Quarterly Operational Update

QUARTERLY OPERATIONAL UPDATE
Three months ended 31 December 2025
MERCURY NZ LIMITED QUARTERLY OPERATIONAL UPDATE01
>> QUARTERLY HIGHLIGHTS
HIGH
NATIONAL
HYDRO
INFLOWS
TAUPO
STORAGE
REMAINS
ELEVATED
NEW OEC5
GEOTHERMAL
GENERATION
>> COMMENTARY
Market summary
Highnationalhydrologicalinflowsof 98
th
percentile wasreflected in lower wholesale spotelectricity prices
averaging$40/MWh in Auckland for the quarter.Forward prices in Auckland for FY26 have eased
considerably to $135/MWh due to high inflows and above average hydro storage levels.
National demand was up 3.1% for the quarter relative to PCP, primarily due to New Zealand Aluminium
Smelter resuming normal operations after a period of demand response curtailments.
Portfolio management has provided astrong Q3storedhydrostarting position
Waikato catchment hydrological inflows were 88
th
percentilefor the quarter, and this resulted in higher hydro
generation of 1,072 GWh, up 200 GWh (23%) relative to PCP.Hydro spill was significant at ~345 GWh for the
quarter, to maintain lakes within high operating levels. Taupō hydro storage ended the quarterwith anabove
averagelake level.
Wind generationwas32 GWh(6%)higherfor the quarterrelativeto PCP.Geothermal generation was 50 GWh
(9%) lower than PCP (539 GWh compared to 589 GWh) primarily driven by planned maintenance outage at
Ngā AwaPūrua which coincided with low spot prices and was delivered on budget and on time. Commercial &
Industrial yield (physical & end-user CfDs) was lower by $3.2/MWh for the quarterrelativeto PCP. Physical
C&I yields were lower as some contracts repriced to a lower 2026 electricity forward curve, while End-User
CfDs were lower due to new long-term agreements.
Our differentiated bundling and value-creation strategy lifted the share of customers with two or more
products by 10% to 223k connections with telcoand mobile connections increasing by 30k relativeto PCP.
We will deliver more reliable and renewable energy with Ngā Tamariki OEC5 close to completion
Ngā Tamariki OEC5 geothermal expansion is close to completion.Commissioning of the new OEC5 unit
started in January and once completed, it will increase site generation by 390 GWh per annum and net
output by 46 MW. Full commissioning is expected by the end of Q3.
RESULTED IN LOW WHOLESALE
ELECTRICITY SPOT PRICES
PROVIDINGA STRONG
Q3PORTFOLIOPOSITION
COMMISSIONING STARTED AS
PLANNED WITH POTENTIAL
GENERATION UPSIDE RELATIVE
TO GUIDANCE

584582
1
109107
186169
4330
223203
VWAP
3
VolumeVWAP
3
VolumeVWAP
3
VolumeVWAP
3
Volume
(GWh)(GWh)(GWh)(GWh)
1,4631,4733,3613,324
4
9169702,2652,294
5
5475031,0961,030
8184192193
6
1,5441,5573,5533,517
7507501,5691,621
292244690601
7
4585068801,020
545011581
1
4444751,2381,339
1
4444801,2381,355
2
2
2,1781,9964,7294,194
1,0728722,4611,836
8
5395891,2301,272
152196296398
415339742685
5325931,2001,458
7
5325931,2001,458
9
2-5765-172
1
2
3
4
5
6
7
8
9
MERCURY NZ LIMITED QUARTERLY OPERATIONAL UPDATE02
Electricity connections (ICPs)
Gas connections
OPERATING INFORMATION
Three months ended
31 December 2025
Three months ended
31 December 2024
Six months ended
31 December 2025
Six months ended
31 December 2024
CONNECTION NUMBERS ('000s)
Customers with 2 or more products
Telecommunication connections
Mobile connections
($/MWh)($/MWh)($/MWh)($/MWh)
ELECTRICITY SALES
Physical
166.05155.53170.32161.05
Mass Market
195.55174.30179.08168.16
Commercial & Industrial116.70119.38152.22145.19
Network Losses
Physical Purchases39.7145.0096.71201.35
Financial122.47136.65135.98151.72
End User CfDs125.10130.06130.43134.94
Other Sell CfDs120.79139.83140.34161.60
Spot Settlement of CfDs37.6242.3386.85179.33
Spot Customer Purchases41.1239.8992.60147.02
Gas Sales ($/GJ, TJ)42.3631.6138.1627.41
Gas Purchases ($/GJ,TJ)11.7012.9217.3623.06
Telco Sales ($/month/connection)76.3681.6576.5482.26
Telco Costs ($/month/connection)55.4056.5655.6456.77
ELECTRICITY GENERATION
Physical50.1150.8990.46165.46
Hydro54.3157.7399.75204.93
Geothermal (consolidated)30.6339.3281.74167.24
Wind Spot31.3426.8770.96133.12
Wind PPA72.5966.6081.9275.11
Spot Settlement of CfDs37.2339.9690.40203.14
Net Position
Financial110.91106.88119.93122.02
Buy CfDs110.91106.88119.93122.02
Includes Virtual Asset Swap volumes of 76 GWh for the 3 months ended 30 June 2025 and 113 GWh for the 3 months ended 30 June 2024 and of 151
GWh for the 12 months ended 30 June 2025 and 226 GWh for the 12 months ended 30 June 2024. Also includes the Manawa CFD volumes relating to
the Trustpower retail transaction since May 2022
Includes Mercury’s 65% share of Nga Awa Purua generation
Includes all physical and financial buys and sells except spot customer purchases and wind ppa
Includes LPG bottle connections
Includes mobile
VWAP is volume weighted average energy-only price sold to customers after lines, metering and fees
Mass market includes residential segments and non time-of-use commercial customers
Fixed-price, variable-volume (FPVV) sales to time-of-use commercial customers
Excludes spot customer purchases
>> OPERATING STATISTICS

> ELECTRICITY GENERATION BY COMPANY FOR THE THREE MONTHS ENDED 31 DECEMBER
Source: Transpower SCADA
> SHARE OF ELECTRICITY SALES (GWh) FOR THE THREE MONTHS ENDED 31 DECEMBER (EXCLUDING CFDs)
Source: Mercury Purchases and Transpower SCADA
MERCURY NZ LIMITED QUARTERLY OPERATIONAL UPDATE03
22%
38%
20%
8%
12%
Financial Year Q2 2026
MERCURY
MERIDIAN ENERGY
CONTACT ENERGY
GENESIS ENERGY
OTHER
>> MARKET DATA
20%
35%
22%
10%
13%
Financial Year Q2 2025
16%
84%
Financial Year Q2 2026
Mercury
Other
17%
83%
Financial Year Q2 2025

> OTAHUHU WHOLESALE PRICE AND NATIONAL HYDRO STORAGE LEVELS
Source: NZX Hydro and NZEM Pricing Manager (NZX)
> TAUPO STORAGE
Source: NZX Hydro
MERCURY NZ LIMITED QUARTERLY OPERATIONAL UPDATE04
$0
$50
$100
$150
$200
$250
0
500
1000
1500
2000
2500
3000
3500
4000
4500
5000
JulAugSepOctNovDecJanFebMarAprMayJun
$/MWh
GWh
AVERAGE NATIONAL STORAGEFY2025 NATIONAL STORAGE
FY2026 NATIONAL STORAGEROLLING 12 MONTH AVERAGE OTA SPOT PRICE
AVERAGE MONTHLY OTA SPOT PRICE
0
100
200
300
400
500
600
JulAugSepOctNovDecJanFebMarAprMayJun
GWh
AVERAGE SINCE 1999FY2025FY2026

> OTAHUHU ASX FUTURES SETTLEMENT PRICE
Source: ASX
> BENMORE ASX FUTURES SETTLEMENT PRICE
Source: ASX
MERCURY NZ LIMITED QUARTERLY OPERATIONAL UPDATE05
$183.04
$178.18
$171.63
$173.76
$183.33
$171.36
$160.31
$187.10
$176.55
$134.99
$192.33
$183.50
$0
$50
$100
$150
$200
$250
202620272028
$/MWh
Financial Year
As at 31/12/2024As at 30/06/2025As at 30/09/2025As at 31/12/2025
$151.36
$143.76
$137.73
$148.63
$155.65
$147.48
$141.52
$164.76
$155.73
$117.93
$169.63
$160.40
$0
$20
$40
$60
$80
$100
$120
$140
$160
$180
202620272028
$/MWh
Financial Year
As at 31/12/2024As at 30/06/2025As at 30/09/2025As at 31/12/2025

> NATIONAL CONSUMPTION (NON-TEMPERATURE ADJUSTED)
Source: Transpower Information Exchange
> AUCKLAND CLIMATE SUMMARY ( ⁰C)
FINANCIAL YEAR
Q1Q2Q3Q4
202612.417.9--
202512.517.119.715.3
202412.216.819.614.3
202312.917.219.215.1
202212.217.820.815.1
202112.316.919.514.8
Historical Average (since 1999)1216.219.514.3
Source: Met Service
> MONTHLY TOTAL CONSUMER RETAIL SWITCHING (ICPs)
Source: Electricity Authority
MERCURY NZ LIMITED QUARTERLY OPERATIONAL UPDATE06
8,505
8,327
8,364
8,380
8,447
8,474
1,247
1,262
1,273
1,270
997
1,259
0
2,000
4,000
6,000
8,000
10,000
12,000
Q2 2021Q2 2022Q2 2023Q2 2024Q2 2025Q2 2026
GWh
National ConsumptionTiwai Point Aluminium Smelter Consumption
10%
15%
20%
25%
30%
0
10000
20000
30000
40000
50000
60000
70000
80000
90000
Jul-16
Jan-17
Jul-17
Jan-18
Jul-18
Jan-19
Jul-19
Jan-20
Jul-20Jan-21
Jul-21
Jan-22
Jul-22
Jan-23
Jul-23
Jan-24
Jul-24
Jan-25
Jul-25
% Churn
Monthly ICPs
NZ MARKET CHURN (LHS)ANNUAL NZ MARKET CHURN % (RHS)