N-1December 3, 2025 - Storm Outage Analysis Report
29 passages
1 1 1 1 1 1 // \ 5 CB West 12/3/2025 8:02 Grand Étang 50 30 76 1 Tree Contacts Falling Trees High winds and heavy snow caused trees to contact the lines. 165 28.83 CB East 12/3/2025 17:43 Sydney 340 44 87 2 Failed/ Damaged Equipment Electr...
AI summary The document details multiple power outages in Nova Scotia caused by severe weather conditions, including high winds, heavy snow, and heavy rain. These outages were due to falling trees and equipment failure, impacting thousands of customers across different regions.
SECTION 4: ZONE SUMMARY IMPACT SUMMARY – VALLEY Cause of Outages (CHI) Heavy, wet snow accumulated on trees and power lines throughout the region. The majority of interruptions were caused by tree contacts, as the weight of the snow bent o...
AI summary Heavy, wet snow caused power outages in the Valley region, primarily due to tree contacts resulting from the weight of the snow bending or breaking branches and pushing them into power lines.
Outage Summary: Customers Impacted: 18,029 Customer hours of interruption: 114,241 Full Restoration\ : 38.50 Hours
AI summary An outage impacted 18,029 customers, resulting in 114,241 customer hours of interruption. Full restoration was achieved after 38.50 hours, highlighting the scale and duration of the service disruption.
Customers Restored within X hours of Storm Onset Valley % Within 6 Hrs 19.40% Within 12 Hrs 77.38% Within 24 Hrs 95.56% Within 48 Hrs 100.00% This table represents the percentage of customers restored within 6, 12, 24, or 48 hours of the s...
AI summary The table shows the percentage of customers in Valley restored within specific timeframes after a storm, with 95.56% restored within 24 hours and 100% within 48 hours. The average restoration time was 14.47 hours.
SECTION 4: ZONE IMPACT SUMMARY – VALLEY TOP TWO EVENTS BY DURATION & CUSTOMER IMPACT
AI summary Section 4 presents a summary of zone impacts for the Valley, focusing on the top two events by duration and customer impact. The analysis highlights outage causes (CHI) and their effects on service reliability and customer experience, though specific details of events are not provided in the excerpt.
Duration Zone Date/ Time Weather Station Direction (Degrees) Max Wind Gusts (km/h) Temp (°C) Cause Sub-Cause Description Customer s Impacted Duration (Hours) Valley 12/3/2 025 7:00 Greenwood 10 20 35 1 Tree Contacts Falling Trees Heavy sno...
AI summary The tables list outages in the Valley zone caused by falling trees due to heavy snow, impacting 1 to 1596 customers with durations from 1.6 to 35.67 hours.
\ elapsed time from first outage event to restoration of last event Customers Restored within X hours of Storm Onset South Shore % Within 6 Hrs 63.34% Within 12 Hrs 98.10% Within 24 Hrs 99.98% Within 48 Hrs 100.00% This table represents th...
AI summary The table shows the percentage of customers in the South Shore region who were restored within specific timeframes after the storm, with 63.34% restored within 6 hours and 100% within 48 hours. The average restoration time for the region was 4.39 hours.
SECTION 4: ZONE IMPACT SUMMARY – SOUTH SHORE TOP TWO EVENTS BY DURATION & CUSTOMER IMPACT
AI summary This section outlines the top two events by duration and customer impact for the South Shore zone, though no specific details are provided in the given text.
SECTION 4: ZONE IMPACT SUMMARY – NORTHERN Heavy, wet snow accumulated on trees and power lines throughout the region. The majority of interruptions were caused by tree contacts, as the weight of the snow bent or broke branches and pushed t...
AI summary Heavy, wet snow caused widespread power interruptions in the Northern zone, primarily due to tree contacts. The snow's weight bent or broke branches, leading to branches falling onto power lines and disrupting service.
Outage Summary: Customers Impacted: 6,889 Customer hours of interruption: 33,164 Full Restoration\ : 31.03 Hours
AI summary An outage impacted 6,889 customers, resulting in 33,164 customer-hours of interruption. Full restoration was achieved after 31.03 hours, highlighting the scale and duration of the service disruption.
SECTION 4: ZONE IMPACT SUMMARY – NORTHERN TOP TWO EVENTS BY DURATION & CUSTOMER IMPACT
AI summary Section 4 summarizes the top two events in the Northern Zone by duration and customer impact, focusing on outage causes and their effects. The analysis highlights key factors influencing service disruptions and customer experience in the region.
SECTION 4: ZONE IMPACT SUMMARY – NORTHEAST Cause of Outages (CHI) Some high winds along with wet snow led to some outages in the region. The majority (81%) of customer hours of interruption were from one event where the heavy wet snow on t...
AI summary The Northeast zone experienced outages primarily caused by heavy wet snow on trees leading to tree-line contact. 81% of customer interruption hours resulted from a single event involving this cause, with high winds and wet snow contributing to the outage conditions.
Outage Summary: Customers Impacted: 3,500 Customer hours of interruption: 6,364 Full Restoration\ : 21.58 Hours
AI summary An outage affected 3,500 customers, resulting in 6,364 customer hours of interruption. Full restoration was achieved after 21.58 hours, highlighting the duration of service disruption and recovery efforts.
SECTION 4: ZONE IMPACT SUMMARY – METRO TOP TWO EVENTS BY DURATION & CUSTOMER IMPACT
AI summary Section 4 presents a summary of the top two events in Metro by duration and customer impact, focusing on zone-level outage data. The section likely analyzes outage causes (CHI) and their effects on service reliability and customer experience.
SECTION 4: ZONE SUMMARY IMPACT SUMMARY – EASTERN SHORE Cause of Outages (CHI) This region was not impacted the by weather and had just one event during the weather event.
AI summary The Eastern Shore region experienced no weather-related impacts, with only one outage event recorded during a weather event. This suggests minimal disruption to the area's energy infrastructure from climatic factors.
Outage Summary: Customers Impacted: 1 Customer hours of interruption: 4 Full Restoration\ : 4.44 Hours
AI summary A single customer experienced a 4-hour outage with full restoration achieved after 4.44 hours. The summary highlights minimal customer impact and restoration timeline, though no specific cause or broader implications are detailed.
Outage Summary: Customers Impacted: 3,151 Customer hours of interruption: 19,032 Full Restoration\ : 33.26 Hours
AI summary The outage affected 3,151 customers, resulting in 19,032 customer hours of interruption. Full restoration was achieved after 33.26 hours, highlighting the duration of service disruption and the scale of impact on customers.
Adverse Weather Cause of Outage (CHI) \ elapsed time from first outage event to restoration of last event
AI summary The document includes figures and images related to adverse weather as a cause of outages (CHI), specifically referencing elapsed time from the first outage event to the restoration of the last event. No textual analysis is provided in the chunk.
Duration Zone Date/ Time Weather Station Direction (Degrees) Max Wind Gusts (km/h) Temp (°C) Cause Sub-Cause Description Customer s Impacted Duration (Hours) Cape Breton West 12/3/2 025 8:02 Grand Étang 50 30 54 1 Tree Contacts Falling Tre...
AI summary The document details outage events in the Cape Breton West zone, caused by high winds, heavy snow, and falling trees, impacting a total of 1,511 customers with durations ranging from 2.19 to 28.83 hours.
Outage Summary: Customers Impacted: 5,342 Customer hours of interruption: 18,840 Full Restoration\ : 35.10 Hours
AI summary An outage impacted 5,342 customers, resulting in 18,840 customer hours of interruption. Full restoration was achieved after 35.10 hours.
SECTION 4: ZONE IMPACT SUMMARY – CAPE BRETON EAST TOP TWO EVENTS BY DURATION & CUSTOMER IMPACT
AI summary Section 4 summarizes the top two outage events in Cape Breton East by duration and customer impact, focusing on the causes (CHI) and their effects on service reliability and consumer experience.
CEA DEFINITIONS CI = Customer Interruptions Total number of customers without power CHI = Customer Hours of Interruption Combination of customers and duration SAIFI = Average Outage Frequency Customer interruptions / # of customers SAIDI =...
AI summary Defines key metrics (CI, CHI, SAIFI, SAIDI, CAIDI) used to measure power outage frequency, duration, and impact, providing formulas for calculation.
Loss of supply Interruptions due to problem in the bulk electricity system (transmission)
AI summary The document discusses interruptions in electricity supply caused by problems in the bulk electricity system, specifically within the transmission network. This falls under the broader theme of system reliability and grid performance.
Tree contacts Interruptions caused by trees or tree limbs contacting energized circuits
AI summary The document addresses power interruptions caused by trees or tree limbs contacting energized circuits, highlighting a key reliability concern for the electricity grid. This issue impacts service continuity and may be a focus for infrastructure planning and reliability measures.
Lightning Interruptions due to lightning strike on energized circuits
AI summary The document addresses power interruptions caused by lightning strikes on energized circuits, highlighting their impact on system reliability and customer service. This is a key consideration in grid management and outage analysis.
Defective equipment Interruptions resulting from equipment failures
AI summary The section addresses interruptions caused by equipment failures, likely examining their impact on system reliability and outage metrics such as customer interruptions and average outage durations.
Adverse weather Interruptions resulting from weather conditions (e.g. Rain, ice storms, snow, winds, extreme ambient temperatures, freezing fog, or frost)
AI summary The document discusses service interruptions caused by adverse weather conditions such as rain, ice storms, snow, wind, extreme temperatures, freezing fog, and frost. These factors contribute to power outages and impact system reliability.
Adverse environment Interruptions due to equipment being subjected to abnormal environmental conditions (e.g. Salt spray, contamination, humidity, corrosion, vibration, fire, or flooding)
AI summary The text discusses interruptions caused by equipment exposure to adverse environmental conditions such as salt spray, contamination, humidity, corrosion, vibration, fire, and flooding. These factors contribute to service disruptions and reliability challenges in the energy sector.
Foreign interference Interruptions due to external contacts beyond the control of the utility (e.g. Birds, animals, vehicles, dig -ins, or other foreign objects)
AI summary The document identifies interruptions caused by external factors such as birds, animals, vehicles, dig-ins, and other foreign objects, which are beyond the utility's control. These factors contribute to service disruptions, highlighting challenges in maintaining system reliability.
101379NSEB (NSPI) IR-1 to IR-9
5 passages
Request IR-1: - For this outage report, using December 3, 2025, 00:00 to December 3, 2025, 20:00 as the - time axis, please provide the following for each of the eight regions mentioned on PDF page 4 - a) A plot of hourly wind speed foreca...
AI summary Request IR-1 seeks data on an outage report for December 3, 2025, requiring hourly plots comparing forecasted and actual wind speed, gusts, precipitation, and temperature across eight regions. The request emphasizes detailed regional analysis for each weather parameter.
Request IR-4: - Please provide a detailed explanation for why the Valley region experienced significantly higher - Customer Hours of Interruption (CHI) relative to other regions during this event. In your response, - please address the fol...
AI summary Request IR-4 seeks an explanation for the Valley region's higher Customer Hours of Interruption (CHI) during an event, focusing on vegetation management practices, risk alignment, crew deployment, and restoration performance compared to other regions.
Request IR-6: - Please provide a system wide assessment of distribution automation and circuit segmentation. - The response should include: - a) The percentage of feeders equipped with automated sectionalizing capability; and - b) A compar...
AI summary Request IR-6 seeks a system-wide assessment of distribution automation and circuit segmentation, focusing on the percentage of feeders with automated sectionalizing capability and a comparison of restoration times between automated and non-automated circuits.
Request IR-7: - Please provide a detailed breakdown of outages attributable to equipment failure. The response should include: - a) Failure rates by asset class; - b) The age profile of failed assets at the time of failure; and - c) The pr...
AI summary Request IR-7 seeks a detailed analysis of outages caused by equipment failure, requiring failure rates by asset class, age profiles of failed assets, and preventative maintenance records for affected components. The request focuses on system reliability and asset management practices.
Request IR-8: - Please provide an evaluation of restoration prioritization practices, including an assessment of - the impacts of the "largest first" restoration approach. The response should address: - a) The comparative impact on rural v...
AI summary The document requests evaluations of restoration prioritization practices, focusing on the 'largest first' approach's impact on rural/urban customers and outage duration, and field resource utilization during events, including crew deployment, response times, and productivity metrics.