GREENHOUSE GAS EMISSIONS INVENTORY REPORT

GREENHOUSE GAS EMISSIONS INVENTORY REPORT MERCURY’S CARBON FOOTPRINT 2015 TO 2021

PURPOSE OF DOCUMENT The purpose of this document is to provide an inventory of Mercury’s greenhouse gas emissions using the Greenhouse Gas Protocol and ISO14064-1 international standards for carbon accounting and reporting. Using these recognised frameworks ensures transparency, robustness and a consistent approach that will facilitate benchmarking with similar organisations and within the energy sector.

The report includes details of the unique emissions factors associated with Mercury’s geothermal generation facilities and its involvement in emissions trading and forestry offsets to communicate the comprehensive nature of Mercury’s response to the climate change challenge.

The document will also facilitate the additional disclosure of Mercury’s carbon footprint, review of risks and opportunities related to climate change, educate and inform interested stakeholders and meet some of the requirements of our annual submission to the Carbon Disclosure Project (CDP).

The CDP is a global voluntary carbon reporting programme that enables companies, cities, states and regions to measure and manage their environmental impacts. CDP’s network of investors represents over US$110 trillion in assets and uses CDP data and insights to make better-informed investment decisions.

Public disclosure of carbon data and the associated management of climate related risks and opportunities also enables Mercury to reflect the requirements of the Financial Standards Board’s Task Force on Climate-related Financial Disclosures (TCFD).

TCFD was established to develop voluntary, consistent climate-related financial risk disclosures for use by companies in providing information to investors, lenders, insurers, and other stakeholders. TCFD considers the physical, liability and transition risks associated with climate change and what constitutes effective financial disclosures across industries.

Mercury will disclose annually through CDP and use the resultant review and scoring to improve the management and reporting of our various responses to climate change.

Prepared by:

David Chua – Sustainability Strategy Analyst

DATE: 28 June 2022

Signed off by:

Lucie Drummond – GM Sustainability

DATE: 30 June 2022

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CONTENTS

1

GREENHOUSE GAS EMISSIONS INVENTORY SUMMARY .............................................................................4

2

INTRODUCTION ..................................................................................................................................................4

3

STATEMENT OF INTENT ....................................................................................................................................5

4

DESCRIPTION OF MERCURY ............................................................................................................................6 4.1

MERCURY ....................................................................................................................................................6

4.2

SUSTAINABILITY POLICIES, STRATEGIES AND PROGRAMMES ..........................................................6

5

PERSONS RESPONSIBLE ..................................................................................................................................6

6

REPORTING PERIOD COVERED .......................................................................................................................6

7

ORGANISATIONAL BOUNDARIES .....................................................................................................................6 7.1

8

CONSOLIDATION APPROACH ...................................................................................................................7

MERCURY FACILITIES .......................................................................................................................................7 8.1

Hydro Generation Facilities ..........................................................................................................................7

8.2

Geothermal Generation Facilities .................................................................................................................7

8.3

Other Facilities ..............................................................................................................................................8

9

OPERATIONAL BOUNDARIES AND INFORMATION MANAGEMENT PROCEDURES ...................................8 9.1

OPERATIONAL BOUNDARIES ...................................................................................................................8

9.2

INFORMATION MANAGEMENT PROCEDURES .......................................................................................8

10

SUMMARY OF EMISSIONS SOURCE INCLUSIONS .....................................................................................8

10.1

Other Emissions – PFCs ............................................................................................................................10

10.2

Other Emissions – CO2 emissions from the Combustion of Biomass .......................................................10

11

EMISSIONS SOURCE EXCLUSIONS ...........................................................................................................11

12

DATA COLLECTION, QUANTIFICATION AND UNCERTAINTIES ...............................................................11

12.1 13 13.1

IMPACT OF UNCERTAINTIES ..................................................................................................................11 THE BASE YEAR SELECTED .......................................................................................................................11 CHANGES TO THE HISTORIC BASE YEAR ............................................................................................11

14

GHG EMISSIONS CALCULATIONS AND RESULTS ....................................................................................11

15

GHG REMOVALS AND REDUCTIONS .........................................................................................................12

16

GHG LIABILITIES ...........................................................................................................................................12

17

COMPLIANCE WITH ISO14064-1 .................................................................................................................13

18

AUDIT OF THE GHG INVENTORY ................................................................................................................13

19

DESCRIPTION OF ADDITIONAL INDICATORS ...........................................................................................13

20

ASSESSMENT OF PERFORMANCE AGAINST RELEVANT BENCHMARKS ............................................13

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1

GREENHOUSE GAS EMISSIONS INVENTORY SUMMARY

SCOPE

CATEGORY

2015

2016

2017

2018

2019

2020

2021

Scope 1 direct emissions

Geothermal emissions for exported power

289,551

306,661

280,113

252,887

248,299

224,941

197,793

Thermal combustion (gas-fired generation)

167,525

63,518

-

-

-

-

-

457,256

370,179

280,113

252,887

248,299

224,941

197,793

461

492

485

449

458

281

316

1,712

36

1,611

27

70

85

63

98

26

26

10

10

1,890

1,943

143

140

134

101

103

1,762

1,650

459,490

370,873

282,369

253,474

248,908

228,959

201,765

57,293

54,513

57,356

63,392

62,009

67,104

66,576

n/r

n/r

1,510

989

241

1,468

-

320

196

317

386

320

1,677

1,064

Stay-in-business capital expenditure

n/r

n/r

n/r

n/r

n/r

109,359

17,119

General maintenance

n/r

n/r

n/r

n/r

n/r

3,629

4,991

IT Services

n/r

n/r

n/r

n/r

n/r

745

772

Print & Post

n/r

n/r

n/r

n/r

n/r

498

424

Office waste

n/r

n/r

n/r

n/r

n/r

11

17

Water & wastewater

n/r

n/r

n/r

n/r

n/r

1,719

1,399

517,403

425,582

341,552

318,241

311,510

415,169

294,127

Sub-total generation emissions Scope 1 – direct emissions contd.

Mobile combustion (company vehicle fleet) Stationary combustion (generation site plant and equipment)

Scope 2 – indirect emissions

Fugitive emissions (SF6 releases) Electricity consumption (location based)

Total Scopes 1&2 Scope 3 – indirect emissions

Use of sold products (gas sales) Drilling & development (onetime) Business travel / staff commuting

Total All Scopes

2

INTRODUCTION

Mercury New Zealand Limited (Mercury) is a 100% renewable electricity generator and retailer using natural resources such as hydro, geothermal and wind to provide our customers with low carbon electricity.

Mercury has a vision of energy freedom for the whole of New Zealand that will provide a national competitive advantage as the world transitions to a low-carbon future.

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This report covers Mercury’s greenhouse gas (GHG) inventory spanning seven financial years and is a complete and accurate quantification of the amount of GHG emissions that can be directly attributed to Mercury’s operations within the declared boundary and scope for the reporting period.

Under the New Zealand Emissions Trading Scheme (ETS) Mercury has unique emission factors produce by direct measurement of emissions from each geothermal facility. The entire process is also externally audited and assured, to a reasonable level of assurance, by Deloitte.

Emissions are measured monthly and are used for calculating total annual emissions and the required carbon units to retire. Mercury has invested in New Zealand forestry since 2010 and has long-term contracts in place. Carbon credits are then retired to cover fugitive, thermal scope 1 emissions and scope 3 downstream emission from customer gas sales. Mercury has also used ETS mechanisms such as the fixed price option and credits from projects to reduce emissions to meet these obligations.

3

STATEMENT OF INTENT

Mercury is intent on demonstrating transparency and uses commonly accepted standards when accounting for its greenhouse gas emissions. Therefore, this report relates specifically to the emissions of Mercury and follows international best practice protocols and standards, including ISO14064-1 and the Greenhouse Gas protocol: A corporate Accounting and Reporting Standard (2004) (the GHG Protocol).

The report has been prepared as part of an ongoing commitment to measure and manage emissions, educate and inform both internal and external stakeholders and facilitate continued discussions on carbon reduction targets and carbon neutrality.

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4

DESCRIPTION OF MERCURY

4.1

MERCURY

Mercury is an electricity retailer and generator that provides energy services to homes, businesses and industrial customers throughout New Zealand. Our mission is Energy Freedom and our goal is to inspire all New Zealanders to enjoy energy in more wonderful ways. Our electricity generation is therefore from 100% renewable sources, comprising nine hydro and five geothermal power stations. We retail to homes and business under the Mercury brand and other specialty brands, including the leading prepay service GLOBUG. To achieve energy freedom for New Zealand through the electrification of transport, we encourage the adoption of electric vehicles (EVs) and electric bikes (e.bikes) and partnering of non-home charging infrastructure and data.

4.2

SUSTAINABILITY POLICIES, STRATEGIES AND PROGRAMMES

“Sustainability at Mercury is about Energy Freedom, built on our five pillars of Commercial, People, Customer, Partnerships and Kaitiakitanga. Our history goes back almost one hundred years and we’ll be hear for at least a hundred more.”

Our five pillars of People, Commercial, Kaitiakitanga, Partnerships and Customer support a strategy integrating sustainable business practice by focussing on fifteen key areas; important to both mercury and our stakeholders.

Our strategy includes a long-term 2030 view of success for all fifteen focus areas, one of which is climate change.

Mercury has integrated sustainability into short-term FY22-24 business planning, moving the business towards long-term success. Under our Kaitiakitanga pillar, our vision for 2030 is: Mercury will be recognised as a leader in the ultra-long-term management of both physical and natural assets.

By 2022 we will be on track if: We are playing a leading role in New Zealand’s successful transition to a low-carbon economy.

5

PERSONS RESPONSIBLE

The person responsible for this GHG inventory is the GM Sustainability.

A team of people across Mercury are responsible for greenhouse gas accounting and reporting and have contributed to the creation of this report including: Sustainability Strategy Analyst, Geothermal Engineer, Environmental Advisor, Energy Analyst, SAS Technology Lead, Commercial Services Manager, Commercial Services Specialist, BI Business Analyst

6

REPORTING PERIOD COVERED

This GHG inventory covers the period 1st July 2014 to 30th June 2021.

7

ORGANISATIONAL BOUNDARIES

Mercury’s organisational boundary determines the parameters for GHG reporting and is set with reference to the GHG protocol and ISO14064-1 standards. The boundary encompasses the operations owned and controlled by Mercury, its subsidiaries, associate companies and joint ventures.

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7.1

CONSOLIDATION APPROACH

Mercury applies the operational consolidation approach to its greenhouse gas inventory. This allows Mercury to focus on the emissions where Mercury has operational control and can investigate the potential to manage and reduce. The table below sets out how each entity is treated: Table 2: Summary of entities and treatment of joint ventures

Entity Mercury NZ Limited

Tilt Renewables Limited TPC Holdings Ltd Rotokawa (Joint Venture) Nga Awa Purua (Joint Venture)

Principal Activity Electricity Generation (Hydro and geothermal), electricity retail Electricity generation (Wind) Investment Holding Steamfield Operation Electricity Generation

Type

Interest Held (end of FY21) 100%

Country

Included/Excluded

New Zealand

Included

Listed Company (NZX Main Board and ASX) Associate

19.96%

Australia and New Zealand

Excluded – no operational control

25%

New Zealand

Joint Operation

64.8%

New Zealand

Joint Operation

65%

New Zealand

Included – equity share Included – equity share Included – equity share

Listed Company (NZX Main Board)

8

MERCURY FACILITIES

8.1

Hydro Generation Facilities

Mercury owns nine stations on the Waikato River. Flexible and rain-fed, hydro output can be increased or decreased quickly and efficiently. They are listed in the table below.

Table 3: Hydro Generation Facilities

Facility Karapiro Arapuni Waipapa Maraetai I and II

First Operated 1947 1929 1961 1952 and 1970 respectively

Whakamaru Atiamuri Ohakuri Aratiatia

1956 1958 1961 1964

8.2

Description A 96MW plant with an average annual output of 511 GWh A 198MW plant with an average annual output of 872 GWh A 51MW plant with an average annual output of 242 GWh The two plants have a combined capacity of 360MW plant with an average annual output of 881 GWh A 124MW plant with an average annual output of 500 GWh A 84MW plant with an average annual output of 291 GWh A 112MW plant with an average annual output of 405 GWh A 90MW plant with an average annual output of 333 GWh

Geothermal Generation Facilities

Mercury operates five geothermal stations in the North Island. Providing steady baseload, geothermal runs at full capacity about 95% of the time.

Table 4: Geothermal Generation Facilities

Facility Kawerau Mokai Rotokawa Ngatamariki Nga Awa Purua

First Operated 2008 2000 2000 2013 2010

Description A 103MW flash plant with an average annual output of 831 GWh A 112MW flash plant with an average annual output of 800 GWh A 38MW binary cycle plant with an average annual output of 262 GWh A 82MW binary cycle plant with an average annual output of 705 GWh A 135MW flash plant with an average annual output of 1,132 GWh

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8.3

Other Facilities

Mercury has a 222MW wind farm under construction at Turitea with the first stage (119MW) becoming operational in January 2022. After the reporting period, Mercury also acquired the New Zealand operations of Tilt Renewables which included five operating wind farms with a combined capacity of 330MW, generating ~1,100 GWh p.a.

Other facilities also include offices in Auckland, Hamilton, Rotorua, Taupo and Wellington.

9

OPERATIONAL BOUNDARIES AND INFORMATION MANAGEMENT PROCEDURES (ISO 14064-1, 9.3.1 (D, E) AND 5.2)

9.1

OPERATIONAL BOUNDARIES

Mercury has used both the GHG Protocol and ISO 14064-1 standards to identify the emission sources required to complete this inventory. Accordingly, the emissions have been classified into: Scope 1 – Direct GHG emissions that are operationally controlled by the company; Scope 2 – Indirect emissions from the generation of purchased electricity; and Scope 3 – Indirect emissions that occur because of the activities of the company but from sources that are not owned and controlled by the company.

9.2

INFORMATION MANAGEMENT PROCEDURES

Mercury has developed robust GHG information systems to record fugitive geothermal emissions as these form most of its carbon footprint and have been required to meet its obligations under the Emissions Trading Scheme since 2010. The preparation of this emissions inventory report has prompted collation of additional, less material, datasets in a way that ensures ongoing conformance with GHG Protocol and ISO standards. Future emissions inventory reports will follow the same data collection and collation process, with opportunities taken to improve data integrity, completeness and emissions reporting accuracy.

10 SUMMARY OF EMISSIONS SOURCE INCLUSIONS Table 5: Summary of emissions source inclusions

Scope

Category

GHG emission source

Facilities included

Data source

Data collection unit

Method, data quality, uncertainty (qualitative)

1

Fugitive emissions

Fugitive emissions from geothermal generation

Kawerau, Mokai, Nga Awa Purua, Ngatamariki, Rotokawa

Geothermal Resources

Captured by Geothermal Resources team, audited

by Deloitte for ETS use, high quality data

1

Thermal emissions (historic)

Gas-fired thermal generation

Southdown

Records from sites, submitted as part of Emissions Trading Scheme requirements for the Crown Records from sites, submitted as part of Emissions Trading Scheme requirements for the Crown

Wholesale markets

Captured by Wholesale Markets, audited by Deloitte for ETS use, high quality data

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Scope

Category

GHG emission source

Facilities included

Data source

Data collection unit

Method, data quality, uncertainty (qualitative)

SF6 releases

SF6 releases during operations

Maintenance records (SF6 top ups) – Note: Stocks recorded as a liability

Environmental Team

Review of calendar year records, reasonable data quality, low level of uncertainty

Mobile combustion

Vehicle fleet fuel

Kawerau, Mokai, Nga Awa Purua, Ngatamariki, Rotokawa, Arapuni, Aratiatia, Atiamuri, Karapiro, Maraetai I and II, Ohakuri, Waipapa, Whakamaru Vehicle fleet

Commercial Services

Review of fuel card records, good data quality, very low level of uncertainty

Stationary combustion

Fuel used in generators and on-site plant and equipment

Hydro, Kawerau, Ngatamariki, Rotokawa

Fuel cards cover most of fuel purchases, there will be a limited number of purchases made by staff using cash/card Delivery company data

Commercial Services

2

Electricity – Offices

Electricity consumed in offices

Electricity internal category in financial records

Customer

2

Electricity generation sites

Grid electricity consumed at generation sites and Southdown

Auckland (x2), Wellington, Taupo, Rotorua, Southdown, Hamilton, Hydro and Southdown

SCADA extract

Wholesale markets

3

Use of sold products (including distribution losses)

Gas sales to customers (piped gas only) – note meter reading is subcontracted to data is difficult to obtain, readers work for more than one retailer so determining liability would be very difficult

Captured by Customer and Wholesale Markets

Gas sales records

Customer & Wholesale Markets

Review of delivery company data, good data quality Calculation based on internal invoicing, low level of uncertainty Calculation based on recorded data, low level of uncertainty but some lines consumption may not be Mercury’s Metered consumption from sales records from Customer so high-quality data, carbon is included in the offsets required under the ETS

1

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Scope

Category

GHG emission source

Facilities included

Data source

Data collection unit

Method, data quality, uncertainty (qualitative)

3

Drilling and development (one-time)

Fuel used in generators and on-site plant and equipment

Hydro, Kawerau, Ngatamariki, Rotokawa

Delivery company data

Commercial Services

3

Business travel, accommodation and staff commuting

All staff

Travel provider and Human Resources records

Commercial Services

3

Stay-In-Business Capital Expenditure

Kilometres flown by sector – domestic, short and longhaul and visitor nights by location. Head count for staff commuting Embodied emissions in capital goods purchased

Review of delivery company data, low level of uncertainty Low level of uncertainty, data integrity

All

General ledger vendor spend and GHG Protocol recognised database Quantis

Finance

3

General maintenance

Emissions associated with general maintenance

All

General ledger vendor spend and Motu emissions database

Finance

3

Print, Mail & Post

Emissions associated with creation and delivery of print, mail and post

All

General ledger vendor spend and Motu emissions database

Finance

3

Office Waste

Waste to landfill from offices can lead to methane production

All offices (extrapolated)

2021 waste audit of 33 Broadway (Auckland) office

Finance

3

Waste & Wastewater

Water and wastewater treatment can lead to greenhouse gas emissions

All offices (extrapolated)

Metered data from 33 Broadway (Auckland) office

Finance

10.1 10.1 Other Emissions – PFCs

Medium level of uncertainty due to $ spend dataset and use of US based emissions factor Medium level of uncertainty due to $ spend dataset and use of NZbased emission factor Medium level of uncertainty due to $ spend dataset and use of NZbased emission factor Low level of uncertainty due to $ spend dataset and use of NZbased emission factor Low level of uncertainty due to $ spend dataset and use of NZbased emission factor

(ISO 14064-1, 9.3.1(F)) Mercury does not use or hold PFCs so no emissions from these sources are included in this inventory.

10.2 Other Emissions – CO2 emissions from the Combustion of Biomass There was no combustion of biomass in Mercury’s operations during the reporting period.

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11 EMISSIONS SOURCE EXCLUSIONS (ISO 14064-1, 9.3.1(I)) The emissions sources below are excluded from Mercury’s GHG inventory reports. They are not considered material in the context of the inventory or to any of our specific stakeholders.

Table 6: Emissions Source Exclusions

Scope

Category

GHG emission source

Facilities included

Reason for exclusion

Scope 1

Refrigerant releases

All generation sites and office locations

Difficult to obtain data, considered immaterial

Scope 3

Land Use

HFCs from airconditioning systems Agricultural emissions

Mercury has very small landholdings around some of its hydro facilities which it leases to local farmers, mainly for grazing

Outside Mercury’s operational control, uncertain of methodology for calculating emissions and considered immaterial

12 DATA COLLECTION, QUANTIFICATION AND UNCERTAINTIES (ISO 14064-1, 9.3.1(M, N)) Data required to produce this emissions inventory comes from internal operational data, with the majority specifically measured as a ‘unique emissions factor’ determined by a third party as part of Mercury’s involvement in the ETS. The data is therefore robust and the unique emissions factor subject to external audit and assurance.

Datasets around scope 2 and 3 emissions are sourced from specific providers or from internal financial systems, both of which are robust systems. Quantification of the associated emissions currently uses spreadsheet to relate consumption to emissions factors. Emissions factors are sources from either New Zealand Government guidance documents, IPCC publications or recognised GHG emission databases.

12.1 IMPACT OF UNCERTAINTIES (ISO 14064-1, 9.3.1(P, Q)) The most significant source of emissions is from fugitive geothermal sources at geothermal generation sites which are subject to independent measurement therefore audit uncertainties within other datasets are considered to have no material impact on the resultant emissions inventory report.

13 THE BASE YEAR SELECTED (ISO 14064-1, 9.3.1(K)) The chosen base year is 1st July 2014 to 30th June 2015.

13.1 CHANGES TO THE HISTORIC BASE YEAR (ISO 14064-1, 9.3.1(L)) There has been no change to the historic base year.

14 GHG EMISSIONS CALCULATIONS AND RESULTS Emissions source datasets were gathered from across the business, from metered consumption points, financial records and from specific third-party suppliers such as liquid fossil fuel and travel providers.

The factors required to calculate the associated emissions were sourced from the Ministry for the Environment.

2020. Measuring Emissions: A Guide for Organisations: 2020 Detailed Guide. Wellington: Ministry for the Environment. The only exceptions being: a)

Emissions factor for Sulphur Hexaflouride (SF6) which was derived from the Fourth Assessment Report: Climate Change 2007 of the Intergovernmental Panel on Climate Change (IPCC)

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b)

Emissions factors for spend-based consumption which were sourced from the GHG Protocol database Quantis or Motu New Zealand’s environment input-output model. Both of these methods introduce some level of uncertainty as emissions factors are not always specific to New Zealand.

As seen in the graph in figure 1 below, Mercury’s emissions profile is dominated by Scope 1 emissions, namely fugitive emissions from geothermal electricity generation, which account for approximately two thirds of all emissions. Thermal emissions from the operation of a gas-fired power station reduced to zero in FY16 when the Southdown facility was decommissioned.

Scope 3 emissions from the sale of gas to Mercury customers and the emissions associated with the purchase of capital goods, measured through stay-in-business capital expenditure, are also material, although emissions related to stay-in-business capital expenditure vary over time. Other sources of emissions are considered immaterial.

Figure 1: Mercury Carbon Footprint 2014 to 2021 Scope 1 350,000 2015 300,000

2016 2017

Tonnes CO2e

250,000

2018 2019

200,000

2020

Scope 2 Scope 3

2021

150,000

100,000

50,000

Water & wastewater

Office waste

Mail, post and print

IT Services

General maintenance

Capital goods (stay-inbusiness)

Staff travel and commuting

Drilling & development (one-time)

Use of sold products (gas sales)

Electricity consumption (sites and offices)

SF6 releases

Stationary combustion (generation site plant and equipment)

Mobile combustion (company vehicles)

Thermal emissions

Geothermal fugitive emissions

0

15 GHG REMOVALS AND REDUCTIONS (ISO 14064-1, 9.3.1(H) AND 9.3.2 (E)) Over the reporting period Mercury has reduced its Scope 1 emissions by 57%, mainly due to the decommissioning of its Southdown gas-fired power station. Minor reductions have been seen at some of the geothermal generation sites due to the depletion of CO2 within the geothermal reservoirs over time

16 GHG LIABILITIES Mercury uses a gas, sulphur hexafluoride (SF6), in circuit breakers that has a global warming potential much higher than carbon dioxide. Its storage and use require annual audit under the Resource Management Act and as a matter of good practice.

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Total GHG holdings for the seven-year reporting period have been calculated and are provided in Table 7 below.

The significant decrease in holdings during 2020 is due to consolidation and centralisation of stored SF6 across Mercury sites.

Table 7: GHG Holdings

GHG Holdings

2015

2016

2017

2018

2019

2020

2021

SF6 Holdings (kg)

10,624

12,388

11,287

12,397

12,373

1,191

1,156

Mercury also has HFCs in refrigerators and some air conditions systems; these have been estimated as well below materiality thresholds so are not reported here.

17 COMPLIANCE WITH ISO14064-1 (ISO 14064-1, 9.3.1(R)) This GHG inventory report has been prepared in accordance with ISO 14064-1 and sections are appropriately referenced

18 AUDIT OF THE GHG INVENTORY (ISO 14064-1, 9.3.1(S)) The GHG inventory in its entirety has not been audited, however the fugitive emissions from Mercury’s geothermal operations are subject to monthly sampling and annual review and audit under the NZ ETS.

19 DESCRIPTION OF ADDITIONAL INDICATORS (ISO 14064-1, 9.3.2(H)) Mercury presents its generation emissions intensity and compares that to the New Zealand grid average 1 in Table 8.

20 ASSESSMENT OF PERFORMANCE AGAINST RELEVANT BENCHMARKS (ISO 14064-1, 9.3.2(H)) Mercury’s emissions intensity for its seven-year period is provided in Table 8 below and represented graphically on the following pages. Mercury’s emissions intensity is impacted by the volatility of hydro generation. The intensity calculation uses Scope 1 emission only, no adjustments have been made in relation to carbon trading conducted under the ETS. Table 8: GHG emissions, reductions and intensity calculations for Mercury’s electricity

GHG Holdings GHG Emissions – Scope 1 (tCO2e) Total annual reductions (tCO2e) Total reductions from base year (tCO2e) % Reduction from base year Total Generation (GWh) Emissions Intensity (kg CO2e/kWh) Emissions Intensity NZ grid electricity (kg CO2e/kWh) Annual reduction in emissions intensity Intensity reductions from base year

2015

2016

2017

2018

2019

2020

2021

459,347 6,535 0.070

370,733 88,614 88,614 19% 6,815 0.054

282,235 88,498 177,112 39% 7,513 0.038

253,373 28,863 205,975 45% 7,681 0.033

248,837 4,535 210,510 46% 6,880 0.036

224,941 23,896 234,406 49% 6,507 0.035

197,793 27,148 264,554 57% 6,380 0.031

0.119

0.119

0.119

0.110

0.113

0.101

0.101

-

23% 23%

31% 47%

12% 53%

-10% 49%

4% 51%

10% 56%

1

From Ministry for the Environment. 2020. Measuring Emissions: A Guide for Organisations: 2020 Detailed Guide. Wellington: Ministry for the Environment.

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Figure 2: Generation emissions intensity 2015 to 2021 9,000 8,000

0.12

7,000 0.10 6,000 0.08

5,000

0.06

4,000 3,000

Generation (GWh)

Emissions Intensity (kg CO2e/kWh)

0.14

0.04 2,000 0.02

1,000

0.00

0

2015

2016

Generation (RHS)

2017

2018 Financial Year

2019

Mercury Generation Emissions Intensity

2020

2021

NZ Grid Emissions Intensity

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