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Alberta
System - Labour Day
Weekend Operations
During
the long weekend in September, it appears an imbalance between
supply and demand caused spot gas prices to fall dramatically
in the Alberta market place. In order to understand these
unexpected changes, it is valuable to take a closer look at
the sequence of events that occurred leading up to this period:
|
Date
|
Event
|
| Friday,
Aug 31 |
Alberta
system linepack at 385 e6m3 and steady (target = 389 e6m3) |
| Saturday,
Sep 1 |
Field
receipts increase by approximately 8 e6m3/d from Aug 31
to Sep 1 (12 e6m3 from Aug 30 to Sep 1) |
| Saturday,
Sep 1 |
At
08:00, Alberta system linepack is 391 e6m3/d and packing
by ~6 e6m3/d |
| Saturday,
Sep 1 |
Export
nominations decrease by approximately 14 e6m3/d (273 e6m3/d
to 259 e6m3/d) |
| Sunday,
Sep 2 |
At
08:00, Alberta system linepack is 406 e6m3/d and packing
by ~12 e6m3/d. Overpressure conditions present in Northwestern
Alberta |
| Sunday,
Sep 2 |
Effective
08:00, supply/demand tolerances changed to 0/-20 %/TJs
from normal +10/-10 %/TJs levels |
| Monday,
Sep 3 |
At
08:00, Alberta system linepack is 411 e6m3/d and packing
by ~6 e6m3/d. Overpressure conditions continue in Northwestern
Alberta |
| Monday,
Sep 3 |
Effective
16:00, interruptible service restriction implemented upstream
James River to address facility integrity (overpressure)
concerns |
| Tuesday,
Sep 4 |
At
08:00, Alberta system linepack is 404 e6m3/d and drafting.
Tolerance change and IT restriction remain unchanged until
system conditions return to acceptable operating limits |
| Wednesday,
Sep 5 |
At
08:00, Alberta system linepack is 392 e6m3/d and steady.
System conditions returned to within acceptable operating
limits |
| Wednesday,
Sep 5 |
Effective
08:00, supply/demand tolerances returned to normal +10/-10
%/TJs levels |
| Wednesday,
Sep 5 |
Effective
16:00, IT restriction lifted upstream of James River |
Effective
September 1, 2001, TransCanada's Alberta System total export
nomination decreased by approximately 14 e6m3/d (500 mmcf/d).
As a result, net system supply exceeded net system market
demand and the Alberta System linepack began to significantly
increase. Nova Gas Transmission Ltd. (NGTL) was able to accommodate
all customers markets, however, net supply continued to exceed
net market as customers appeared unable to find replacement
markets fast enough. The imbalance in supply to market created
operational problems on the Alberta System and it became necessary
for NGTL to implement a 0/-20 tolerance change followed by
an interruptible receipt restriction on a portion of the Alberta
System.
NGTL
took the necessary steps to re-establish normal operating
conditions. There was generally good cooperation from all
sectors of the industry everyone's diligence and patience
in working through this period was appreciated by all.
For any
additional information on this event, please contact Rob
Swart at (403) 920-5590.
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