Topic:"Distribution Planning" in M12728

SECTION 4: PROVINCIAL IMPACT SUMMARY – DECEMBER 19-20, 2025 CB West CB East This map presents a geospatial view of the overall impact to the province by customer hours of impact (CHI). This map is a symbolized view of impacted areas by 8 g...

AI summary A severe weather event on December 19-20, 2025, caused power outages in Nova Scotia due to wind, snow, and rain. Over 600 field resources were deployed to restore power, and a map illustrates the impact by customer hours of impact across eight geographical zones.

SECTION 4: PROVINCIAL HIGHLIGHTS Zone Date/ Time Weather Station Direction (Degrees) Wind (km/h) Max Wind Gusts (km/h) Temp (°C) Cause Sub-Cause Description Customers Impacted Duration (Hours) Valley 12/19/2025 23:03 Greenwood l 210 28 96...

AI summary This section presents a table detailing weather-related power outages in Nova Scotia on December 19-20, 2025. Each entry includes the zone, time, weather conditions, cause of the outage, number of customers impacted, and duration of the outage. The primary causes were high winds, heavy rain, and falling trees, leading to recloser operations and broken leads on transmission lines.

Customers Restored within X hours of Storm Onset South Shore % Within 6 Hrs 3.66% Within 12 Hrs 17.17% Within 24 Hrs 70.01% Within 48 Hrs 96.35% This table represents the percentage of customers restored within 6, 12, 24, or 48 hours of th...

AI summary The table shows the percentage of customers in the South Shore region restored within various timeframes after a storm, with 96.35% restored within 48 hours. The average restoration time for the region was 23.1 hours.

Adverse Weather Cause of Outage (CHI) \ elapsed time from first outage event to restoration of last event

AI summary The text discusses adverse weather as a cause of outages, referencing figures and images that illustrate the impact of weather-related events on power systems. It includes a note on elapsed time from the first outage event to the restoration of the last event.

Event December 19- 20 2025 January 4-5 2018 Customers Interrupted 268,354 412,793 Customer Hours of Interruption 2,112,088 2,094,094 Customers Restored in 48hrs 98.93 99.88 Field Resources Available >600 >440 Peak Winds 115 km/h 150 km/h

AI summary The table compares outage data from two events: December 19-20, 2025, and January 4-5, 2018. It shows the number of customers interrupted, customer hours of interruption, restoration rates, field resources available, and peak wind speeds during each event.

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 = Average Outage...

AI summary The text defines key metrics used to measure power interruptions, including the total number of customers without power, customer hours of interruption, average outage frequency, average outage duration, and average outage duration for those interrupted.

Storm Outage Analysis Report December 19-20 NSEB IR-3 Attachment 1 Page 5 of 5 Classification rural rural rural rural rural rural rural rural rural suburban suburban rural rural FEEDER CLASSIFICATION TRIMYEAR AVGVEGCONDITION 100C-421 rural...

AI summary The document presents a table detailing various feeders, their classifications (rural, suburban, urban), trim years, and average vegetation condition scores. This data is part of a storm outage analysis report for December 19-20, focusing on infrastructure and vegetation management.

NON-CONFIDENTIAL 1 (d) NS Power does not re‑evaluate all equipment failures associated with weather‑related 2025-12-20 81S-306 94.9 1.6 1 1.581333333 Defective Equipment Mechanical Failure Event Day Jumper 2025-12-19 101H-423 119.9 2.0 14...

AI summary The document provides details on equipment failures, including dates, matter numbers, and associated metrics such as customer interruptions and outage durations. NS Power is noted for not re-evaluating all equipment failures linked to weather-related events.

17 Region Unknown / Scheduled Loss of Tree Failed Adverse Adverse Foreign Other Outage Supply Contacts Equipment Weather Environment Interference Valley 2 2 - 115 4 140 - - South Shore 9 3 - 116 - 139 1 - Northern - - 6 28 1 64 - - Northea...

AI summary The text presents a table detailing outage data across various regions in Nova Scotia, including categories such as tree contacts, failed equipment, and adverse weather. It also includes a request for specific outage metrics categorized by event types, such as transmission-supplied events and customer-specific outages.

1 (b) The table below shows the minimum temperature recorded during the weather event. Weather Zone Minimum Temperature During Weather Event (°C) Valley -11 South Shore -7 Northern -12 Northeast -10 Metro -10 Eastern Shore -7 CB West -8 CB...

AI summary The text provides two tables showing the minimum temperatures recorded during a weather event and the average duration of power outages after temperatures fell below freezing in various weather zones across Nova Scotia.

NSEB, large weather events are inherently unique, and differences in timing, damage NON-CONFIDENTIAL 23 outage and damage to the system using the experience and outage data obtained from 24 previous storm events. 25 26 (c) The model is use...

AI summary The Nova Scotia Electric Board (NSEB) acknowledges that large weather events are unique and uses historical outage and damage data from previous storm events to model the impact of future adverse weather events on customer outages and system damage.