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August 27, 2013 Regional Planning Group Meeting. Houston Region Import Capacity Project. Background. Tie line capability limited to approximately 6500 MW currently Generation Previously or currently mothballed units: 1367 MW Additional units approaching 50 years old: 1174 MW
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August 27, 2013 Regional Planning Group Meeting Houston Region Import Capacity Project
Background • Tie line capability limited to approximately 6500 MW currently • Generation • Previously or currently mothballed units: 1367 MW • Additional units approaching 50 years old: 1174 MW • Recent generation additions have been relatively small • Houston is a non-attainment zone • Proposed Pondera (1300 -1380MW) has not provided Notice to Proceed since signing SGIA in 2010 • Recent ERCOT publications (2012 Constraints and Needs report and 2012 Long Term Study) show need for additional import path into Houston • CNP has serious concerns about reliability/resource adequacy for the Houston load pocket because of limited import capability 1
Older Units Possible future retirements - a total of 1939 MW in-service units will be older than 50 years by 2018. These resources were modeled as online in the Study Case. 2
Houston Load Pocket Projected Reserves Note: Resources include both generation and import capacity into Houston 3
Study Approach Phase I: Study Case Analysis • Modify SSWG 2015-2018 base cases created in February 2013 • Remove Pondera (1300 MW) • Add Deer Park Energy Center expansion (215 MW) • Add Calpine Energy Center expansion (200 MW) • CNP load matches 2012 ALDR (other than new transmission customers) • Non-coincident peak • Hot summer load level (102 degree F) • 2013 ALDR CNP load about 600 MW higher in 2018 than in 2012 ALDR • CNP studying over 1000 MW of industrial load not included in 2013 ALDR which could be on-line as early as 2016 4
Study Approach Phase I: Study Case Analysis • Use ERCOT Criteria: Planning Guide 4.1.1.2 (1)(b) • Take largest unit inside Houston “zone” out of service: Cedar Bayou Unit 2 (745 MW) • Perform Single and Common Mode contingencies (Common tower outage) • Overload of Singleton – Zenith circuits beginning in 2018 (100.8% in 2018) 5
Houston Region Phase I: Study Case Analysis Cedar Bayou 2 out-of-service 6
Phase I: Reliability Analysis – CB2 out • Sensitivity Analysis • Without 1367 MW mothballed generation – loading of 114% for year 2015 • New 500 MW generator inside CNP – loading of 92% for year 2018 7
Study Approach • Phase II: Interconnection Options and Initial Screening • Evaluate transfer capability of the 2018 Study Case and 25 Options • Use ERCOT 2012 average transmission costs to estimate each option • Include estimated costs of reinforcements • Rank Options based on Transfer Improvement Value (MW transfer increase) / (Cost) • Select best Options for additional analysis • Phase III: Interconnection Options Detailed Analysis • Evaluate voltage stability impacts and estimate reactive compensation for each Option • AC Contingency and Short-circuit analysis • Prepare detailed cost estimates using typical CenterPoint Energy costs • Identify preferred interconnection options that maximize increased transfer capability versus total project cost 8
Twenty-five Options Studied Options 1 - 16 Jordan 9
Twenty-five Options Studied Options 17 – 25 10
Phase III: Additional Studies Detailed Cost Analysis 13
System Configuration – Option 15 Option 15: Twin Oak – Zenith 345 kV 15
System Configuration - Option 24 Option 24: Zenith – Ragan Creek 345 kV 16
System Configuration - Option 25 Option 25: Limestone - Ragan Creek – Zenith 345 kV 17
Conclusions • Unless additional net generation or new import transmission paths into Houston region are constructed CNP will not comply with ERCOT’s Planning Criteria by year 2018. • 25 interconnection options studied. Three options are recommended based on technical and economical analysis. 18
Conclusions • Option 15: New Twin Oak - Zenith 345 kVdouble circuit: 2700 MW transfer capability improvement. $462 million project cost. 5.85 MW/$MM transfer/cost value. New line connects Oncor’sand CNP’s substations. Includes approximately $7.5 million in LCRA 138 kV line upgrades. • Option 24: New Ragan Creek – Zenith 345 kV double circuit: 1960 MW transfer capability improvement. $297 million project cost. 6.60 MW/$MM transfer/cost value. New line connects CNP’s Zenith substation to a new 345 kV Ragan Creek substation. Includes $5 million upgrade of TMPA Twin Oak - Jack Creek -Ragan Creek double circuit. Includes approximately $2 million in LCRA 138 kV line upgrades. • Option 25: New Limestone – Ragan Creek - Zenith 345 kV double circuit:2530 MW transfer capability improvement. $532 million project cost. 4.76 MW/$MM transfer/cost value. New line connects Limestone to new 345 kV Ragan Creek substation to Zenith substation. Includes approximately $5.5 million of LCRA 138 kV line upgrades. 19