Project Need: Discretionary: Improve transfer capability between Ontario and Québec. IPSP Reference: Non-IPSP
Hydro One Networks – Investment Summary Document
Investment Type: Inter-Area Network Transfer CapabilityReference # Investment Name Gross Cost In-Service Date
D2 New 500kV Bruce to Milton Double Circuit Transmission Line $619.8M Mid 2010/Late 2011 Please see Exhibit D1, Tab 3, Schedule 3, Table 2 for cash flow and other details about each project.
Need:
To construct a new double-circuit 500kV line between Bruce and Milton in accordance with the Ontario Power Authority (“OPA”) recommendation; to address the inadequate transmission capacity to transmit committed renewable and baseload generation in Bruce Area to the load in southern Ontario (as per deliberations during Proceeding EB-2007-0050 for the Bruce to Milton 500kV project). Not proceeding with this investment would result in the constraint of nuclear and renewable generation in the Bruce Area.
Summary:
The existing transmission in southern Ontario cannot accommodate the generation expected to come into service in the Bruce area over the next few years. This includes:
• 1500MW from upgrades of existing facilities and rehabilitation and restart of Bruce A units G1 and G2, for which OPA has assumed a contract between the Ministry of Energy and Bruce Power Inc.
• 1700MW from new wind generation in the Bruce area, including an aggregate of 723MW for which the OPA has entered into contracts with wind developers, through the Ministry of Energy’s Request For Proposals. To incorporate the above generation into the transmission system, additional transmission capability is required. The OPA has determined that the preferred solution to increase the transfer capability of Hydro One’s 500kV system is to build a new 500kV double circuit transmission line between Bruce Complex and Milton SS to securely incorporate all eight units from Bruce and the committed and potential wind generation.
The OPA has urged Hydro One to initiate the activities required to construct the new 500kV line for in-service by December 2011. The activities noted include "acquiring the required permits, regulatory approvals, engineering work and the prudent purchasing of materials needed to meet the required in-service date". The OEB approved Hydro One’s ‘Leave to Construct’ Application in September 2008 (Proceeding EB-2007-0050) and an application for Environmental Assessment Approval has been submitted. The project will be undertaken in two phases to facilitate construction by taking advantage of the availability of transmission outages in 2009 and 2010 as a result of planned outages at Bruce GS. Thus, Phase 1 is scheduled to be in-service in mid-2010 and Phase 2 by December 2011.
The need for this project was identified in the IESO’s December 2007 Ontario Reliability Outlook, and an IESO System Impact Assessment Report (CAA ID 2006-250) has been completed for this project. The Ontario Government has also, in its announcement of “A Balanced Plan for Ontario’s Electricity Future”, reiterated the need for “expanding the transmission capacity from Bruce County and surrounding area to facilitate the transmission of electricity from several new wind farms and the Bruce facility”.
Results:
Provide sufficient transmission capacity to reliably transmit the output of the Bruce GS and 1700MW of wind generation in Bruce and surrounding counties in accordance with Northeast Power Coordinating Council criteria. Project Classification per OEB Filing Guidelines / IPSP Status:
Project Class: Development
Project Need: Non-Discretionary: The project is required to satisfy the recommendations outlined by the OPA to accommodate new generation.
IPSP Reference: Pre-IPSP: This project was referenced in the IPSP Discussion Document (November 13, 2006) and/or in the IPSP (August 29, 2007) on the basis that, in order to meet the required need date, the project would be initiated by Hydro One prior to IPSP approval.
Hydro One Networks – Investment Summary Document
Investment Type: Inter-Area Network Transfer Capability
Reference # Investment Name Gross Cost In-Service Date
D3 Install Seven 230kV Capacitor Banks in Southwestern Ontario $56.5M Late 2009 Please see Exhibit D1, Tab 3, Schedule 3, Table 2 for cash flow and other details about each project. Need:
To comply with the recommendation of the Ontario Power Authority (“OPA”) to install seven 230kV shunt capacitor banks at three stations in southwestern Ontario in 2009 as a near-term measure to increase transfer capability in the Bruce Area and southwestern Ontario (as per deliberations during Proceeding EB-2007-0050 for the Bruce to Milton 500kV project).
Not proceeding with this investment would result in increased amounts of constrained nuclear and wind generation starting in 2009.
Summary:
The OPA has recommended that Hydro One Networks proceed with the installation of seven capacitor banks: one 230kV 200MVar at Buchanan TS, four 230kV 250MVar at Middleport TS and two 230kV 250MVar at Nanticoke TS for in-service in 2009. The installation of these facilities is one of the measures required to increase the transfer capability of the Bruce and southwestern Ontario transmission systems to accommodate the delivery of 1500MW of additional generation at Bruce A nuclear plant and the 1700MW of committed and potential wind generation developments in the Bruce area.
The capacitor bank installations will include additional measures that were identified in the investigation of an explosion of the 230kV Richview TS capacitor bank on January 30, 2007 in order to address the cause of the failure. These additional measures include installation of the following:
• Surge capacitors to mitigate the rapid rise of recovery voltage (RRRV) seen by the capacitor bank breakers • Breakers with a better transient recovery (TRV) characteristic
• Capacitor unit insulators with a larger creep to reduce the possibility of insulator flashover
This project was identified in the IESO’s December 2007 Ontario Reliability Outlook and an IESO System Impact Assessment Report (CAA ID 2007-295) that was completed for this project. The increased transmission capacity, provided by the capacitor banks, will also have an enduring benefit after the completion of the proposed Bruce to Milton 500kV transmission line. The new capacitor banks will support the government’s off-coal strategy by replacing some of the voltage control functionality currently provided by Nanticoke GS.
Results:
Increase the transmission transfer capability of the Bruce and southwestern Ontario transmission systems through the installation of seven 230kV shunt capacitor banks as recommended by the OPA.
Project Classification per OEB Filing Guidelines / IPSP Status: Project Class: Development
Project Need: Non-Discretionary: The projects are required to incorporate new generation in Ontario, to satisfy government directive(s), and to satisfy the recommendations outlined by the OPA. IPSP Reference: Pre-IPSP: This project was referenced in the IPSP Discussion Document (November 13, 2006)
and/or in the IPSP (August 29, 2007) on the basis that, in order to meet the required need date, the project would be initiated by Hydro One prior to IPSP approval.
Hydro One Networks – Investment Summary Document
Investment Type: Inter-Area Network Transfer Capability
Reference # Investment Name Gross Cost In-Service Date
D4 Bruce Special Protection System Modifications for Bruce Area $5.8M Mid 2010 Please see Exhibit D1, Tab 3, Schedule 3, Table 2 for cash flow and other details about each project. Need:
To increase generation and load rejection coverage within the Bruce Area as an interim measure in accordance with the Ontario Power Authority (“OPA”) recommendation (as per deliberations during Proceeding EB-2007- 0050 for the Bruce to Milton 500kV project). Implication of not proceeding with this investment includes: outage restrictions impacting Hydro One work program and curtailment of nuclear and wind powered generation in the Bruce Area resulting in increased costs.
Summary:
The Bruce Special Protection System (BSPS) is a collection of special protection systems installed at Bruce NGS and associated stations that perform pre-defined control actions (such as: generation rejection, reactor tripping and load rejection) in response to recognized contingencies in the Bruce area. By providing these capabilities, restrictions on the maximum output of Bruce NGS and other system parameters can be reduced or eliminated, while still respecting the established system criteria for voltage stability and transmission equipment thermal loading.
The transmission capability of the Bruce Area will be at its limit starting in mid-2009. There is an increase of nuclear and wind generation expected in the area post mid-2009, which will cause the transmission capability to be exceeded until the new 500kV line is completely installed in December 2011. In order to help bridge the gap between the return to service of Bruce units and in-service of a new double circuit 500kV line from Bruce to Milton, the OPA is recommending as an interim measure that Hydro One proceed with the work to increase generation and load rejection coverage.
To maximize the transmission capability, the BSPS requires modification to increase the number of contingencies that require the use of generation rejection in the Bruce Area and to add IESO-identified wind generators to the BSPS scheme. The load rejection capability will also be re-activated at thirteen stations to assist with re- preparation of the system following a critical contingency.
This project was identified in the IESO’s December 2007 Ontario Reliability Outlook and an IESO System Impact Assessment Report (CAA ID 2005-222) was completed for this project.
Results:
• Maximize the transmission capability in the Bruce area by modifying the BSPS to increase generation and load rejection coverage as an interim measure until the new 500kV line is in-service.
• The BSPS will provide enduring benefits in the longer term, as it will be armed during contingency conditions thereby minimizing the outage restrictions that would curtail nuclear and wind powered generation in the Bruce Area and impact the Hydro One work program.
Project Classification per OEB Filing Guidelines / IPSP Status: Project Class: Development
Project Need: Non-Discretionary: The project is required to satisfy the recommendations outlined by the OPA to accommodate new generation.
IPSP Reference: Pre-IPSP: This project was referenced in the IPSP Discussion Document (November 13, 2006) and/or in the IPSP (August 29, 2007) on the basis that, in order to meet the required need date, the project would be initiated by Hydro One prior to IPSP approval.
Hydro One Networks – Investment Summary Document
Investment Type: Inter-Area Network Transfer Capability
Reference # Investment Name Gross Cost In-Service Date
D5 Claireville TS x Cherrywood TS: Unbundle 500kV Circuits $107.3M Late 2010 Please see Exhibit D1, Tab 3, Schedule 3, Table 2 for cash flow and other details about each project. Need:
Reduce need to limit generation east of Toronto and imports from Hydro Québec for 500kV system contingencies and improve the reliability of the Ontario Bulk Electricity System. The implications of not proceeding with this investment include: limiting power transfers from eastern Ontario, exposing Darlington GS to the risk of unscheduled power reductions, and increasing operational risks during outages of 500kV circuits or when elements are out-of-service at Cherrywood TS.
Summary:
The existing 500kV transmission lines between Cherrywood TS and Claireville TS consist of two 500kV double circuit tower lines. The circuits on the north tower line are joined together and operated as a single “super circuit” C551V. Similarly the circuits on the south tower line are joined together and operated as a single circuit C550V. Under outage conditions when one of the two circuits is out-of-service (due to either forced or planned outage), generation connected to the 500kV system in eastern Ontario is curtailed to prevent excessive flows on the 230kV network should a contingency occur. This generation curtailment increases the risk to the reliability of the Bulk Electricity System. The new 1,250MW interconnection with Hydro Québec, 550 MW Portlands GS, and 198 MW Wolfe Island Wind Generation will further increase flow across the Cherrywood TS x Claireville TS 500kV interface. The proposed replacement of Lennox GS with gas-fired units, as per the IPSP, and the proposed development of Darlington “B” GS will also further increase flow across this interface. As a result, potential loss of the interface, or element(s) of the interface, will have a corresponding greater impact since greater amount of generation would be affected. (Additional details about the cost and benefits of this project are provided in Section 3.1.2 of Exhibit D1, Tab 3, Schedule 3).
In order to improve the reliability of the Bulk Electricity System, to provide greater operating flexibility, and to reduce the adverse impact on supply to customers, it is proposed to unbundle the two ‘super’ circuits. This will effectively result in two additional 500kV circuits between Cherrywood TS and Claireville TS. New 500kV terminations will be required at both Cherrywood TS and Claireville TS to accommodate the new circuits. The project also includes work to correct existing deficiencies at Cherrywood TS and Claireville TS. At Cherrywood TS, four 500kV air blast circuit breakers will be replaced with SF6 type breakers. At Claireville TS, a new 500kV GIS breaker will be installed to allow autotransformer T13 to be isolated without having to take one of the two main 500kV buses out-of-service.
This project was identified in the IESO’s December 2007 Ontario Reliability Outlook and the IESO has completed the System Impact Assessment Report (CAA ID 2006-297) for this project.
Results:
Improve transfer capability across the Cherrywood TS x Claireville TS interface and improve reliability of the Bulk Electricity System.
Project Classification per OEB Filing Guidelines / IPSP Status: Project Class: Development
Project Need: Partially Discretionary: Improve transfer capability from generation east of Toronto (Refer to Exhibit D1-3-3, Section 3.1.2).
Hydro One Networks – Investment Summary Document
Investment Type: Inter-Area Network Transfer Capability
Reference # Investment Name Gross Cost In-Service Date
D6 Installation of Static Var Compensator at Lakehead TS $22.5M Late 2010 Please see Exhibit D1, Tab 3, Schedule 3, Table 2 for cash flow and other details about each project. Need:
To replace the Lakehead TS synchronous condenser that failed in 2005 with a static var compensator (“SVC”). This replacement is required in order to mitigate concerns about power quality and risk of voltage instability. Not proceeding with this investment would result in sub-standard voltage support in the West System (northwestern Ontario).
Summary:
The 230kV transmission system between the Manitoba border and Wawa area is the backbone of the bulk power system in the West System. It allows incorporation of the local generation, import from and export to Manitoba and Minnesota, the transfer of surplus West System generation to the rest of Ontario during the peak load periods, and the transfer of generation from the East System during the off-peak periods when the output of the local generation is not sufficient to meet West System load requirements. There have always been significant challenges in dispatching of reactive power devices in the area to maintain acceptable voltages, security, and reliability of the system in West System due long transmission circuits and the daily variation in power transfers across this system. Until 2005, there were two synchronous condensers at Lakehead TS to facilitate the voltage control in the area. The older of the two, Unit C7 (+48/-24MVar) that was placed in-service in 1955, suffered a major failure in December 2005. Following a detailed analysis, it has been determined that this unit is not repairable, primarily because of lack of spare parts. The companion Unit C8, in-service since 1969, is now the only continuous voltage control device for maintaining the bulk system voltage in the area. Although it is feasible to control the voltage with only Unit C8, it would be difficult to maintain the system voltage if that unit was forced out-of-service. Furthermore, experience has shown that the West System can experience huge voltage excursions (i.e. voltage has risen to as high as 280kV). In such cases it has been difficult to bring down the voltage in a timely manner even with two synchronous condensers in-service. As a result, there is a significant and increasing risk of substandard operating voltage, poor power quality, and voltage instability in the West System if the failed condenser Unit C7 were not replaced.
The IESO System Impact Assessment Report (CAA ID 2006-247) indicates the installation of a +60/-40MVar SVC at Lakehead is required to meet the need of providing dynamic voltage control to enable power transfer capability in the West System. This project was identified in the IESO’s December 2007 Ontario Reliability Outlook.
Results:
Provide necessary reactive reserve margin, effectively maintain acceptable voltage, and eliminate operational concerns.
Project Classification per OEB Filing Guidelines / IPSP Status: Project Class: Development
Project Need: Non-Discretionary: The project is required to replace the failed synchronous condenser to address voltage stability and operational concerns.
Hydro One Networks – Investment Summary Document
Investment Type: Inter-Area Network Transfer Capability
Reference # Investment Name Gross Cost In-Service Date
D7 Northeast Transmission Reinforcement: Installation of Static Var Compensators at Porcupine TS and Kirkland Lake TS
$108.6M Late 2010
D8 Installation of Series Capacitors at Nobel SS $47.2M Late 2010 Please see Exhibit D1, Tab 3, Schedule 3, Table 2 for cash flow and other details about each project. Need:
To relieve congestion on the North-South (“N-S”) Interface in order to access available northern generation, and to enable incorporation of additional committed and planned renewable generation in northern Ontario in accordance with Ontario Power Authority (“OPA”) recommendation and the Government directives. These projects will also ensure that the transfer of power from committed and planned generation will not have adverse impact on the supply reliability to electricity consumers in northeastern Ontario. Not proceeding with these investments would result in bottling of economic generation in northern Ontario and utilization of uneconomic generation in the south during peak loading conditions.
Summary:
The existing north and south electricity systems in Ontario are interconnected by two 278km long 500kV single- circuit lines between Hanmer TS and Essa TS and one 91km long 230kV single-circuit line between Otto Holden TS and Des Joachims TS. These circuits comprise the N-S Interface, which allows transfer of generation that is surplus to northern Ontario into southern Ontario during critical peak load conditions.
Currently, the N-S Interface has a transfer capability of 1,300MW without Generation Rejection (“GR”) or 1,400 MW with GR based on voltage and transient stability considerations. With the recent addition of new generation and the reduction of load in northern Ontario, the transfer capability limitations on the N-S Interfaces have resulted in constraining up to 400MW of economic generation, mostly during the critical peak load conditions. The congestion across the N-S interface is expected to increase further over the next few years as over 500MW committed and planned generation will be placed in-service in the north.
In order to mitigate concerns about increasing congestion on the N-S Interface and to enable renewable generation in the north as per the Government’s direction, the OPA has recommended near term measures to enhance the N-S