OVERALL EXTERNAL SERVICES COSTS

Transcription

1 EB Tab Schedule Filed: 00 Aug Page of OVERALL EXTERNAL SERVICES COSTS INTRODUCTION THESL uses external services to complement its internal capacity to execute work programs. External services represent those services that are generally not available internally. External Services are procured through long term (three- to five-year) services agreements negotiated with a select group of reliable, cost competitive, customer focused service providers in accordance with the Toronto Hydro Procurement Policy guidelines. The contracts are reviewed annually and structured to drive continuous improvement through cost reduction initiatives and the implementation of value added services. EXTERNAL SERVICES BENEFITS allows THESL to focus on core competencies; reduces the need to hire and train specialized staff that may be needed only on an occasional basis; reduces capital expense on fleet, equipment and facilities; and allows THESL to reduce and control operating costs particularly where internal options are less efficient. 0 EXTERNAL SERVICES The following is a summary of key external services: Civil Construction Vegetation Management Wood Pole Inspection and Treatment Vacuum Truck Services Insulator Washing Transformer & Cubicle Haulage

2 EB Tab Schedule Filed: 00 Aug Page of Underground Infrared Inspection Overhead Infrared Inspection Carbon dioxide (CO ) Cleaning Submersible Vault Washing Transformer and Cable Chamber Washing 0 Civil Construction Civil Construction encompasses the construction of all civil infrastructure related to THESL's capital investment program as well as the repair and rehabilitation of existing civil assets. Although age is loosely related to the condition of underground civil structures, it is not a linear relationship. Other factors such as mechanical loading and exposure to corrosive salts have a more substantial effect. Some underground cable chambers may only need cleaning or minor repairs i.e., frames, covers, vault doors, grates, etc., while others may require major structural repairs or rebuild to the walls, floor and roof. When prioritizing the replacement of civil infrastructure, capacity planning issues and City-mandated plant relocations are also taken into consideration. Cable chamber degradation commonly includes corrosion of reinforcing steel, spalling and flaking of the concrete, and rusting of covers or rings. Acidic salts (i.e., sulfates or chlorides) affect corrosion rates. Cable chamber systems also may experience a number of deficiencies or defects. In roadways, defects exist when covers are not level with street surfaces. Conditions that lead to flooding, clogged sumps, and non-functioning sump-pumps also represent major deficiencies in a cable chamber system. The overall condition of underground chambers is ranked by taking into account the following factors: Condition of floors, walls and roof; Existence of asbestos tapes; Condition of cable racks;

3 EB Tab Schedule Filed: 00 Aug Page of Existence of flooding; Condition of drain and sump pump; Dimensions and available working space; and Infra-red scan of splices. The average life of underground chambers is in the order on 0 to 0 years. When comparing the number of units to be replaced over the next ten years, the Asset Condition Assessment and the age-based model produced different results. The condition-based analysis was believed to provide more realistic results because civil structures in areas not exposed to corrosive, caustic and alkaline environments can last substantially longer than an age-based assessment would indicate. Vegetation Management The Vegetation Management ( VM ) program is a reliability improvement initiative. Overhead distribution systems are prone to tree branch contacts resulting in feeder outages. To reduce the frequency and impact of tree contacts, a VM program is used to maintain adequate clearance between tree branches and overhead conductors. 0 Proper pruning of tree branches along overhead distribution routes serves to ensure that tree branches will not grow into THESL s power lines. Good vegetation management also prevents brush contacts thereby reducing outage frequency during normal weather conditions. Past reliability data have shown that the continued use of a vegetation management program significantly reduces the number of tree related outages. Some areas of the city such as the former Toronto district may require more funding for the VM program due to a higher density and more mature tree population. THESL s reliabilitybased vegetation management efforts are discussed in Exhibit F, Tab, Schedule. The goal is to implement a feeder-based management program to address the current increase in tree-related outages and gradually reduce the trend during the next three years.

4 EB Tab Schedule Filed: 00 Aug Page of Wood Pole Inspection/Treatment Scheduled inspection of wooden poles for decay reduces the risk of exposure to failure, enhances the reliability of the system, and reduces expenditures for capital replacement. It has been determined that the service life of poles with internal and/or external decay can be extended by applying sealants and treatments designed to combat decay and arrest any further degradation of the pole. This program extends the useful lifespan of THESL s pole assets. Other utilities that have been on a ten-year cycle of testing and treatment have achieved a reduction in wooden pole replacements ranging from greater than six percent to less than one percent. The pole inspection and treatment program also allows THESL to prioritize its Capital replacement program based on the test results received. In addition, the program allows THESL to identify poles that may present a safety risk to the public. 0 Vacuum Truck Services Vacuum Truck Services is a reactive type of service used to remove contaminated water/liquid waste from transformer vaults and cable chambers as required. Cable chambers and transformer vaults located in the sidewalk or roadways are regularly subjected to dirt and contamination ingress, including nitrogen compounds from vehicle exhaust, household and commercial liquid waste. Contaminant deposits build up over time resulting in flooding and damage to cable and equipment. A periodic wash and vacuuming program is required to ensure that the equipment and the surrounding containment area are properly maintained to provide for optimal operating conditions.

5 EB Tab Schedule Filed: 00 Aug Page of Insulator Washing Services Regular insulator washing removes summer dirt and winter salt that accumulate over time. This dirt and salt, combined with moisture, reduces insulation levels and leads to tracking, resulting in flashovers and pole fires. Statistics of insulator failure at THESL over the last three years show an average of: ) line insulator failures per year with customer hours per failure; ) lightning arrestor failures with customer hours per failure; and ) pole top transformer failures with customer hours per failure. In addition to line insulators, this program includes the washing of all switches, arrestors, terminators, transformer bushings and other circuits which may exist on the pole. The program is expected to result in reduced power line outages from electrical tracking. Transformer & Cubicle Haulage The Transformer & Cubicle Haulage service primarily supports facilities operations and warehouse material handling requirements including moving/relocation of transformers, switchgear cubicles, roof-top equipment and materials within THESL s service area. 0 Underground Infrared Inspection It is essential to inspect and maintain the cable chambers routinely in order to improve underground system reliability and reduce the cost for post fault cable replacement. Reliability data show an annual average (over the last three years) of 0 splice failures, pothead failures and 0 leaking PILC cables.

6 EB Tab Schedule Filed: 00 Aug Page of Overhead Infrared Inspection Infrared inspection of overhead line components identifies potential hot spots and allows for corrective measures to be taken before they have an impact on system reliability. Electrical connections may become loose after some time as a result of load cycling, contamination and physical fatigue. When the connection becomes loose, oxidation penetrates the connection surfaces. This oxidation offers resistance to the flow of electricity creating a hot spot at the point of contact. As a result, the connector will gradually melt and the line will become disconnected. Infrared scanning of the overhead plant detects these hot spots and allows THESL to take corrective action under a controlled condition rather than respond to an unexpected power outage. 0 CO Cleaning The CO Cleaning service involves the cleaning of pad-mounted switches, which are typically installed on. kv feeders. This service work constitutes a reactive follow-up to the infrared inspection of pad-mounted switches, where the need for CO cleaning is identified at hot spots. This program supports THESL s reliability initiatives to reduce/eliminate outages caused by flashed-over, porcelain insulators within PMH switchgear. Submersible Vault Washing Submersible vaults are smaller distribution vaults containing transformers and switches. They are typically installed below sidewalks and in boulevards with ventilation grills and consequently are prone to dirt and leaf build-up, which can clog the vault drainage system. They are pressure washed to maintain equipment performance and system reliability.

7 EB Tab Schedule Filed: 00 Aug Page of Transformer and Cable Chamber Washing Transformer vaults are larger distribution vaults typically installed below sidewalks in the downtown core and along Yonge Street and the Bloor/Danforth corridor. Cable chambers are installed along most roadways to facilitate underground cabling. Transformer and cable chamber washing is both a reactive type of service, and part of planned work. In advance of planned cable work, equipment replacement or maintenance, cleaning may be required to support effective crew activity. On a reactive basis, vaults and chambers may require cleaning as part of a post-fire clean-up or remediation activity. SERVICE COSTS Table : Total External Service Costs ($000) Service 00 Historical 00 Bridge 00 Test 00 Test 0 Test Civil Construction,00,00 0,00,00,000 Vegetation Mgt,0,00,00,00,00 Wood Pole Inspection Vacuum Truck Services Insulator Washing Transformer Haulage Infrared Inspection OHD/UG CO Cleaning Vault Washing 0 Transformer Washing Total,000 0,000,000,000,000

8 EB Tab Schedule Filed: 00 Aug Page of Civil Construction - Variance On a year-over-year basis, the capital requirements for civil construction increase by $. million in 00, by $. million in 00, by $. million in 00, and by a further $. million in 0. The investment in civil construction services over the period 00-0 aligns with the civil infrastructure required to support the capital investment program. Vegetation Management Variance Vegetation Management program costs increased by $.M between 00 and 00 to reduce the increased potential of tree-related outages. In 00, THESL engaged Davies Consulting Inc. to develop a Vegetation Management Model to address increased treerelated outage events. This model fosters a more analytical method to determine vegetation management requirements and supports THESL s increased investment. The years 00 through to 0 represent a consistent investment on a year-over-year basis to align with the requirements of this model. The model takes into account several factors including storm-related outages, increased tree planting in the City, customer aversion to tree-trimming, and municipal regulations related to tree-trimming. 0 Wood Pole Inspection Variance The 00 budget for this program was $K, with only $K spent. Six thousand poles were inspected/treated in 00, as prescribed. However, fewer poles required treatment (to address decay) in 00. This program remains relatively stable throughout the bridge and test years, with only minor variations in the number of poles being inspected each year. There is an expectation that THESL will need to treat more poles in the coming years to delay the progression of decay. Vacuum Truck Services Shows no significant variance 00-0.

9 EB Tab Schedule Filed: 00 Aug Page of Insulator Washing Variance A late start in the 00 program resulted in an increase in insulator flash-overs. A return to more typical expenditures for the annual insulator washing program is represented from 00 through 0. Transformer Haulage Shows no significant variance Infrared Inspection Overhead and Underground Variance These three programmes are being combined into one contract. The increase in spending reflects the transition of the overhead three-phase line and PMH switch inspections from internal service providers to external contractors. CO Cleaning Shows no significant variance. Vault Washing Shows no significant variance. Transformer Washing Shows no significant variance.