Reliability and Resiliency - TVA Content... · 53 TVA Transmission at a Glance 16,000+ circuit...
Transcript of Reliability and Resiliency - TVA Content... · 53 TVA Transmission at a Glance 16,000+ circuit...
Reliability and Resiliency
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What is Reliability?
Electricity delivered in the right amounts precisely when and where it is needed
– Three Components:• Power Supply• Transmission• Regional Coordination
Maintain area reliability, meet regulatory requirements, and support regional growth
TVA measures Reliability by:
– Load Not Served (LNS)
– Connection Point Interruptions (CPI)
We say we are reliable, but what does that really mean?
System reliability is maintained through continual work to repair/ replace/ upgrade
system elements
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KY
SC
AL
AR NC
GA
IL WV
TN
VAMO
MS
69 kV and below Lines
115, 138, 161 kV Lines
230, 345, 500 kV Lines
Hydro Plant
Combustion Turbine
Fossil Plant
Nuclear Plant
TVA Power Service Area
State BoundaryTVA Geographic Information & Engineering
TVA’s Integrated System
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TVA Transmission at a Glance
16,000+ circuit miles of line operated at 115-kV to 500-kV
500+ substations and switchyards (100-kV and above)
103,000+ transmission structures on 237,000 right-of-way acres
1,200+ customer connection points
2 fully-operational Control Centers
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TVA Generation Assets
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System Operations Center: Nerve center of TVA
24 x 7 operations
Real-Time monitoring of the TVA Transmission System
System Operations Center fully backed up by the Regional Operations Center
Critical systems can be executed independently
Continuous balancing of load and generation
System Operations: Keeping the Lights On
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TVA Reliability: Duration of Outages
For 14 years, the TVA system has been 99.999%
reliable
TVA’s current performance is within first quartile industry performance
99.999% reliability = 7.8 system minutes of Load Not Served (LNS)
Issues putting 99.999% at risk:
– Aging Assets
– Tightening Regulations
– Changing System Conditions
9.45
7.89
6.00
4.884.21
6.19
3.344.04
3.61 3.72
5.84
4.654.14 4.07 4.03
0.00
1.00
2.00
3.00
4.00
5.00
6.00
7.00
8.00
9.00
10.00
1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013
TVA’s Historical LNS
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TVA Reliability: Frequency of Outages
TVA’s current performance is within first quartile industry performance for Connection Point Interruption Frequency (CPIf)
Includes sustained and momentary interruptions
Top impacts to frequency of customer interruptions:
– Weather (Lightning and Wind)– Aging Assets– Foreign Objects (Birds, Animals, and Debris)
1.41 1.40
1.171.03
0.90 0.880.79 0.74 0.81 0.81 0.75
0.67 0.71 0.70 0.77
0
0.4
0.8
1.2
1.6
1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013
Inte
rrup
tions
per
Con
nect
ion
Poin
t TVA’s Historical CPIf
Since 2004*, TVA has been a Top Quartile performer or better
*2004 was the first year of an Industry Benchmarking being available with all voltage
classes
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TVA Reliability: Consistency of Voltage
110000
120000
130000
140000
150000
160000
0 0.05 0.10 0.15
Tranmission Voltage Sag
Electrotek/EPRI PQView®
Vol
tage
(V
)
Time (s)
Vab
Voltage sags can shut down sensitive production systems
– Downtime costs for 50MW sensitive industry >$100k in production losses
TVA’s PQ Program goal is reducing voltage sags associated with transmission system faults
Program targeted at top 100 largest industries in the Valley:
Food Production Textiles Paper Printing Chemicals Rubber
Power Quality program is focused on keeping the industry in the TN
Valley running smoothly
Plastics Glass Primary Metals Electronics Transportation
Reliability and Resiliency
Transmission Voltage Sag
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TVA Reliability: Matching Generation to Load
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Transmission: Connecting Generation to Load
Real-Time balancing of generation (supply) and load (demand)
– Generation includes native sources and purchases
– Diverse plant types ramp at different rates
– Changing generation mix can significantly impact ability to meet load requirements
Sufficient Reserves must be maintained at all times to recover from unexpected large generation losses
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Planning for System Resiliency
Generation decisions cannot be made without Transmission support
– Projects must be in place to ensure power can still be delivered where needed
Robust Transmission system is needed to provide flexibility and respond to system events
– Localized storm damage does not impact the entire system
– Single generator loss can be balanced with power from another source
KY
SC
AL
AR NC
GA
IL WV
TN
VAMO
MS
69 kV and below Lines
115, 138, 161 kV Lines
230, 345, 500 kV Lines
Hydro Plant
Combustion Turbine
Fossil Plant
Nuclear Plant
TVA Power Service Area
State BoundaryTVA Geographic Information & Engineering
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Big Picture Reliability: Eastern Interconnection
TVA is one of 23 Planning Authorities in the Eastern Interconnection
TVA has 68 interconnections with 12 neighboring systems
Partner with other industry participants to,
– Prevent cascade of instabilities across neighboring systems (NE Blackout)
– Plan robust and flexible systems
– Guarantee resource adequacy
TVA partners with others to ensure the reliability of the Eastern Interconnection
and the U.S.
Reliability and Resiliency