2021 Investor Day Presentation

Living in uncertain times: renewable energy & dry year flexibility Hydro inflow deficits of 5TWh (20%) have historically been managed by maintaining thermal capacity, flexible thermal fuel storage, and flexible thermal fuel deliveries Newly committed wind and geothermal projects (2.7TWh) will move the system to 90% renewable over the next few years The Government has stated its intent for a 100% renewable system by 2030 They are proposing the Onslow-Manorburn pump storage scheme as a key plank towards this goal As more wind enters the system, it too can face extreme deficits of 8-10%. Solar also faces deficits of up to 3-5% A Tiwai smelter closure by the end of 2024 could see 5TWh of excess Southland-Otago generation attempting to flow northward In response to this regional energy imbalance, large-scale demand. stimulation projects are being pursued Significant new demand in Southland that is also flexible could address regional energy balance and create an alternative mechanism for dry-years. Major Generation Sources Scaled to size of mean energy contribution: 2021-23 Hydro storage Thermal storage Hydro generation Coal generation Gas generation Geothermal generation Wind generation Major load centre Net transfer to NI - HVDC link Meridian. Source: Meridian 11 MAY 2021 2021 INVESTOR DAY PRESENTATION 26

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