Environmental Engineering Reference
In-Depth Information
between 2:00 and 4:00 a.m. In response, coal was ramped up from approxi-
mately 1,500 to 1,900 MW in 60 minutes beginning at 3:00 a.m.
Generation from all PSCO coal plants on September 28-29, 2008, contrasts
to generation a few days earlier (September 22-23). Figure 2.15 details the
hourly generation for both sets of days. Wind generation availability on
September 28-29 resulted in a significant reduction in coal-fired generation.
As was done for the July 2 case study, the emission rates associated with gen-
eration from September 22-23 were applied to the September 28-29 event.
Figure 2.16 shows the plants that were cycled to accommodate wind on
September 28-29. The Pawnee, Comanche, and Cherokee coal units were
cycled to balance the load. Figure 2.17 shows the coal generation avoided
during the wind event, aggregated to include all coal-fired plants. The event
2,500
Sept 22-23
2,000
Sept 28-29
1,500
1,000
500
-
3:00 pm
9:00 pm
3:00 am
9:00 am
3:00 pm
FIGURE 2.15
Comparison of PSCO coal plant generation on September 28-29 and September 22-23, 2008.
150
Cherokee
Pawnee
Hayden
Cameo
Comanche
Arapahoe
Valmont
Craig
100
50
0
-50
-100
12-1 am 1-2 am 2-3 am 3-4 am 4-5 am 5-6 am 6-7 am 7-8 am
-150
FIGURE 2.16
Hourly generation changes on September 28-29, 2008.
