Transcript Industry Brainstorm on increasing Export Capacity

Industry Brainstorm on
increasing Export Capacity
From Alberta to B.C.
January, 2006
Who participated?
Company
ATCO Power
Participants
Carl Fuchshuber
Powerex
TransAlta
Gordon Dobson-Mack
Jim Paton
Ron Strem
TransCanada
Bill Hosie
Dan Levson
Larry Sibbald
AESO
Independent
Jeff Palermo (consultant)
Trent Coroy (consultant)
Purpose of Brainstorm
• Identify as many quality ideas as possible
that can increase Export capacity on B.C.
Alberta Tie Line
• Brainstorming temporarily suspends
critical processes
• Time frame for ideas: 6 months to 5 years
• Long lead times on some projects
– Need early identification and initiation
• E.g. A solution for 2011 may need initiation now
Purpose of Prioritization Process
• Develop consensus on prioritizing projects
based on their cost and benefits in increasing
export capacity
• Criteria used to prioritize projects:
– Time to implement
– How proven is the technology
– Approximate cost versus magnitude of export
capacity
– Issues that the technology addresses
• Projects prioritized into three groups
• Analysis based on Jan 06 industry knowledge of
transmission limitations
Summary of Results
• Three “urgent and important” projects
• Twelve more “important” Priority-1 projects
– Consider for approval and immediate
resourcing
• Three – Priority-2 Projects
– Need further study and evaluation
• Thirteen – Priority-3 Projects
– Park these ideas for review at a later date
Urgent Project 1
• Thermal capacity assessment and upgrades strategy for
limiting elements
– Thorough inventory of each element of transmission backbone
•
•
•
•
Transmission lines (ground clearance, conductor replacement)
Breakers
Current transformers
Busses, jumpers
– Identify lowest cost options to solve limits
– Identify database errors, if any, that could create artificial
constraints
– Start work immediately as thermal constraints rather than
dynamic constraints are currently limiting exports
Urgent Project 1b
• Create transmission limitations document
– Limiting operating criteria
– Limiting contingencies by facility
– Consequence of each contingency
– Action required to mitigate limitations
– Cross references to support studies
Urgent Project 2
• Expanded Remedial Action Schemes
– Develop a North South GRAS (underway?)
• Triggered by loss of ATC limiting double circuit or single
circuit line outages
– Develop a 500 kV BC Tie RAS to mitigate loss of ATC
limiting double or single circuit line outages
– Expand the use of undervoltage relays in a RAS to
prevent voltage collapse
– Develop Generator MW ramp down scheme to
automatically respond to thermal line overloads
(which have a longer response time)
Urgent Project 3
• Thermal Monitoring – Indirect Sensors
– Use indirect sensors such as weather stations
to monitor weather, sunlight, temperature and
wind
– Use these indications to create a real time
assessment of thermal limits on the system
– Proven technology
– Capacity should be higher during:
• Cooler days, night time, windier conditions
• Risks are higher during storm conditions
Other Priority-1 Projects
1. Tie tripping export shedding scheme
– Automatically ramp down exports when
voltages fall below predetermined levels
2. New 500 kV reactor breaker at Langdon
– Reactors can be switched out pre and post events to
support southern Alberta voltage
3. Encourage more north south capacity
increases
4. Explore BC side solutions
5. BCTC AESO coordination
Other Priority-1 Projects – cont.
6. Rebalancing north-south corridor lines
–
use phase shifters, new switching stations
7. Increase conductor capacity
–
Use new high capacity conductor technology on
critical lines
8. Over-frequency generation shedding scheme
(over 800 MW)
9. Saskatchewan Tie enhancements
–
Sask Tie can modulate voltages, RAS to increase exports to
Saskatchewan on a BC Tie trip, increase imports for southern
Alberta undervoltage concerns
Other Priority-1 Projects – cont.
10. Use weather adjusted criteria
– Use N-2 criteria only during adverse weather
conditions (when almost all contingencies occur),
otherwise use N-1 with safety nets
11. Use real time current measurements
– Replace proxies like MW, use actual current
12. Operate systems on Live database of system
conditions
– Use pre-calculated limits under various conditions
– Flows limited on pre-calculated contingencies, not
settings
Lower Priority Projects
• Three - Priority 2 Projects
– Need further study and evaluation
• Twelve – Priority 3 Projects
– Park these ideas for review at a later date
• Key caveat on prioritization
– If AESO sees more merit in any of these 16
projects, priority could be increased
Conclusion
• Process was worthwhile
• Will likely be the first of many over the next
5 years as north south capacity becomes
tighter
• Based on current knowledge of the cause
of limitations on the system
• Thanks to AESO for its support of this
brainstorming process