WSP05225

• File Number: 8220.100.50
• Description: CRSP - Power Marketing
• Basin: Colorado Mainstem
• Date: 9/1/1983
• Author: USDOE/WAPA
• Title: Power Resources Study for Post 1989 Power Marketing Criteria
• Water Supply Pro - Doc Type: Publication

STUDY RESULTS

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Monthly generation (GWh) and available monthly capacity (MW) for each CRSP
plant plus a participating project plant at Fontenel1e was summed and
tabulated as total CRSP resources. These monthly tabulations (75 for GWh and
75 for MW), each 27 years in length, representing future conditions between
1983 and 2009 form the basis for the probability analysis. Headquarters
staff (A6300) in Golden, Colorado, performed all probability studies and
produced the computer graphics. Three periodS were selected for analysis.
Each began in 1990, one for a 10-year period, one for a 15-year period, and
one for a 20-year period. The 10-year period was chosen for further analysis
and eventually applied to the Post 1989 Marketing Criteria. This document
reports only those study results pertaining to the 10-year study period.
However, results of the lS-year and 20-year periods are on file and available
for inspection at Western's Salt Lake City Office.

Appendix A-l contains a summary of selected probabilities and associated
capacity values by months. Lowest capacity values for each season occurs in
the months of March and April. Critical load periodS occur in December or
January for the winter season and July or August for the summer season.
Therefore, critical seasonal capacity values and their associated
probabilities were selected from the lesser of December and January for the
winter season and the lesser of July and August for the summer season. Firm
capacity values were selected from the 90% probability level and adverse
values were used as the amount of capaCity not subject to surcharge in the
Post 1989 Power Marketing Criteria.

Appendix A-2 contains a summary of selected probabilities and associated
energy values by months. In addition, winter and summer season totals are
tabulated. It should be noted that the season totals are not the same as the
sum of the months in each season for each probability level. This is because
the seasonal sums were determined before the ranking process rather than
summing the individual months after ranking. Additionally, the arithmetic
mean is tabulated since it can and often does differ significantly from the
median or 50% probability level. The mean seasonal values were selected for
application in the Post 1989 Power Marketing Criteria.

Appendix A-3 is the probability plot of monthly capacity ranking all months
together. Appendices A-4 through A-15 are the probability plots of the
monthly capacity, ranking the individual months separately. Appendix A-16 is
the probability plot of monthly energy in the same manner as A-3. appendices
A-17 through A-28 are the probability plots of monthly energy in the same
manner as A-4 through A-15. Appendix A-29 is the probability plot of winter
and summer energy, ranking the individual seasons separately.

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