Topic:"Grid Modernization" in M03347

5.3 Province's Wind Integration Study The 2008, Hatch Ltd. Wind Integration Study identified and assessed the effects of integrating large scale wind power generation into Nova Scotia's electric power system. This study confirmed that "mor...

AI summary The 2008 Hatch Ltd. Wind Integration Study highlighted the need for detailed impact studies on transmission upgrades and operational demands from wind power integration. NSPI now monitors variable energy sources like wind to improve forecasting and ensure system stability and availability.

7.1 System Description The existing transmission system has over 5,200 kilometres of transmission lines at voltages at the 69 kV, 138 kV, 230 kV and 345 kV levels. - The 345 kV transmission system is approximately 468 kilometres in length...

AI summary The document details Nova Scotia's transmission system, including 5,200 km of lines at various voltage levels (69 kV to 345 kV), their construction materials, and interconnections with New Brunswick, Quebec, and Maine via the NPCC power system.

1. 2010 - Work will begin on the construction of additional transmission to the Western Valley area. This will include the construction of a 138 kV circuit between Canaan Road and Tremont, a 138 kV termination at Canaan Road and the additi...

AI summary The 2010 document outlines transmission infrastructure upgrades, including new 138 kV circuits, transformer installations, and reliability improvements. Projects aim to prevent outages, replace aging equipment, and integrate renewable energy sources like wind farms. Key initiatives include insulator replacement, switchgear upgrades, and grid expansions to enhance system reliability and accommodate renewable generation.

2. 2011 - The insulator replacement program will continue with the reinsulation of three circuits due to cement growth issues. - The transmission reliability investment program will continue targeting transmission switches and circuit brea...

AI summary The 2011 document outlines ongoing infrastructure projects including insulator replacement, transmission reliability investments, and upgrades to 138 kV and 69 kV circuits. Key initiatives involve dual high-speed protection systems at 138 kV substations, Gas Insulated Switchgear replacement, and reconductoring to avoid overloads. A second 345 kV tie to New Brunswick is also planned.

7. 2018 - An existing 69-25 kV transformer at Milton will be changed out for a unit rated 15/20/25 MVA. - There is a possibility of an additional supply to the Halifax downtown area. This could take the form of a 138 kV underwater cable fr...

AI summary In 2018, plans included replacing a 69-25 kV transformer at Milton with a higher-capacity unit and exploring new power supply options for Halifax, such as a 138 kV underwater cable from Dartmouth to Water St. Further evaluation of the latter option was slated to begin soon.

SYSTEM DESIGN CRITERIA Nova Scotia Power's interconnected system is divided into several classifications, each of which is governed by different design criteria. These classifications are as follows: - 1. Primary Transmission - 2. Secondar...

AI summary Nova Scotia Power's system is categorized into five classifications (Primary Transmission, Secondary Transmission, etc.), each governed by specific design criteria combining protection performance, system dynamics, and steady-state requirements. Protection design assumes a single coincident protection element failure.

The Design Criteria7 are: - 1. From normal system conditions, the Interconnected Transmission System dynamic response shall be stable and positively-damped following a permanent three-phase fault on any one system element except a generato...

AI summary The design criteria outline stability requirements for the Interconnected Transmission System following faults, emphasizing positive damping, prevention of cascade tripping, adherence to thermal ratings, and voltage control within specified limits. Fault clearance timelines and system element protections are also specified.

The Design Criteria are : - 1. From normal system conditions, the Interconnected Transmission System dynamic response shall be stable and positively-damped following a permanent three-phase fault on any one system element except a generato...

AI summary The Design Criteria outline requirements for the Interconnected Transmission System's stability and response to faults, including preventing cascade tripping, maintaining thermal ratings, voltage limits, and ensuring fault clearance. Criteria address three-phase and line-to-ground faults, steady-state conditions, and voltage regulation post-contingency.

TRANSMISSION ADDITIONS FOR GENERATION DEVELOPMENT SCENARIOS Distributed large-scale renewable generation, large-scale imports and exports and new inprovince thermal generation all have a potential role in serving Nova Scotia's future elect...

AI summary Nova Scotia's transmission system may require reinforcement to accommodate future renewable generation, imports/exports, and in-province thermal generation. NSPI's preliminary scenarios highlight transmission constraints and potential investments, though the information remains conceptual. These scenarios aim to inform long-term expansion planning to enable higher renewable energy integration, which NSPI supports.

a) Mainland (Metro) wind generation (100MW-150MW) development scenario Establish a new 138kV substation in the Dartmouth area along with rebuilding/reconductoring two existing circuits and building a new 138 kV circuit between Fall River a...

AI summary The proposed 100MW-150MW Mainland wind generation scenario involves establishing a new 138kV substation in Dartmouth, rebuilding two existing circuits, and constructing a new 138kV circuit between Fall River and Sackville to support the development.

c) Mainland (Lower Annapolis Valley) wind generation (100-150MW) development scenario This scenario requires the completion of a 138kV line L-6617 from Tremont to Canaan Rd currently scheduled for construction along with a new ring bus con...

AI summary The scenario outlines infrastructure upgrades required for a 100-150MW wind generation project in Lower Annapolis Valley, including 138kV line construction, ring bus configurations, substation modifications, and voltage upratings to support the development and integrate with existing transmission networks.

d) Mainland (Upper Annapolis Valley) wind generation (100-150MW) development scenario An existing 69 kV circuit between Sissiboo and Tusket would be rebuilt to a higher capacity. Substation modifications would be required at Canaan Road an...

AI summary The scenario outlines infrastructure upgrades for a 100-150MW wind generation project in Upper Annapolis Valley, including rebuilding a 69kV circuit, substation modifications at Canaan Road and Milton, replacing autotransformers, and separating 230kV circuits near Bridgewater to accommodate increased capacity.

e) Mainland (Northern Nova Scotia) wind generation (100-150MW) development scenario Construct a new 138kV line from Onslow to Springhill and install a 100 MVAR static compensator on the Onslow 230 kV bus along with increasing reactive powe...

AI summary The proposed 100-150MW wind generation project in Northern Nova Scotia requires infrastructure upgrades: a new 138kV line from Onslow to Springhill, a 100 MVAR static compensator at Onslow, enhanced reactive power compensation at Brushy Hill, and uprating an existing 230kV circuit to 345kV for transmission between Onslow and Brushy Hill.

f) Cape Breton Wind generation (150MW -250MW) development scenario An existing 230 kV circuit would be uprated to 345 kV to provide a 345 kV transmission connection between Onslow and Brushy Hill and reactive power compensation would be in...

AI summary The Cape Breton Wind generation scenario outlines infrastructure upgrades including uprating a 230 kV circuit to 345 kV, establishing new 345 kV substations at Port Hastings and Spider Lake, constructing 345 kV transmission lines to Woodbine and Spider Lake, a new Canso crossing, and adding 100 MVAR reactive compensation in the Dartmouth area.

2) Port Hawkesbury 60MW Biomass- Cape Breton Strait Area Scenario An additional line crossing the Strait of Canso would be constructed to eliminate the double circuit contingency limit. A bus reconfiguration at NSPI's Onslow 345kV EHV subs...

AI summary The Port Hawkesbury 60MW Biomass project requires infrastructure upgrades including a new line across the Strait of Canso, bus reconfiguration at Onslow substation, 138kV line terminal upgrades at Trenton, and switched capacitors at Brushy Hill, all managed by NSPI.

a) To facilitate a large import or export via NB interconnect To enable import, a new 345 kV transmission circuit would be required between Onslow to the New Brunswick system. An existing 230 kV circuit would be uprated to 345 kV to provid...

AI summary The text outlines infrastructure upgrades required to enable large imports or exports via the NB interconnect, including new 345 kV transmission circuits, uprating existing lines, reactive compensation, and a ring bus. Joint planning studies with New Brunswick are needed to assess system upgrades for firm import/export capacity.

b) Newfoundland Submarine Cable Import (300MW) or Export development scenario A 300 MW DC to AC terminal would be required at Onslow or Brushy Hill along with a DC submarine cable from Newfoundland to Cape Breton along with overhead DC tra...

AI summary A 300 MW DC to AC terminal and submarine cable infrastructure from Newfoundland to Nova Scotia is proposed, requiring upgrades to 345 kV transmission lines and a new ring bus at Hopewell. Further study is needed for potential energy exports through Nova Scotia.

a) Eastern Shore/Point Tupper Natural Gas Generator Scenario Substation expansions would take place at Point Tupper and Port Hastings including the addition of a 345/230 kV transformer at Port Hastings. A 345/138 kV substation would be est...

AI summary The Eastern Shore/Point Tupper scenario outlines required substation expansions and new transmission circuits to support a natural gas generator. Key infrastructure includes a 345/230 kV transformer at Port Hastings, a 345/138 kV substation at Spider Lake, and new 230 kV and 345 kV circuits connecting Point Tupper, Port Hastings, and Spider Lake.

b) Metro Large Natural Gas Generator Scenario Development of a 138 kV substation at Spider Lake to terminate two existing Dartmouth 138 kV circuits along with increasing the conductor size on two existing Dartmouth circuits. A new 138 kV c...

AI summary The Metro Large Natural Gas Generator Scenario outlines infrastructure upgrades including a new 138 kV substation at Spider Lake, conductor size increases on Dartmouth circuits, new 138 kV circuits to Sackville, and a high-capacity line between Tufts Cove and Brushy Hill, alongside substation modifications at Tufts Cove and Brushy Hill.