being bound by the performance band. Wind
forecasting services are specific to any given wind farm and therefore may not be able to be
shared with other wind farms within the same geographic area. To the extent that Rocky
Mountain Power could use the same wind data, the Company would propose to share 'Such
expense on a pro rata basis with QFs that are selling their power to Rocky Mountain Power
under long-term contracts, so that the QFs would pay a portion of the wind forecasting expenses
proportional to their share of the wind-generator capability within the Rocky Mountain Power
wind portfolio from that geographic region.
IV.
ADOPTION OF A RULE PREVENTING MULTIPLE PROJECTS
OWNED BY THE SAME PERSON FROM RECEIVING THE PUBLISHED
VOIDED COST RATES, IF LOCATED IN THE SAME SITE
Idaho Power Company and A vista have recommended adoption of a rule nearly the same
as that adopted by the Oregon Public Utility Commission. Rocky Mountain Power recommends
that the approach recommended by Idaho Power and A vista be applied to RQckyMountain
Power s purchases as welL
Wind projects are uniquely able to reconfigure themselves into various legal ownerships
solely for economic reasons, without disturbing or affecting in any way the project site or
structural design. In some circumstances, other generating technologies may have ~imilar
capabilities. Such projects under common ownership that reconfigure themselves into multiple
projects of a smaller capacity should not qualify for published avoided costs in Idaho. Rather,
these projects should negotiate directly with the Company to determine the appropriate avoided
PETITION OF ROCKY MOUNTAIN POWER -
cost price to be paid for energy delivered to Rocky Mountain Power taking into account the
specific attributes of the project.
Additionally, while fundamental economic differences in the avoided costs and wind
integration costs exist for different utilities, a uniform approach among Idaho jurisdictional
utilities is particularly useful to avoid unneeded incentives favoring one utility over another
solely due to different QF rules that might apply to different utilities.
APPLICATION TO WIND GENERATION
UP TO COMPANY'S SYSTEM-WIDE IRP TARGETS
Rocky Mountain Power recommends that the cap on entitlement to published avoided
cost rates be restored to 10 aMW only until the Company s system-wide wind resource
purchases meets the total wind targets, by calendar year, from the latest acknowledged IRP or
until Rocky Mountain Power files for changes to its avoided cost schedules, or files a new wind
integration cost study based on additional industry experience.
VI.
COMMUNICATIONS
Communications respecting this matter should be addressed to:
Dean S. Brockbank
Sr. Counsel
Rocky Mountain Power
201 South Main, Suite 2300
Salt Lake City, Utah 84111
Telephone: 801-220-4568
Fax: 801-220-3299
E-mail: dean.brockbank(g)pacificorp.com
PETITION OF ROCKY MOUNTAIN POWER - 7
Brian Dickman
Manager, Idaho Regulatory Affairs
Rocky Mountain Power
201 South Main Street, Suite 2300
Salt Lake City, UT 84111
Telephone: (801) 220-4975
Fax: (801) 220-2798
E-mail: brian.dickman(g)pacificorp.com
vu.
MODIFIED PROCEDURE
Rocky Mountain Power has sent a copy of this Petition via email to all the parties that
participated in Case No. IPC-05-22. If no parties fIle comments on Rocky Mountain Power
proposal, or indicate substantial opposition to Rocky Mountain Power s Petition in written
comments, Rocky Mountain Power requests that the Commission consider this Petition in
accordance with Rule 201 et seq., allowing for disposition by Modified Procedure. IDAPA
31.01.01.201 et seq.Rocky Mountain Power is receptive to further proceedings, if the
Commission believes, based on comments received, that further proceedings would be
advantageous.
WHEREFORE, Rocky Mountain Power respectfully petitions the Commission to issue
an Order:
Restoring the cap on entitlement to published avoided cost rates for wind-powered small
power generation facilities that are qualifying facilities under Sections 201 and 210 of the Public
Utility Regulatory Policies Act of 1978 from the current level of 100 kW to 10 average MWs per
month, subject to the following conditions:
Reducing the published avoided cost rates applicable to purchases by
Rocky Mountain Power of electric power from wind-powered QFs by $5.04 per MWh,
which amount represents the integration costs of that wind power, to be applied against
scheduled avoided cost rates in those circumstances, except where the QF developer
agrees in the power purchase agreement with Rocky Mountain Power to deliver QF
output to Rocky Mountain Power on a firm hourly schedule;
PETITION OF ROCKY MOUNTAIN POWER - ~
Removing the requirement that the 90%/110% performance band
requirement be applied to purchases from wind-powered QFs;
Authorizing Rocky Mountain Power to purchase state-of-the-art wind
forecasting services to provide Rocky Mountain Power with forecasted wind conditions
in those geographic areas in which wind generation resources are located, provided that
QFs will reimburse Rocky Mountain Power for their share of the on-going cost of the
wind forecasting service, in proportion to their percentage share of the wind-generator
capability being supplied to Rocky Mountain Power from that area;
Requiring QFs to deliver a "mechanical availability guarantee" to Rocky
Mountain Power to demonstrate monthly, except for scheduled maintenance and events
of force majeure or uncontrollable force, that the QF was physically capable and
available to generate at full output during 85% of the hours in a month;
Clarifying the rules governing the entitlement to published rates to prevent
all QFs, whether wind or non-wind, capable of delivering more than 10 aMW per month
from structuring or restructuring into smaller projects for the purpose of qualifying for
the published avoided cost rates; and
Clarifying that the cap on entitlement to published avoided cost rates shall
be restored to 10 aMW only until PacifiCorp s total wind portfolio meets the Company
annual renewable targets in the action plan in the company s latest acknowledged IRP
RESPECTFULL Y SUBMITTED this 20th day of April, 2007.
Rocky Mountain Power
By:j;)PR
~~
. f\
Dean Brockbank, Sr. Cou sel
Rocky Mountain Power
PETITION OF ROCKY MOUNTAIN POWER - 9
EXHIBIT A
AN EXCERPT TAKEN FROM
ACIFICORP - 2004 IRP
APPENDIX J
RENEWABLE GENERATION
ASSUMPTIONS
EXHmIT A
AN EXCERPT TAKEN FROM "PACIFICORP - 2004 IRP APPENDIX J -
RENEW ABLE GENERATION ASSUMPTIONS"
Wind Integration Costs
PacifiCorp developed a methodology for calculating the added cost of integrating wind resources
into the system during the 2003 IRP. This section will provide a brief review of the methodology
and update of the original assumptions.
Utilities maintain reliability by dynamically responding to imbalances in demand and supply.
Resources are scheduled to ramp in generation when loads are increasing, and to reduce
generation as loads subside for the day~ther resources are made available to respond on a near
instantaneous basis. Flexible resources that can change their output over periods of hours and
seconds are key to responding to the rapid changes in loads and unexpected changes in resource
output (outages and derates). It is expected that additions of wind resources will increase the
need for flexible resources to meet reliability standards.
The amount of unloaded, relatively flexible resources available on any hour is called the
operating reserve-resources available on short notice to provide additional power as needed.
Calculating the quantity of reserves required to maintain system reliability has not been an exact
science as practiced in the utility industry. Many years of experience with thermal and hydro
resources has lead to some industry standards. One such standard is to maintain contingency
reserves30 equal to the sum of 5% of load served by hydro resources and 7% of lQad served by
non-hydro resources operating to meet load on any hour. In general, utilities are required to have
sufficient operating reserve to meet the North American Electric Reliability Council (NERC)
performance standards.
In addition to needing to assure sufficient flexible resources available to meet demand
obligations, PacifiCorp needs to understand the extent to which the system incurs additional
operating costs associated with the relatively volatile and less-predictable nature of wind
generation. Those costs are termed Imbalance Costs for the purpose of this paper.
Because of the implications for reliability and PacifiCorp s role as control area service provider,
PacifiCorp undertook to define methods of assessing both incremental reserve requirements, and
additional dispatch costs due to integrating wind resources on its system. While it is clear that the
methods employed will require future refinements, PacifiCorp feels that they represent a
30 Contingency Reserve is a category of Operating Reserve that must be made available to quickly respond when
some portion of the power system experiences a failure such as transmission line outages, generator failures, etc.
31 Note that the term Imbalance Cost as used in this paper is not directly related to the defmition of imbalance
charges found in FERC pro-forma transmission tariffs. As used in this paper, imbalance costs refer strictly to the
additional operating expenses incurred as a result of adding wind generation to the system. Such costs may include
the costs of additional market sales and purchases, more frequent unit startups, and the cost of dispatching reserve
units.
PETITION OF ROCKY MOUNTAIN POWER- 10
reasonable approximation for estimating wind integration costs given the characteristics of
PacifiCorp s control areas until further analysis can be undertaken.
Imbalance Costs
For the 20031RP, Henwood's MARKETSYM model was used to estimate the difference in
system costs32 between firm contract delivery at constant rates over time, and an equivalent
amount of energy from simulated wind resources. Wind -generation fluctuated hourly based on
available historical wind data.33 The alternatives were tested for wind and contracts separately
on the west and east sides of PacifiCorp' s system. The model was run for three future years at
five levels of added wind capacity and averaged to estimate imbalance costs.
The model showed relatively little difference between the east and west sides of the PacifiCorp
system. At wind penetration levels of 1,000 MW MARKETSYM reports average imbalance
costs of about $3/MWh in year 2002 dollars.
Incremental Operating Reserve Requirements
Incremental reserve requirements were estimated by comparing the relative dynamic range of
loads with and without wind. The standard deviation of hourly loads for a year was calculated.
A new standard deviation was computed after subtracting out various levels of wind generation.
The fractional difference in standard deviations was taken as an estimate of the increased need
for operating reserves.
Assuming that the fractional increase in standard deviation of hourly loads with and without
wind is proportional to the increased need for reserves, the incremental need for reserves can be
estimated. Factoring in the cost of reserve results is an estimation of the cost of incremental
operating reserves attributable to wind.
Operating reserves are typically held on hydro units when available, and higher variable cost
thermal units to the extent they are needed. PacifiCorp holds an existing portfolio of resources
that can be arranged from highest variable cost to lowest. Holding reserves on unloaded flexible
hydro units, and above-market-cost thermal units incurs relatively little cost. For these reasons,
some wind site locations supported by flexible generation within the system may be preferable
over other locations. However, as the need for reserves increases, the likelihood of having to
carry reserves on economic thermal units and loaded hydro units increases. This means that the
cost of holding reserves increases with the level of reserves being held. Costs of holding reserve
may increase or decrease over time due to changes in overall market prices.
Caveats
The foregoing analysis is thought to represent a reasonable approach to estimating costs
associated with integrating wind resources into PacifiCorp s power system until further analysis
32 System costs = dispatch costs + market purchase costs - market sales revenues
33 The hourly wind sites modeled in this study were based on simulated historical hourly generation data from a
wind resource on PacifiCorp s west system and Foote Creek on the east system. The two data streams were
modified by lagging by one hour and moving data ahead one hour to create four new data ranges for the model. The
two west side streams were added together and then sized to the installed capacity level for the West side site. The
two new Foote Creek sites were combined and prorated up to the various installed capacity levels for the East side
site. A single year of hourly generation was repeated for each of the three years of the study.
34 The cost
of reserves also changes over hours and season. This (:alculation assumes an average cost over the year.
PETITION OF ROCKY MOUNTAIN POWER - 11
can be performed. Many assumptions have necessarily been made to do this analysis. Some of
the main assumptions include:
. MARKETSYM's ability to accurately reflect imbalance costs
. Operating reserve requirements are proportional to hourly load volatility net wind generation
. Sufficient transmission to fully integrate wind resources with the system
. Intra-hour variability is not significant
Updates to Wind Integration Costs
At a penetration level of 1,000 MW, the cost of incremental operating reserves in the 2003 IRP
for a wind site with a capacity factor of 30% was $2.72/MWh. Combined with the $3.00 /MWh
estimate for imbalance, the total integration cost for 1 000 MW was approximately $5.50/MWh.
Since this analysis was first completed, the assumption for imbalance costs have remained
unchanged at $3.00 MWh in 2002 dollars but the cost of incremental reserves has been updated
for new market prices. The same methodology was used in the update, only the cost of reserves
was adjusted. Currently for 1,000 MW of wind capacity split equally in the system, the 20 year
levelized cost of integration in 2004 dollars is estimated to be $4.64 MWh.
PETITION OF ROCKY MOUNTAIN POWER - 12