Best Practices for SF6 Leak Reduction At Consolidated Edison Co. Of NY Patrick Di Lillo Technical Specialist

Agenda Con Edison Overview SF6 Background Information Current/Emerging Regulation USEPA Partnership SF6 Emissions at Con Edison Addressing the Leaks Moving Forward

Con Edison

Con Edison Electrical System Overview Con Edison of New York Con Edison Electrical System Overview 3.2 million electric customers 660 square miles 13,322 MW peak load 94,000 miles of underground cable 36,000 miles of overhead cable 101 Substations 39 transmission 62 distribution ~210,000 lbs. of SF6

SF6 Background Information Effective insulating and arc-extinguishing medium Highly efficient in transmission and distribution equipment and switchgear Chemically inert, high thermal stability, non-flammable/ non-toxic Allows for small station footprint in urban area SF6 is a greenhouse gas with a global warming potential (GWP) 22,800 times that of carbon dioxide (CO2) Extremely long atmospheric lifetime of up to 3,200 years Currently no viable alternative to SF6 Kapiteleinführung

Current/Emerging Regulation No US EPA or NYSDEC mandated SF6 reduction regulation in effect Both the California Air Resources Board (CARB) and Massachusetts Department of Environmental Protection (MassDEP) have already instituted regulatory constraints for SF6 reduction Kapiteleinführung

USEPA SF6 Emission Reduction Partnership for Electric Power Systems Since 1999, members of the U.S. electric power industry and the US EPA have been voluntarily working together to reduce SF6 emissions and share information 90% decrease in SF6 emissions since 1999 95% decrease in emissions rate since inception Since 2011, we have additionally been mandated to report all of our Greenhouse Gas Emissions (including SF6) through the US EPA Greenhouse Gas Reporting Program (GHGRP).

Con Edison Historical SF6 Emissions (lbs.)

Con Edison Historical SF6 Emission Rate 6.03%

7.5% emissions rate of Nameplate Capacity SF6 Emissions 2014-2016 7.5% emissions rate of Nameplate Capacity

Addressing the Leaks Established the Fix-It-Now (FIN) Team Cross-Organizational Effort Substation Operations, Engineering, System Operations & EH&S Improve the Timeliness & Effectiveness of SF6 Repairs Prioritize & develop a plan of action for top leakers Focused systematic approach to repairs Identify Leak – Plan Work – Repair – Test – Document Ensure quality of work and documentation Establish method for forecasting gas calls Centrally Institute Best Practices Repair tools, practices and ePLAN Templates Procedures and training SF6 inventory control and tracking

 Addressing the Leaks Minimize Number of Samples ZERO Purge SF6 Analysis Previously emitted 2 lbs per sample 500-700 lbs released per year New DILO SF6 gas analyzers Improved Tool for Leak Detection State of the Art FLIR GF306 SF6 Camera 

Addressing the Leaks Heighten Sensitivity Associated with SF6 Leaks VP Communication Transparent Maximo Reports Closely monitor reported SF6 fills through daily gas call reports Aid in monitoring the quality of data entered

Moving Forward Nameplate Capacity Accuracy Corrected Nameplate Capacity New Requirements for Nameplate Capacity Continue Temporary Leak Repair Composite wrap Colt Clamps Permanent Repairs Eliminate centralized gas fill system Remove clamps on leaking welds and re-weld/repair (outage required) NDE testing on patches/welds that aren’t clamped to identify possible future leak areas Replace temporary bypass piping clamps with stainless tubing and DILO self-sealing fittings

Moving Forward Continue to Leverage Capital Programs SF6 Peer Team Circuit Breaker Reliability Program SF6 GIS Bus Overhauls Automatic Ground Switch Retirements GIS Replacements SF6 Peer Team SSO/EH&S-Air/Chem Lab/Engineering/TLC Monthly meetings to keep lines of communication open Maintain focus, identify and work through issues together Implement New Technology with R&D GIS phase-isolated continuous pressure monitoring GIS bus epoxy coating Heat shrink wrap technology(EPRI researching application)

Moving Forward Refine SF6 Gas Procedures and Practices Guidance presently being provided through Engineering Test Letters Document best practices in Smart Procedures, ePLAN Templates, Standard Maximo Job Plans Improve block training, supervisor training and refresher training

Questions? Patrick Di Lillo Technical Specialist Consolidated Edison Co. Of NY