Integrating Southwest Power Pool Wind to Southeast Electricity ...

It should be noted that, for Scenario 1, there are about 350 hours for which the UPLAN model
finds there is not enough available regulating capacity to ensure regulation requirements are met.
The shortage does not occur because insufficient regulating capacity exists, but rather because
the UPLAN solution prioritizes some regulating units for providing energy under the tight
system conditions where SPP is carrying all within-hour reserves. While in reality, the system
would be able to operate out of this relatively easily by bringing additional “non-regulating”
units online to free up regulating capacity, the model places more of a premium on meeting
energy requirements at low cost and therefore does not meet regulation requirements for these
hours in Scenario #1 and a smaller number of hours in Scenario #2. This is summarized in Table
5-9. For Scenarios 3 and 4 this does not happen. As can be seen, this is relatively small in
comparison to system size, however it does indicate that SPP would have to operate its system
very tightly if it had to meet regulation requirements to balance wind by itself. For some hours of
the year, the operators may find themselves needing to move units out of merit to provide
regulation.
Table 5-9: Regulation requirement violations for SPP
# Violations Avg (MW) MWh Max (MW)
Scenario 1 352 285 100548 984
Scenario 2 41 193 7942 541
Increase in SC 1 311 92 92606 443
Scen. #3 vs. Scen. #2 – Benefits of Sharing Scheduling and Reserve
Requirements
Relative to Scenario #2, Scenario #3 is modeled such that SPP, TVA, SBA, and Entergy share
resources for scheduling day-ahead and share contingency and with-in-hour reserve requirements
for the wind. As noted in chapter 3, this allows for a significant reduction in total reserve carried
due to load and wind diversity and reduced contingency requirements. Regulation decreases 200
MW and spin reduces 1900 MW due to the contingency reserve reduction. This reduction in
reserve and sharing of resources in the day-ahead commitment leads to the larger differences in
production cost results described previously.
Table 5-10: Difference** in Generation for Scenario 3 vs. Scenario 2
Change in
SERC SERC
GW EES TVA SBA SPP West East Total
CC 0.03 (1.00) (1.41) (0.03) 0.00 0.05 (2.37)
GT 0.00 (0.26) (0.03) (0.02) 0.09 0.07 (0.15)
Hydro - - - - - - -
Nuclear 0.00 - - 0.00 - (0.00) 0.00
Coal 0.03 0.50 0.47 0.62 0.50 0.32 2.45
Gasoil (0.06) - (0.00) (0.00) - 0.00 (0.06)
Wind - - - - - - -
Other 0.01 0.01 0.05 0.02 (0.01) 0.04 0.12
Total 0.01 (0.75) (0.93) 0.60 0.58 0.48 (0.00)
**Positive value represents increase in generation in Scenario #3 relative to Scenario #2.
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