g3 Alternative Gas Solutions Todd Irwin GE Grid Solutions November 15, 2018

Agenda What is g3? Why g3? Availability Next Steps FAQ

What is g3? CO2 Novec 4710 gas O2

Why g3? GE Selection Criteria Many Candidates, Minimal Success SELECTIVE Many Candidates, Minimal Success N2 CO2 Dry Air Low dielectric strength Fluro-ketones High boiling point Vacuum Voltage limitations CF3I Toxicity Perfluoro-carbons High global warming potential High dielectric strength No voltage limitation Low liquefaction temperature Low global warming potential Qualified non-toxic like SF6

Why g3? Reduces gas Global Warming Potential by >99%

Why g3? Low global warming potential: >99 % reduction versus SF6 Dielectric performance: 100 % of SF6 with adequate Novec 4710 ratio and pressure Application: -25/-30 oC and all voltage levels No voltage or current limitation Similar handling procedures Toxicity: Same toxicity class as SF6 (new and polluted gas) Material compatibility: compatible with the standard materials used in HV equipment Chemically stable : no degradation up to 700 oC EU Reach registration : done Same dimensions and footprint as for SF6 products Technical performance similar to today’s SF6 products g3 equipment price compatible to SF6

Why g3?

First Applications of g3 GE AIS Current Transformers 245 kV (-30°C) First Application: (Germany) -99.2% CO2 equivalent reduction GE Gas-Insulated Lines 420 kV (-25°C) First Application: (UK) -99.3% CO2 equivalent reduction Second Application: (Scotland) GE GIS 145 kV incl. CB (-25°C) First Application: (CH) -99.1% CO2 equivalent reduction Second Application: (FR) 1st Units Energized 2017 1st Units Energized 2017 1st Units Energized 2017

420kV GIB with g3 Total mass SF6 replaced = 1,360 kg (31,960 t CO2 eq.) Total mass of g3 installation = 625 kg (204 t CO2 eq.) Reduce CO2 emissions over 40 year life by 6,351 tonnes Energized in August 2018 g3 compartments differently identified to avoid incorrect filling Special gas analyzers and detectors used for g3 gas Similar handling procedures and maintenance to SF6

11 Industry Adoption g3 Gas–Insulated Lines 420 kV, -25 °C Denmark England Switzerland France South Korea Germany Scotland Netherlands g3 Gas–Insulated Lines 420 kV, -25 °C 3 sites – 483 meters g3 Gas–Insulated Substations 145 kV, -25 °C 8 sites – 51 bays LEADING UTILITIES Have decided to install equipment with g3 11 g3 AIS – Current Transformers 245 kV, -30 °C 2 sites – 6 CTs

Gas handling in factory Operation & maintenance g³ – Gas Management Gas supply Gas handling in factory End of life Operation & maintenance Gas handling on site

g3 – Gas Handling Tools Gas carts for gas filling, recovery and topping-up Gas quality check (humidity, ratio) Gas leakage detection PPE Complete set of tools developed to handle and check the gas safely and efficiently

g3 – Gas handling on site Liquid to gas filling Indoor application Use of DILO gas cart 110 kV GIS in Switzerland Small volumes of gas Gas to gas filling 245 kV CTs in Germany Liquide to gas filling Outdoor application Use of Air Liquide gas cart 420 kV GIL in England Liquide to gas filling Outdoor application Use of Air Liquide gas cart 420 kV GIL in Scotland Successful gas handling performed on the first 4 projects with g³

Next steps – g3 – Where do we go? GIL up to 420 kV Products Installed or under installation Policies Experience HV Instrument Transformers up to 245kV 145 kV GIS Design for g3 Full HV equipment Product Range New GIS/AIS designed for g3. Availability Demand. 72,5 kV GIS 145 kV Live Tank 145 kV Dead Tank

FAQ – g3 Q: Can I use g3 in my SF6 GIE? A: No. It is not a 1:1 replacement. Q: What are the differences between SF6 and g3 GIE? A: Some differences include: Operating Pressure, Density Monitor, Interrupter Components, Gaskets. Q: Isn’t it complicated to handle gas mixtures like g3? A: No. While mixing equipment is available, g3 is available pre-mixed. Q: What special handling is required for gas mixtures like g3? A: g3 handling will be comparable to SF6 with similar equipment and procedures. Q: Why doesn’t the industry have a standard SF6 alternative? A: Manufacturers are working with users to identify the best solution.

FAQ – g3 Q: Is g3 safe? A: Safety precautions for g3 are similar to SF6.

FAQ – g3 Q: How do I evaluate the environmental benefit of g3 ? A: Use the CO2 Equivalent Calculator. https://www.gegridsolutions.com/productexplorers/greengas/default.aspx#/?utm_source=gswebsite&utm_medium=resources&utm_campaign=g3-explorer#/

FAQ – g3 Q: How long will SF6 equipment be available? A: GE continues to invest in SF6 equipment with new designs and testing methods

Questions?