Transcript loadslides.ppt

Load Data for Vermont
Docket 7081 workshop
9/30/05
Vermont Load Facts
• Vermont is a dual peaking region (summer and winter
peak loads are approximately equal)
• Vermont has a “flatter” daily load profile and annual load
cycle than is typical in New England (with a relatively flat
profile from mid-morning into the evening)
• Vermont’s average load level is much higher than New
England’s
– For the period 9/1/04 to 8/31/05, Vermont’s average load was
67% of peak, while New England’s was 57% of peak
• Vermont has seen load growth in all seasons (spring,
summer, fall and winter) which has made maintenance
and construction difficult and costly
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Consequences . . .
•
Vermont has been much more successful than most regions at using the full capacity
of its system (for more hours than typical)
•
One chief consequence of this fact is that resources needed for system reliability
(transmission system elements, generation, alternatives, etc.) are needed over
extended portions of the day, and potentially for many consecutive days
•
This means when a problem arises at peak load levels, the exposure quickly
becomes large
•
If the system cannot reliably take out single system elements for maintenance at
intermediate load levels, then the ability to do maintenance is difficult at best (difficult
to schedule with neighboring utilities / ISO-NE and local generation, is weather
dependent, unplanned outages difficult are resolve and cancel planned work, limited
work crews result in prioritizing work)
•
Maintenance activities are being forced onto weekends, holidays, evening hours and
spread out over multiple days
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Vermont Load Data
(based on 9/1/04 to 8/31/05 data)
VT load level
1050
1000
950
900
850
800
750
700
# of hours
VT load level
1050
1000
950
900
850
800
750
700
# of days
23
120
496
1037
1906
3136
4616
5571
7
29
73
131
199
273
336
353
% of total hours
0.3%
1.4%
5.7%
11.8%
21.8%
35.8%
52.7%
63.6%
% of total days
1.9%
7.9%
20.0%
35.9%
54.5%
74.8%
92.1%
96.7%
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9/30/05 Docket 7081 Workshop D.LaForest
9/19/2005
9/12/2005
9/5/2005
8/29/2005
8/22/2005
8/15/2005
8/8/2005
8/1/2005
7/25/2005
7/18/2005
7/11/2005
7/4/2005
6/27/2005
6/20/2005
6/13/2005
6/6/2005
VT Load (MW)
VT SUMMER LOAD PROFILE - 2005
1100
1050
1000
950
900
850
800
750
700
650
600
time
5
9/30/05 Docket 7081 Workshop D.LaForest
3/18/2005
3/11/2005
3/4/2005
2/25/2005
2/18/2005
2/11/2005
2/4/2005
1/28/2005
1/21/2005
1/14/2005
1/7/2005
12/31/2004
12/24/2004
12/17/2004
12/10/2004
12/3/2004
11/26/2004
11/19/2004
11/12/2004
11/5/2004
10/29/2004
10/22/2004
10/15/2004
VT Load (MW)
VT WINTER LOAD PROFILE - 2004/05
1100
1050
1000
950
900
850
800
750
700
650
600
time
6
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