FINAL FACILITY STUDY 230/69/13.8 kv Transformer Addition(s) at Badwater Substation 2009 T1 September 10, 2010
I. Introduction This is a revised facility study performed for Transmission Queue Request 2009 T1, Western Area Power Administration (Western). In June of 2010, the Customer and the Customer s Member expanded the facility and system impact study scope for the Badwater Substation to include three transformation and bus operation configurations: 1. The addition of KV1C, a 50/67/83 MVA 230/69/13.8 kv transformer. The final configuration is this substation is KV1B, 30/40/50 MVA, 230/69/13.8 kv and KV1C. KV1A, 18/24/30 MVA, 230/69/13.8 kv will eventually be removed from the Badwater Substation. The 69 kv bus will continue to be operated open. Reference Attachment A. 2. The addition of KV4A, a 50/67/83 MVA 230/69/13.8 kv transformer and the replacement of KV1A with a 50/67/83 MVA 230/69/13.8 kv transformer. The KV1B, 30/40/50 MVA, 230/69/13.8 kv transformer is connected to the 69 kv bus. 69 kv bus can be operated closed. Reference Attachment B. 3. Replacement of KV1A and KV1B with 2 90/120/150 MVA, 230/69/13.8 kv transformers. The 69 kv bus can be operated closed. Reference Attachment C. Badwater Substation is located in Fremont County, Wyoming. Presently, Western owns KV1A and the Customer s Member owns KV1B. Western has operational and maintenance responsibilities for all equipment in this substation. Operational, maintenance and replacement financial responsibilities are contractually aligned with ownership. Rebuilding of the 69 kv transmission lines is not a part of this facility study. The projected loads have been provided by the Customer s Member consultant. Transformation alternatives are provided to support present and projected loads. The total projected load within the coming year is 76 MVA. The projected five year plan includes the addition of a 20 MVA substation and a 25 MVA CO 2 plant, to be served from the Badwater Substation. So the total projected load is 100 MVA in five years. This study includes the physical substation modifications as well as how each configuration meets the strategic requirements and operational objectives. Strategic requirements include capacity to support the existing and projected loads, without outages, to perform routine maintenance. Operational objectives include maintaining the contracted voltage level regardless of the 69 kv bus switch configuration and without compromising TOT4B. Page 1 of 12
II. Project Description Alternative 1: The addition of KV1C 50/67/83 MVA, disconnect 69 kv terminals of KV1A (Reference Attachments A) 230 kv Work: The work includes 230 kv transformer bus structure additions and modifications. Provide associated instrument transformers and protection and control equipment. Equipment includes: Disconnect Switch, WV1D Power Circuit Breaker, JV1A 3 CCVT, W1B 69 kv Work: The work includes 69 kv transformer bus structure additions and modifications The bus will be overbuilt for height for the removal of KV1A. Provide associated equipment for revenue metering as well as associated protection and control equipment. Equipment includes: Disconnect switch,wz4a QZ4A Current Transformer VZ4A Potential Transformer 13.8 kv Work: This work includes equipment required for connection to station service in place of the existing KV1A tertiary winding. Equipment includes: Fused Disconnect Switch FW1C Disconnect Switch WW1C Transformer KV1C Work: Specification and procurement will be provided by the Customer. Commissioning services will be provided by Western as well as construction contract administration. The construction contract includes: Foundation placement Bus connections Structures for CT s, PT s, Revenue metering Miscellaneous control cabling from transformer to control building. Modifications to the oil containment structure. Operational Understanding: Construct the addition of transformer KV1C in such a manner that transformer KV1A remains in service until KV1C is energized, tested and loaded. Once transformer KV1C is operational, Western will decide whether to leave transformer KV1A in place as a backup or remove it for use at another substation. Strategic Requirements and Operational Objectives: This alternative does not satisfy the reliability requirement for equipment maintenance. For routine maintenance, the Page 2 of 12
83 MVA transformer cannot be taken out of service without a reduction in load. Presently, the load exceeds the capacity of the 50 MVA KV1B. At the five year time period, the 50 MVA will not be able to be taken out of service for routine maintenance as the 83 MVA will not be able to support the projected load. The bus may be operated open or closed. Operated closed, the 69 kv bus voltage is at the per unit (p.u.) lower limit. Sustained under voltage reduces equipment life, increases motor slip and presents motor starting difficulties. Alternative 2: The replacement of KV1A with a 50/67/83 MVA and the addition of KV4A 50/67/83 MVA (Reference Attachment B) 230 kv Work: The works includes the construction of a new 230 kv transformer bus structure, and extensive additions and modifications to the existing 230 kv bus. Provide associated instrument transformer and protection and control equipment. Equipment includes: A new 230 kv bay: 2 Disconnect switches YV4A, YV3A, one PCB JV4A Relocation of the takeoff structure and CCVT W4A from bay 4 to bay 2 for reliability 230 kv new bus to second 83 MVA transformer will require the north fence to be moved 40 north. The construction contract will include yard grading, fence work and extending the ground mat. 69 kv Work: This work includes additions and modifications to the 69 kv bus structure. 69 kv turning structure Disconnect switches WZ7A, WZ7B, WZ2C Power Circuit Breaker JZ7A Potential and current transformers VZ7A, QZ7A, QZ2A 13.8 kv Work: This work includes equipment required for connection to station service in place of the existing KV1A tertiary winding. Disconnect the tertiary service from KV1B. Station service will be provided by KV1A and KV4A. Equipment includes: Fusible Disconnect Switch FW4A Transformer KV1A Work: Specification and procurement will be provided by the Customer. Commissioning services will be provided by Western as well as construction contract administration. The construction contract includes: Existing foundation demolition and removal. Decommission the existing 30 MVA and move to cribbing in the yard. New foundation placement Structures for CT s Revenue metering Miscellaneous control cabling. Page 3 of 12
Modifications to the existing oil detention structure. Transformer KV4A Work: Specification and procurement will be provided by the Customer. Commissioning services will be provided by Western as well as construction contract administration. The construction contract includes: Demolition and removal of foundation New foundation placement Structures for CT s, PT s Revenue Metering Miscellaneous control Provision of an additional oil detention structure. Operational Understanding: Construct the addition of transformer KV4A in such a manner that transformer KV1A remains in service until KV4A is energized, tested and loaded. Once transformer KV4A is operational, remove the 30 MVA transformer from service and decommission. Install new foundation for 83 MVA KV1A and commission. This alternative has the additional complexity of relocating the bay that protects the Thermopolis 230 kv transmission line. Outages will be required for this work. Strategic Requirements and Operational Objectives: This alternative does satisfy the reliability requirement for maintenance on any of these transformers. The bus may be operated open or closed. Operated closed, the 69 kv bus voltage is at the lower limit for this alternative. Sustained under voltage reduces equipment life, increases motor slip and presents motor starting difficulties. In this alternative, the voltage drop at the bus is a function of the lower capacity transformer impedance. Moreover, the loss of the Badwater Spence line creates an unacceptable voltage drop at this bus. As reported in the system impact study, for Alternative 2, voltages stay within acceptable operational limits for system intact and all contingency scenarios studied. However, future operating conditions as modeled in a Western Electricity Coordinating Council (WECC) 2015 heavy summer base case demonstrate unacceptable voltage drop. This is due to regional load increases, the projected ultimate load for Lost Cabin facilities, and topology changes. The result is low voltage on the 69 kv system emanating from Badwater for certain N 1 contingencies. This unacceptable low voltage persists after planned transmission line upgrades such as re conductoring the line to the Gas Plants 1 and 2 with 795 kcm. 1 Alternative 3: The replacement of KV1A and KV1B with two 90/120/150 MVA transformers (Reference Attachment C ) 230 kv Work: The work includes modifications to the 230 kv bus. CCVT W1B1 1 WAPA RMR Planning Engineering, " System Impact Study 2009 T1 Transformer Replacement at Badwater Substation," (July 2010): p.7. Page 4 of 12
69 kv Work: This work includes modifications to the 69 kv bus. Disconnect switches, WZ1C, WZ4A Current transformers, Potential Transformers QZ1A, QZ4A,VZ4A 13.8kV Work: This work includes connecting into existing station service equipment. Station service will be provided by KV1A and KV1B. Equipment includes: Disconnect switch WW1A Fusible disconnect switch FW1A Transformer KV1A and KV1B Work: Specification and procurement will be provided by the Customer. Commissioning services will be provided by Western as well as construction contract administration. The construction contract includes: Two foundations demolition and removal Two new foundation placement Structures for CT s, PT s Revenue Metering for each Miscellaneous control and protection scheme modification. Modifications to the existing oil detention structure. A second oil detention structure. Operational Understanding: Install, test, energize the new KV1A. Once the 150 MVA KV1A is operational, decommission the existing KV1A and KV1B. Move to cribbing in the yard as spares. Demolish and remove existing foundations. Place new foundation. Install, test and energize KV1B. Strategic Requirements and Operational Objectives: This alternative satisfies the reliability requirement for maintenance on either of these transformers. Operationally, the bus may be open or closed. Operated closed, the 69 kv bus voltage is well above the lower limit, but not at unity for this alternative III. Western s Requirements Western will provide project management, procurement, field data, design, construction contract administration, construction inspection, commissioning, lands, contracts, environmental, station equipment energization, and installation of transformer configuration and related equipment for the installation at Badwater Substation. The Customer will provide and install the 69 kv revenue metering for the new Transformer(s). Page 5 of 12
The Customer will specify and procure the transformer(s) at their cost. Western will install and commission the transformer(s). A revised facility agreement between Western and the Customer will be required. Western will require funds equal to the estimated design and construction contract cost of the project scope as defined in Table 1, 2, or 3 for Alternative 1, 2, or 3 respectively prior to the commencement of work. The preliminary schedule, Table 4, has proposed milestones for design and construction activities as well as funding. Western s project scope as described above will be confined to that work directly related to the Badwater Substation. All other work outside of the Badwater Substation such as the construction or modification of additional 69 kv transmission lines or distribution substations to serve the additional loads will be the responsibility of the Customer s Member. Page 6 of 12
IV. Cost Alternative 1 Western s estimated cost for the addition of an 83 MVA power transformer (KV1C) at Western s Badwater Substation is $2,335,800. Please refer to Table 1 for a cost estimate breakdown. This budgetary cost estimate includes project management, field data, design, construction inspection, construction, commissioning, lands, contracts, environmental, station equipment protection and cabling and 69 kv revenue metering for the addition of a new 230/69/13.8 kv, 83 MVA power transformer (KV1C) at Western s Badwater Substation. Table 1 Badwater Substation Addition of 230/69kV, 83 MVA Transformer Cost Estimate TASK DESCRIPTION COST Project Management $25,000 Field Data $20,000 Design $260,000 Construction Inspection $155,000 Construction Contract $1,460,000 Commissioning $120,000 Miscellaneous 10% (Contingency) $204,000 Inflation(3%/year and late 2011 award = 4.5% $91,800 Western TOTAL: $2,335,800 Transformer: $1,163,755 Total Project Cost: $3,499,555 Note: Cost in Table 1 does not include revenue metering equipment. Page 7 of 12
Alternative 2 Western s estimated cost for the replacement of the 30 MVA transformer with an 83 MVA transformer and the addition of a third 83 MVA transformer at Western s Badwater Substation is $3,104,095. Please refer to Table 2 for a cost estimate breakdown. This budgetary cost estimate includes project management, field data, design, construction inspection, construction, commissioning, lands, contracts, environmental, station equipment protection and cabling, and 69 kv revenue metering for the addition of two new 230/69/13.8 kv, 83 MVA power transformers (KV1A and KV4A) at Western s Badwater Substation. Table 2 Badwater Substation Addition of 2 230/69kV, 83 MVA Transformers Cost Estimate TASK DESCRIPTION COST Project Management $25,000 Field Data $20,000 Design $330,000 Construction Inspection $220,000 Construction Contract $1,916,000 Commissioning $200,000 Miscellaneous 10% (Contingency) $271,100 Inflation(3%/year and late 2011 award = 4.5% $121,995 Western TOTAL: $3,104,095 Transformers: $2,141,505 Total Project Cost: $5,245,600 Note: Cost in Table 2 does not include revenue metering equipment. Page 8 of 12
Alternative 3 Western s estimated cost for the replacement of the 30 MVA (KV1A) transformer and the 50 MVA ( KV1B) transformer with 2 150 MVA transformers at Western s Badwater Substation is $1,976,270. Please refer to Table 3 for a cost estimate breakdown. This budgetary cost estimate includes project management, field data, design, construction inspection, construction, commissioning, lands, contracts, environmental, station equipment protection and cabling, and 69 kv revenue metering for the addition of two new 230/69/13.8 kv, 150 MVA power transformers (KV1A and KV1B) at Western s Badwater Substation. Table 3 Badwater Substation Addition of 2 230/69/13.8 kv, 150 MVA Transformers Cost Estimate TASK DESCRIPTION COST Project Management $25,000 Field Data $20,000 Design $240,000 Construction Inspection $155,000 Construction Contract $1,136,000 Commissioning $150,000 Miscellaneous 10% (Contingency) $172,600 Inflation(3%/year and late 2011 award = 4.5% $77,670 Western TOTAL: $1,976,270 Transformers: $3,114,300 Total Project Cost: $5,090,570 Note: Cost in Table 3 does not include revenue metering equipment. Page 9 of 12
V. Schedule The following preliminary project schedule is based on a one year manufacture and delivery time for transformer(s). The following schedule does not include delays due to inability to take necessary outages to perform construction work when required. Table 4 Preliminary Project Schedule Activity Start Completion Facility Agreement October 2010 October 2010 Partial Receipt of Funds Pre Design Activities October 2010 October 2010 Planning/Field Data Funding October 2010 October 2010 Planning/Field Data October 2010 January 2011 Transformer Specification/Procurement October 2010 October 2010 Process Funding (Customer) Transformer(s) Specification (Customer) November 2010 January 2011 Western Design Funds January 2011 January 2011 Transformers Procurement (Customer) January 2011 July 2011 Outdoor Electrical Design and Specifications March 2011 May 2011 Revenue Metering Procurement (Customer) September 2011 February 2012 Equipment Purchase/Manufacture/Delivery September 2011 February 2012 Western Construction Funds April 2011 April 2011 Construction Contract Development June 2011 August 2011 Award Construction Contract August 2011 August 2011 Construction September 2011 March 2012 Construction Supervision Funding January 2012 January 2012 Construction Supervision February 2012 May 2012 Commissioning Funding January 2012 January 2012 Commissioning March 2012 May 2012 In Service May 2012 May 2012 Page 10 of 12
Table 5 Preliminary Project Schedule and Funding Requirements for Alternative 3 Activity Start Completion End User Funding Required Facility Agreement Oct 10 Oct 10 Partial Receipt of Funds Pre Design Oct 10 Oct 10 Activities $30,000 Planning/Field Data Funding Oct 10 Oct 10 $172,600 Planning/Field Data Oct 10 Jan 11 Transformer Specification Funding Oct 10 Oct 10 (Customer) Transformer(s) Specification (Customer) Nov 10 Jan 11 $155,715 Western Design Funds Jan 11 Jan 11 $240,000 150 MVA Transformer Procurement #1 Jan 11 Jul 11 (Customer) Funding over 3 quarters $1,557,150 150 MVA Transformer Procurement #2 Jan 11 Jul 11 (Customer) Funding over 3 quarters $1,557,150 Outdoor Electrical Design and Mar 11 May 11 Specifications Revenue Metering Procurement Sep 11 Feb 12 (Customer) $200,000 Ancillary Equipment Sep 11 Feb 12 Purchase/Manufacture/Delivery Western Construction Funding April 11 April 11 $1,228,670 Construction Contract Development Jun 11 Aug 11 Award Construction Contract Aug 11 Aug 11 Construction Sep 11 Mar 12 Construction Supervision Funding Jan 12 Jan 12 $155,000 Construction Supervision Feb 11 May 12 Commissioning Funding Jan 12 Jan 12 $150,000 Commissioning Mar 12 May 12 In Service May 12 May 12 Total $5,446,285 Page 11 of 12
ATTACHMENT A Proposed Switching Diagram and Arrangement Plan for Badwater Substation Alternative 1 Addition of one 83 MVA Transformer (KV1C) 30 MVA (KV1A) - secondary disconnected 50 MVA (KV2A)
ATTACHMENT B Proposed Switching Diagram and Arrangement Plan for Badwater Substation Alternative 2 Addition of two 83 MVA Transformers (KV1A & KV4A) 50 MVA (KV2A)
ATTACHMENT C Proposed Switching Diagram and Arrangement Plan for Badwater Substation Alternative 3 Addition of two 150 MVA Transformers (KV1A & KV1B)