Meridian Energy monthly operating report for August 2025

Release






Meridian Energy Limited (ARBN 151 800 396) A company incorporated in New Zealand
Level 2, 98 Customhouse Quay, Wellington 6011
meridianenergy.co.nz
Stock Exchange Listings NZX (MEL) ASX (MEZ)
Meridian Energy monthly operating report for August 2025

11 September 2025


Attached is Meridian Energy Limited's monthly operating report for the month of August 2025.
Key points this month include:
• In the month to 8 September 2025, national hydro storage decreased from 87% to 79% of
historical average.
• South Island storage decreased to 73% of average and North Island storage decreased to 98% of
average by 8 September 2025.
• Meridian’s August 2025 monthly total inflows were 73% of historical average.
• Waiau catchment inflows in August 2025 were 67% of historical average.
• Meridian’s Waitaki catchment water storage at the end of August 2025 was 65% of historical
average.
• Snow storage in Meridian’s Waitaki catchment was 78% of average in early September 2025.
• Water storage in Meridian’s Waiau catchment was 84% of average at the end of August 2025.
• August was a dry and cool month, with both rainfall and temperatures below average for most of
the country.
• National electricity demand in August 2025 was 5.9% higher than August 2024.
• New Zealand Aluminium Smelters (NZAS) average load during August 2025 was 565MW.
• Meridian’s retail sales volumes in August 2025 were 12.8% higher than August 2024.
• Compared to August 2024, segment sales in residential were 35.3% higher (including Flick
customers), small medium business 7.2% higher, large business 14.6% higher, agriculture 2.2%
higher and corporate 4.3% higher.
Weekly lake storage updates are available on Meridian’s website. See comparative lake levels at:
www.meridianenergy.co.nz/power-stations/lake-levels


ENDS

Authorised for release by:

Jason Woolley
General Counsel and Company Secretary
Meridian Energy Limited


For investor relations queries, please contact:
Owen Hackston
Investor Relations Manager
021 246 4772
For media queries, please contact:
Philip Clark
Head of Communications
0278 385 710

7 cm
August 2025
Monthly operating report
11 SEPTEMBER 2025

August key points
In the month to 8 September 2025, national hydro storage decreased from 87% to 79% of historical average.
South Island storage decreased to 73% of average and North Island storage decreased to 98% of average by 8 September
2025.
Meridian’s August 2025 monthly total inflows were 73% of historical average.
Waiau catchment inflows in August 2025 were 67% of historical average.
Meridian’s Waitaki catchment water storage at the end of August 2025 was 65% of historical average.
Snow storage in Meridian’s Waitaki catchment was 78% of average in early September 2025.
Water storage in Meridian’s Waiau catchment was 84% of average at the end of August 2025.
August was a dry and cool month, with both rainfall and temperatures below average for most of the country.
National electricity demand in August 2025 was 5.9% higher than August 2024.
New Zealand Aluminium Smelters (NZAS) average load during August 2025 was 565MW.
Meridian’s retail sales volumes in August 2025 were 12.8% higher than August 2024.
Compared to August 2024, segment sales in residential were 35.3% higher (including Flick customers), small medium business
7.2% higher, large business 14.6% higher, agriculture 2.2% higher and corporate 4.3% higher.
11 SEPTEMBER 2025MONTHLY OPERATING REPORT FOR AUGUST 2025
PAGE 2

2,600
2,800
3,000
3,200
3,400
3,600
3,800
4,000
4,200
JanFebMarAprMayJunJulAugSepOctNovDec
GWh
National demand
Range (2014-2024)202020212022202320242025
5%
7%
9%
11%
13%
15%
Jul 20Jan 21Jul 21Jan 22Jul 22Jan 23Jul 23Jan 24Jul 24Jan 25Jul 25
12 month average
Market ICP switching (all retailers)
Industry Move-in SwitchIndustry Trader Switch
Market data
National electricity demand in August 2025 was 5.9%
higher than August 2024.
NZAS average load during August 2025 was 565MW.
August was a dry and cool month, with both rainfall and
temperatures below average for most of the country.
Demand in the last 12 months was 2.5% lower than the
preceding 12 months.
12-month average switching rate of customers changing
retailers but not moving (“trader” switch) was 5.5% at the
end of July 2025.
12-month average switching rate of customers moving
and changing retailers (“move-in” switch) was 13.8% at
the end of July 2025.
11 SEPTEMBER 2025MONTHLY OPERATING REPORT FOR AUGUST 2025
PAGE 3
Source: Electricity Authority
Source: Electricity Authority

0
1,000
2,000
3,000
4,000
5,000
JanFebMarAprMayJunJulAugSeptOctNovDec
GWh
National hydro storage (8 September 2025)
Average storage (92yr)19922004200820122022202320242025
0
50
100
150
200
250
300
Q3
2025
Q4
2025
Q1
2026
Q2
2026
Q3
2026
Q4
2026
Q1
2027
Q2
2027
Q3
2027
Q4
2027
Q1
2028
Q2
2028
Q3
2028
Q4
2028
$/MWh
Benmore ASX futures settlement price
28 June 202430 May 202511 June 2025
10 July 202513 August 20258 September 2025
0
50
100
150
200
250
300
Q3
2025
Q4
2025
Q1
2026
Q2
2026
Q3
2026
Q4
2026
Q1
2027
Q2
2027
Q3
2027
Q4
2027
Q1
2028
Q2
2028
Q3
2028
Q4
2028
$/MWh
Otahuhu ASX futures settlement price
28 June 202430 May 202511 June 2025
10 July 202513 August 20258 September 2025
Market data
August 2025 saw decreases in ASX electricity futures prices
across the curve.
National storage decreased from 87% of average on 11
August 2025 to 79% of average on 8 September 2025.
South Island storage decreased to 73% of historical
average by 8 September 2025 and North Island storage
decreased to 98% of average.
11 SEPTEMBER 2025
Weekly lake storage updates are available on Meridian’s website. See comparative lake levels at:
www.meridianenergy.co.nz/power-stations/lake-levels
MONTHLY OPERATING REPORT FOR AUGUST 2025
PAGE 4
Source: NZX
Source: ASXSource: ASX

131
149
134
152
145
149
123
124
124
125
125
126
126
127
128
129
129
130
127
127
127
128
128
129
129
130
131
132
132
133
119
121
122
124
126
128
132
134
136
137
139
142
0
100
200
300
400
500
JulAugSepOctNovDecJanFebMarAprMayJune
ICPs ('000)
Meridian's customer connections
FY26 Meridian NIFY26 Meridian SIFY26 Powershop
FY25 Meridian NIFY25 Meridian SIFY25 Powershop
233
259
173
171
55
82
75
75
315
328
201
191
158
144
125
123
122
111
127
138
172
201
159
159
137
133
130
129
128
127
138
133
154
153
54
80
88
116
167
196
133
167
94
77
67
49
61
65
57
62
56
56
56
52
59
59
67
68
303
314
303
321
326
336
348
333
367
331
337
302
0
250
500
750
1,000
JulAugSepOctNovDecJanFebMarAprMayJune
GWh
Meridian's retail sales volume*
FY26 ResidentialFY26 SMBFY26 AgriFY26 Large BusFY26 Corporate
FY25 ResidentialFY25 SMBFY25 AgriFY25 Large BusFY25 Corporate
Retail
Meridian’s customer connection numbers increased 9.6% during
August 2025 and have increased 21.2% since August 2024.
Retail sales volumes in August 2025 were 12.8% higher than August
2024.
Compared to August 2024, segment sales in residential were 35.3%
higher, small medium business 7.2% higher, large business 14.6%
higher, agriculture 2.2% higher and corporate 4.3% higher.
To date this financial year, retail sales volumes are 11.1% higher
than the same period last year.
Compared to last financial year, segment sales in residential are
25.3% higher, small medium business 7.9% higher, large business
18.1% higher, agricultural 2.7% higher and corporate 4.2% higher.
Residential sales from August 2025 include Flick customers.
11 SEPTEMBER 2025
*excludes volumes sold to New Zealand Aluminium Smelters Limited and CFDs
MONTHLY OPERATING REPORT FOR AUGUST 2025
PAGE 5
Meridian operating information
Source: Meridian
Source: Meridian

0
500
1,000
1,500
2,000
2,500
3,000
2011201220132014201520162017201820192020202120222023202420252026
GWh
Financial
year
Meridian's combined catchment inflows
Aug YTD93 year average
0
500
1,000
1,500
2,000
2,500
1-Jan1-Feb1-Mar1-Apr1-May1-Jun1-Jul1-Aug1-Sept1-Oct1-Nov1-Dec
GWh
Meridian's Waitaki storage
Average 1979-2019202020212022202320242025
Inflows and storage
August 2025 monthly total inflows were 73% of historical average.
Waiau catchment inflows in August 2025 were 67% of historical
average, 46% lower than the same month last year.
To date this financial year, inflows are 80.5% of historical average.
Waitaki catchment water storage moved from 1,210GWh to
734GWh during August 2025.
Waitaki water storage at the end of August 2025 was 65% of
historical average and 34% higher than the same time last year.
Snow storage in Meridian’s Waitaki catchment was 78% of
average in early September.
Water storage in Meridian’s Waiau catchment was 84% of average
at the end of August 2025.
11 SEPTEMBER 2025
Weekly lake storage updates are available on Meridian’s website. See comparative lake levels at:
www.meridianenergy.co.nz/power-stations/lake-levels
MONTHLY OPERATING REPORT FOR AUGUST 2025
PAGE 6
Meridian operating information
Source: Meridian
Source: Meridian

0
100
200
300
400
500
JulAugSepOctNovDecJanFebMarAprMayJun
$/MWh
Meridian's average generation price*
FY26FY25
0
200
400
600
800
1,000
1,200
1,400
JulAugSepOctNovDecJanFebMarAprMayJun
GWh
Meridian's generation
FY26 HydroFY26 WindFY25 HydroFY25 Wind
Generation
Meridian’s generation in August 2025 was 22.1% higher than the
same month last year, reflecting higher hydro generation
andlower wind generation.
To date this financial year, Meridian’s generation is 15.6% higher
than the same period last year, reflecting higher hydro generation
and lower wind generation.
The average price Meridian received for its generation in August
2025 was 63.6% lower than the same month last year.
The average price Meridian paid to supply customers in August
2025 was 62.9% lower than the same month last year.
This date this financial year, the average price Meridian received
for its generation is 66.7% lower than the same period last year and
the average price paid to supply customers is 65.9% lower.
11 SEPTEMBER 2025
*price received for Meridian’s physical generation
MONTHLY OPERATING REPORT FOR AUGUST 2025
PAGE 7
Meridian operating information
Source: Meridian
Source: Meridian

Monthly operating information
11 SEPTEMBER 2025
See page 9 for footnotes
MONTHLY OPERATING REPORT FOR AUGUST 2025
PAGE 8
Meridian operating information
AUGUSTAUGUSTJULYJUNE2 MONTHS TO2 MONTHS TO
2025202420252025AUGUSTAUGUST
MONTHMONTHMONTHMONTH20252024
New Zealand contracted sales
Residential sales v olume (GWh)259 191 233 201 492 392
Small medium business sales v olume (GWh)171 159 173 153 343 318
Agricultural sales v olume (GWh)82 80 55 49 137 133
Large business sales v olume (GWh)75 65 75 68 149 127
Corporate and industrial sales v olume (GWh)328 314 315 302 643 617
Retail contracted sales volume (GWh)913 810 850 773 1,764 1,587
Av erage retail contracted sales price
1
( $N Z/ MWh)$172.5$162.9$172.4$165.6$172.4$162.6
NZAS sales v olume (GWh)276 261 267 241 542 588
Financial contract sales v olumes
2
(GWh)349 222 418 281 767 517
Av erage w holesale & financial contracts sales price
3
( $N Z/ MWh)$116.4$127.5$117.1$119.5$116.7$128.3
Retail customer supply v olumes (GWh)949 866 892 809 1,841 1,678
Cost to supply retail customers ($NZ/MWh)$184.4$487.4$113.3$131.8$149.9$436.7
Cost to supply w holesale customers ($NZ/MWh)$186.2$509.9$102.2$121.2$144.9$442.6
Cost of financial contracts ($NZ/MWh)$171.5$494.8$105.1$126.6$135.3$425.6
BESS supply v olume (GWh)2 - 1 1 2 -
Cost to supply BESS ($NZ/MWh)$138.1$0.0$86.5$133.2$122.6$0.0
Demand response payments ($NZm)-$3.1-$19.1-$5.4-$18.3-$8.5-$23.8
Total New Zealand customer connections
4
450,317 371,479 410,865 405,072

Monthly operating information
11 SEPTEMBER 2025MONTHLY OPERATING REPORT FOR AUGUST 2025
PAGE 9
Meridian operating information
Footnotes
1.Contracted sales volumes and volume weighted average price received from contracted
customers less distribution costs.
2.Derivatives sold excluding the sell-side of virtual asset swaps.
3.Average price of both NZAS sales volume and derivative sales volumes.
4.Meridian Retail and Powershop New Zealand installation control points (ICPs), excluding vacants.
5.Volume weighted average price received for Meridian’s physical generation.
6.Over the counter and ASX contract volumes excluding the buy-side of virtual asset swaps.
AUGUSTAUGUSTJULYJUNE2 MONTHS TO2 MONTHS TO
2025202420252025AUGUSTAUGUST
MONTHMONTHMONTHMONTH20252024
New Zealand generation
Hydro generation v olume (GWh)1,030 773 1,022 925 2,052 1,700
Wind generation v olume (GWh)148 192 135 148 283 321
BESS generation v olume (GWh)1 - 0 0 1 -
Total generation volume (GWh)1,179 965 1,157 1,073 2,337 2,021
Av erage generation price
5
($NZ/M Wh)$176.6$483.8$108.1$121.0$142.7$427.5
New Zealand hedging
Hedging v olume
6
(GWh)472 451 473 379 945 902
Hedging cost av erage price ($NZ/M Wh)$218.2$226.1$215.9$200.6$217.1$200.3
Hedging spot rev enue av erage price ($NZ/MWh)$174.2$451.9$107.4$126.8$140.8$399.3
Future contract close outs ($NZm)-$1.0-$13.7-$0.7-$0.6-$1.7-$26.6
New Zealand costs
Employee and Operating Costs ($m)24 25 24 26 48 51
Stay in Business Capital Expenditure ($m)5 6 3 19 8 9
I nv estment Capital Expenditure ($m)11 9 11 17 22 22
Total Capital Expenditure ($m)16 15 14 36 30 31

FY26 operating information
11 SEPTEMBER 2025MONTHLY OPERATING REPORT FOR AUGUST 2025
PAGE 10
Meridian operating information
JulAugSepOctNovDecJanFebMarAprMayJunQ1YoYQ2YoYQ3YoYQ4YoY
202520252025202520252025202620262026202620262025FY26changeFY26changeFY26changeFY26change
Retail contracted sales
Residential sales v olume (GWh)233 259
Small medium business sales v olume (GWh)173 171
Agricultural sales v olume (GWh)55 82
Large business sales v olume (GWh)75 75
Corporate and industrial sales v olume (GWh)315 328
Retail contracted sales volume (GWh)850 913
Av erage retail contracted sales price ($NZ/MWh)$172.4$172.5
NZAS sales v olume (GWh)267 276
Financial contract sales v olumes (GWh)418 349
Av erage w holesale & financial contracts sales price ($NZ/MWh)$117.1$116.4
Retail customer supply v olumes (GWh)892 949
Cost to supply retail customers ($NZ/MWh)$113.3$184.4
Cost to supply w holesale customers ($NZ/MWh)$102.2$186.2
Cost of financial contracts ($NZ/MWh)$105.1$171.5
BESS supply v olume (GWh)1 2
Cost to supply BESS ($NZ/MWh)$86.5$138.1
Demand response payments ($NZm)-$5.4-$3.1
Total New Zealand customer connections410,865 450,317
Generation
Hydro generation v olume (GWh)1,022 1,030
Wind generation v olume (GWh)135 148
BESS generation v olume (GWh)0 1
Total generation volume (GWh)1,157 1,179
Av erage generation price ($NZ/MWh)$108.1$176.6
Hedging
Hedging v olume (GWh)473 472
Hedging cost av erage price ($NZ/M Wh)$215.9$218.2
Hedging spot rev enue av erage price ($NZ/MWh)$107.4$174.2
Future contract close outs ($NZm)-$0.7-$1.0
Other
Employee and Operating Costs ($NZ m)2424
Stay in Business Capital Expenditure ($NZ m)35
I nv estment Capital Expenditure ($NZ m)1111
Total Capital Expenditure ($NZ m)1416

FY25 operating information
11 SEPTEMBER 2025MONTHLY OPERATING REPORT FOR AUGUST 2025
PAGE 11
Meridian operating information
JulAugSepOctNovDecJanFebMarAprMayJunQ1YoYQ2YoYQ3YoYQ4YoY
202420242024202420242024202520252025202520252025FY25changeFY25changeFY25changeFY25change
Retail contracted sales
Residential sales v olume (GWh)201 191 158 144 125 123 122 111 127 138 172 201 550 -5392 -1361 +4511 +17
Small medium business sales v olume (GWh)159 159 137 133 130 129 128 127 138 133 154 153 456 -1393 -1393 +0441 +15
Agricultural sales v olume (GWh)54 80 88 116 167 196 133 167 94 77 67 49 221 -20479 +25394 -160194 -31
Large business sales v olume (GWh)61 65 57 62 56 56 56 52 59 59 67 68 183 +9174 +19167 +5193 +23
Corporate and industrial sales v olume (GWh)303 314 303 321 326 336 348 333 367 331 337 302 920 -69983 -121,048 +53970 +40
Retail contracted sales volume (GWh)777 810 743 776 805 839 787 791 786 738 798 773 2,330 -872,419 +312,363 -982,309 +65
Av erage retail contracted sales price ($NZ/MWh)$162.4$162.9$161.6$136.9$135.2$132.3$143.2$141.5$149.8$161.6$171.4$165.6$162.3+$12.7$134.8+$5.7$144.9+$7.6$166.3+8
NZAS sales v olume (GWh)327 261 233 265 275 303 249
239 247 236 243 241 821 -441842 -421735 -510720 -512
Financial contract sales v olumes (GWh)295 222 206 192 210 212 396 318 407 281 319 281 723 -357614 -701,121 +368881 -20
Av erage w holesale & financial contracts sales price ($NZ/MWh)$128.9$127.5$105.2$76.6$70.9$65.0$86.6$94.3$103.0$132.7$131.8$119.5$121.7+$43.9$70.6+$12.1$94.7+$21.9$128.1+38
Retail customer supply v olumes (GWh)813 866 766 818 858 877 835 834 821 776 825 809 2,444 -1172,554 +72,491 -932,409 +51
Cost to supply retail customers ($NZ/MWh)$382.7$487.4$93.0$62.8$36.6$27.6$123.8$269.8$308.7$334.8$214.8$131.8$329.0+$196.4$41.9-$110.0$233.6+$43.4$225.6-51
Cost to supply w holesale customers ($NZ/MWh)$388.9$509.9$68.2$49.3$23.3$19.2$117.1$269.1$324.0$345.1$205.2$121.2$336.4+$218.7$30.0-$105.0$236.0+$60.0$222.9-33
Cost of financial contracts ($NZ/MWh)$375.3$494.8$91.1$63.5$33.8$25.8$111.8$233.2$281.8$326.1$209.0$126.6$330.9+$211.4$40.3-$92.2$207.9+$31.6$220.1-36
BESS supply v olume (GWh)1 2 2 1 1 +14 +4
Cost to supply BESS ($NZ/MWh)$304.8$327.0$178.2$133.2$304.8$304.8$235.0$235.0
Demand response payments ($NZm)-$4.7-$19.1-$25.0-$18.7-$13.2-$8.8-$7.3-$5.0-$10.3-$10.7-$10.7-$18.3-$48.7-$48.7-$40.7-$40.7-$22.5-$22.5-$39.7-$39.7
Total New Zealand customer connections369,376 371,479 373,670 376,126 379,348 382,708 386,645 390,314 394,951 397,551 399,077 405,072 373,670 +8,217382,708 +10,908394,951 +21,619405,072 +35,405
Generation
Hydro generation v olume (GWh)927 773 825 929 1,030 1,079 1,086 940 792 745 895 925 2,524 -6823,037 +152,818 -1252,564 -391
Wind generation v olume (GWh)129 192 187 179 164 174 113 85 133 141 163 148
509 +147517 +159332 -36452 +99
BESS generation v olume (GWh)- - - - - - - - 0 1 1 0 - +0- +00 +02 +2
Total generation volume (GWh)1,056 965 1,012 1,107 1,194 1,253 1,199 1,025 925 886 1,058 1,073 3,033 -5353,554 +1743,149 -1613,018 -290
Av erage generation price ($NZ/MWh)$376.2$483.8$63.8$49.8$29.9$19.6$106.3$253.1$302.1$332.4$196.0$121.0$306.2+$187.2$32.5-$103.8$211.6+$34.7$209.4-$47.7
Hedging
Hedging v olume (GWh)451 451 432 403 277 331 416 433 492 453 422 379 1,334 -1681,011 -3471,341 -1051,253 -223
Hedging cost av erage price ($NZ/M Wh)$174.5$226.1$231.4$196.2$134.2$125.3$150.7$162.1$169.3$203.4$201.7$200.6$210.4+$72.6$156.0+$46.9$161.2+$28.3$202.0+$54.0
Hedging spot rev enue av erage price ($NZ/MWh)$346.6$451.9$79.1$61.2$34.7$35.9$124.8$245.7$293.4$313.0$204.2$126.8$295.5+$171.5$45.6-$103.1$225.7+$39.0$220.1-$37.7
Future contract close outs ($NZm)-$13.0-$13.7$2.3$6.9$0.4$0.1-$5.7-$5.9-$4.4$0.3-$2.0-$0.6-$24.4-43.0$7.4+8.0-$16.0-$16.6-$2.2$4.7
Other
Employee and Operating Costs ($NZ m)262530212323202125262426$80+$11$68-$3$65-$1$76-$0
Stay in Business Capital Expenditure ($NZ m)4647861486819$14+$0$20+$4$13-$10$33+$13
I nv estment Capital Expenditure ($NZ m)129111181854114317$32-$18$37-$46$10-$74$33-$26
Total Capital Expenditure ($NZ m)161515181624789201136$46-$18$57-$42$24-$83$66-$13

Glossary
Hedging volumesbuy-side electricity derivatives excluding the buy-side of virtual asset swaps
Average generation pricethe volume weighted average price received for Meridian’s physical generation
Average retail contracted sales pricevolume weighted average electricity price received from retail customers, less distribution costs
Average wholesale contracted sales pricevolume weighted average electricity price received from wholesale customers (including NZAS) and financial contracts
Combined catchment inflowscombined water inflows into Meridian’s Waitaki and Waiau hydro storage lakes
Cost of hedgesvolume weighted average price Meridian pays for derivatives acquired
Cost to supply contracted salesvolume weighted average price Meridian pays to supply contracted customer sales and financial contracts
Contracts for Difference (CFDs)an agreement between parties to pay the difference between the wholesale electricity price and an agreed fixed price for
a specified volume of electricity. CFDs do not result in the physical supply of electricity
Customer connections number of installation control points, excluding vacants
GWhgigawatt hour. Enough electricity for 125 average New Zealand households for one year
Historic average inflowsthe historic average combined water inflows into Meridian’s Waitaki and Waiau hydro storage lakes over the last 85 years
Historic average storagethe historic average level of storage in Meridian’s Waitaki catchment since 1979
HVDChigh voltage direct current link between the North and South Islands of New Zealand
ICPNew Zealand installation control points, excluding vacants
ICP switchingthe number of installation control points changing retailer supplier, recorded in the month the switch was initiated
MWhmegawatt hour. Enough electricity for one average New Zealand household for 46 days
National demandElectricity Authority’s reconciled grid demand www.emi.ea.govt.nz

NZASNew Zealand Aluminium Smelters Limited
Retail sales volumescontract sales volumes to retail customers, including both non half hourly and half hourly metered customers
Financial contract salessell-side electricity derivatives excluding the sell-side of virtual asset swaps
Virtual Asset Swaps (VAS)CFDs Meridian has with Genesis Energy and Mercury New Zealand. They do not result in the physical supply of electricity
11 SEPTEMBER 2025MONTHLY OPERATING REPORT FOR AUGUST 2025
PAGE 12