WSP02492

• File Number: 8220.100.50
• Description: CRSP
• Basin: Colorado Mainstem
• Date: 3/1/1988
• Author: WAPA
• Title: Replacement Resources Processes - Final Methods Report - Executive Summary
• Water Supply Pro - Doc Type: Publication

resource acquisition process, but in other
resource planning functions as well. '

Selection of Modeling Tools

It was necessary initially to identify
the modeling tools to be used and to select
appropriate models to develop or modify
for the proof-of-concept analysis. As a
first step, a research and literature review
of software tools, methodologies, and
modeling approaches was undertaken,

Several modeling approaches were
considered for evaluating replacement
power alternatives. These ranged from
production cost models, to capacity
expansion models based on linear or
dynamic programming. Use of a spread-
sheet to calculate levelized-costs was also
considered as a simplified modeling
approach. The preferred modeling
approach identified for the replacement
resources acquisition process is use of a
spreadsheet model for resource screening
and a production cost model for integrated
analysis,

The diversity of pricing structures
and other replacement resource charac-
teristics will make it difficult to determine
the lowest cost alternative through simple
review. On the other hand, preparing a
detailed and time-consuming integrated
analysis for all responses received would
be too time-consuming.

,
To limit the number of alternatives
evaluated in detail, a screening analysis
was developed that provides a straightfor-
ward method to process the basic data,
represent each alternative on a consistent
basis, and create an economic ranking of
the alternatives based on the estimated
levelized per-unit cost at different capac-
ity factors. Based on the results of the
screening analysis, Western can select the
alternatives to be evaluated in detail using

a fair and objective process,

The production cost model,
MULTISYM, was selected for performing
the detailed integrated analysis of replace-
ment power alternatives primarily because
it offered the key features required for
modeling such an extensive geographic
area with multiple interacting systems.
The program is developed, marketed
commercially, and supported by a third
party, Henwood Energy Services, Inc.

The Colorado River Simulation
System model was used to represent the
Colorado River System and determine the
monthly hydro-electric generation for the
Reclamation's hydroelectric generation
projects in MULTISYM. The principal
data source used to construct the
MULTISYM model of all the other
electric utilities, loads and resources in
Western's marketing area was Resource
Data International, Inc. This company was
selected primarily because it is both
comprehensive and readily available to
Western.

Model Implementation

A potential course of action could
have been to implement the models using
system data already existing from other
studies, supplemented with "example" or
"representative" data. The course of
action used for the proof-of-concept
analysis was actually a more comprehen-
sive approach to model implementation,
which involved identifying data sources,
gathering most of the available data from
these sources, processing the data, and
then constructing a more comprehensive
model. Using comprehensive, rather than
representative, data in the current model
will provide benefits as a future time-saver
when Western begins to implement chosen
methods and potentially acquire replace-
ment resources,

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