FINAL FACILITY STUDY KV1C Transformer Addition at Badwater Substation 2009-T1 November 17, 2009
I. Introduction In October 2008, Western Area Power Administration (Western) received a Transmission Queue Request 2009-T1. On August 21, 2009, Western, the Customer, and the Customer s Member altered the scope of the Badwater Substation Transformer Addition Project. The proposed transformer rating increased from 50 MVA to 83 MVA. This modification is for additional loads, a future compression station and CO2 plant, to be served from the Badwater Substation. Badwater Substation resides in Fremont County, Wyoming and is presently owned, operated and maintained by Western. The new 69-kV loads will be served by modification and equipment additions in the Badwater Substation. Currently, the Badwater Substation has two 230/69/13.8-kV transformers: Transformer KV1A (18/24/30 MVA Western owned) and KV1B (30/40/50 MVA Customer owned). The Customer s Member requests replacement of KV1A with a third transformer which will be designated, KV1C. The in-service date for KV1C is expected to be within first calendar quarter of 2011. The rating of KV1C will be 50/67/83 MVA. The Customer s Member forecasts 23 MW of load, in addition to the existing 47 MW of load. The combination of the existing and new load gives a total of 70 MW load being served by Badwater Substation. Portions of the two existing 69-kV transmission lines serving Lost Cabin Gas Plant Phase III substation and Lost Cabin Gas Plant 1 & 2 may be rebuilt by the Customer s Member. The transmission line rebuild is not a part of this facility study or the Badwater Substation project. In October 2009, Western performed a second System Impact Study (SIS) to determine if there are any system criteria violations on the Wyoming power grid caused by the proposed 23 MW of additional load. The requested load increase presents no operating violations to voltages at Western s Badwater 230 kv bus 1. A switchyard expansion is not anticipated for this additional transformer and ancillary equipment. Modifications to the oil detention basin, part of the spill containment plan, may be modified as KV1C information becomes available. II. Project Description 230-kV Work: The addition of transformer KV1C at Badwater Substation will include, but is not limited to the construction of a new 230-kV transformer bus structure, additions and modifications of the 230-kV bus, a 230-kV interrupter with one fused disconnect switch, installation of associated instrument transformers, and associated protection and control equipment. 1 WAPA RMR Planning Engineering, " System Impact Study 2009-T1 Transformer Replacement at Badwater Substation," (October 2009): p.5. Page 1 of 5
69-kV Work: The addition of transformer KV1C at Badwater Substation will include, but not limited to additions and modifications to the 69-kV transformer bus structure, disconnect switch, associated protection, control equipment and boundary metering. (see Attachment A). The substation station service, currently served by the tertiary of KV1A, will be served by the KV1C tertiary. Transformer KV1C Work: Provision of a foundation, a metering structure for CT s, PT s, revenue metering, miscellaneous control cable and station service power through the cable trench. Operational Understanding: Construct the addition of transformer KV1C in such a manner that transformer KV1A remains in service until the cut over to transformer KV1C. Once transformer KV1C is energized, Western will decide whether to leave transformer KV1A in place as a backup or remove for use at another substation. (See Attachment B) III. Western s Requirements Western will provide project management, field data, design, construction contract administration, construction inspection, commissioning, lands, contracts, environmental and station equipment and installation of transformer KV1C and related equipment for the installation at Badwater Substation. The Customer will provide and install the 69-kV revenue metering for the new transformer. The Customer s Member will purchase the transformer KV1C at their cost. Western will install and commission KV1C. An agreement between Western and the Customer s Member will be required. Western will require funds equal to the estimated cost of the project scope as defined in Table 2 prior to the commencement of work. 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 including any construction or modification of additional 69kV transmission lines and distribution substations to serve the additional load will be the responsibility of the Customer s Member. Page 2 of 5
IV. Schedule The following preliminary project schedule is based on a one year manufacture and delivery time for transformer KV1C. The following schedule does not include delays due to not being able to take necessary outages to perform construction work when required. Please refer to Table 1. Table 1 Preliminary Project Schedule Activity Start Completion Facility Agreement August 2009 October 2009 Agreement Development October 2009 December 2009 Agreement Execution January 2010 Receipt of Funds January 2010 Planning/Field Data January 2010 March 2010 Design and Specifications February 2010 May 2010 Equipment Purchase/Manufacture/Delivery February 2010 April 2011 Construction Contract Development June 2010 July 2010 Award Construction Contract August 2010 Construction September 2010 March 2011 Commissioning March 2011 May 2011 In Service May 2011 Page 3 of 5
V. Cost Western s estimated cost for the addition of power transformer (KV1C) at Western s Badwater Substation is $2,630,000. 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 and 69-kV revenue metering for the addition of a new 230/69kV, 83 MVA power transformer (KV1C) at Western s Badwater Substation. Table 2 Badwater Substation Addition of 230/69kV, 83 MVA Transformer Cost Estimate TASK DESCRIPTION COST Project Management $25,000 Field Data $20,000 Design $225,000 Construction Inspection $155,000 Construction Contract $866,000 Commissioning $100,000 Miscellaneous 10% (Contingency) $139,100 Inflation(3%/year and late 2010 award = 4.5% $62,595 TOTAL: $1,592,695 Note: Cost in Table 2 does not include cost of the customer provided transformer KV1C or revenue metering equipment. Page 4 of 5
ATTACHMENT A Proposed Switching Diagram for Badwater Substation
ATTACHMENT B Proposed Arrangement Plan for Badwater Substation