Atlantica Sustainable Infrastructure : Integrated Annual Report 2023

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I N T E G R A T E D

A N N U A L

R E P O R T

Content

Atlantica in Two Minutes……….…………3

Our Purpose and Values……………..…….5

About This Report…………………..………...6

Strategic Report…………………..………..…11

Our Sustainable Business Model and

Strategy…………………………………………12

Events During the Period……………….20

Key Performance Indicators………….30

A Fair Review of the Business……….33

Financial Review……………………..…….38

Principal Risks and Uncertainties….56

ESG Materiality Analysis……………….74

Environmental Sustainability………..80

Social Sustainability…………………….117

Asset Management……………………..150

Innovation Management…………….154

Cybersecurity and Data Privacy…..155

Tax Management……………………….158

Section 172 Statement……………….160

Going Concern Basis………………….165

Governance…………………………………..167

Business Ethics…………………………….167

Sustainability Governance……………174

Directors' Report………………………….178

Audit Committee Report……………..198

Directors' Remuneration Report….204

Directors' Responsibilities

Statement…………………………………….230

Shareholder Engagement…………….232

Other Information……………………………233

Asset Portfolio……………………………….234

Definitions…………………………………….236

Reconciliations……………….……………..242

Global Reporting Initiative (GRI)

Content Index…………………….………….244

Sustainability Accounting Standards

Board (SASB) Index………………….……253

Environmental, Social and Other Key

Performance Indicators…………..……257

Independent Auditor's Report……..270

Consolidated Financial

Statements…………………………………..280

Company Financial Statements…...367

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Atlantica in Two Minutes123

Our Business

2023 Selected Financial and Operational Metrics

Revenue		Adjusted EBITDA		Cash available for
		Distribution
$1,100 Million		$795 Million
		$236 Million

Operating Profit

$342 Million

Dividends Paid per Share

$1.78

Renewable Energy

5,458 GWh Produced

Total Assets as of December 31, 2023

$8.7 bn

Renewable Generation Pipeline Growth

▲12% vs. 2022

1. 100% Contracted or regulated. Regulated revenues in Spain, Chile TL 3 and Italy and non-contracted nor regulated in the case of Chile PV 1 and Chile PV 3.
2. Based on CAFD estimates for the 2024-2027 period as of March 1, 2024, for the assets as of December 31, 2023, including assets that have reached COD before March 1, 2023.
3. We refer to section "Strategic Report" for further detail regarding the pipeline description.

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Our Values

Integrity, Compliance and Safety

Value Creation

Sustainability

Excellence and Efficiency

Collaborative Environment

Enabling the Energy Transition

Science Based Targets initiative (SBTi) approved target:

Reduce Scope 1 and 2 GHG emissions per kWh of energy generated by 70% by

2035 from a 2020 base year

Other Targets

• Reduce Scope 3 GHG emissions per kWh of energy generated by 70% by 2035 from a 2020 base year
• Achieve Net Zero GHG emissions by 2040
• Reduce non-GHG emissions per kWh of energy generated by 50% by 2035 from a 2020
• Reduce our water consumption per kWh of energy generated by 50% by 2035 from a 2020 base year
• Reduce our hazardous and non-hazardous waste4 per unit of energy generated by 30% and 40%, respectively, by 2035 from a 2023 base year.

Key KPIS

EU Taxonomy

assessment: 97% of CapEx invested in sustainable activities according to EU Taxonomy.

GHG Emissions	GHG Emissions
Avoided	Offset
7.0 million tons of	380 thousand tons of
CO2e	CO2e
	▲ 23% vs 2021

Scope 1&2 emission rate per unit of energy generated

162 tons of gCO2/kWh

Improved 9% vs 2021

	2023 Selected Social Metrics
Employees	83% Men
1,366 people	17% Women
▲40% vs 2022	▲22% women vs 2022

Health and Safety: LTFI5 and TRFI4 below sector average

• LTFI and TRFI Decreased vs. 2022

Training hours per employee

33 as of Dec. 2023

Local Communities

$1.5 million invested

1. The target does not include the waste generated during end-of-life decommissioning of the assets.
2. We refer to section "Occupational Health and Safety" for further detail.

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Our Purpose and Values

Our Purpose

Our purpose is to support the transition towards a more sustainable world by developing, building, investing in and managing sustainable infrastructure assets, while creating long-term value for our stakeholders.

Our Values

Our values define who we are and how we behave both as individuals and as a Company. These values, described below in order of importance, serve as a compass for our day-to-day decisions and guide our relationships with stakeholders.

Integrity, Compliance and Safety. We will always do what isright. We are strongly committed to complying with all rules and regulations.

Value creation. We pursue a proactive approach to creating long-term value for our shareholders. Our core corporate policies are supported by a solid commitment to risk management that guides all our decisions.

Sustainability. We invest in assets that are environmentally sustainable and we manage them in a sustainable manner. Wefollow policies that analyse, evaluate, and propose measures aimed at minimising the environmental impacts of our business activity.

Excellence and Efficiency. We believe in outstanding and disciplined asset management of our operations to be the best- in-classoperator, while seeking excellence on a cost-efficientbasis.

Collaborative Environment. Respect and Teamwork are key to achieving our goals. We treat others as we would like to be treated ourselves and we put the team ahead of personal success. To buildstrong teams, we recruit, train, and promote the best people.

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About This Report

Atlantica Sustainable Infrastructure plc and its subsidiaries ("Atlantica" or "the Company"), as part of its commitment to transparency and reporting best practices, has published an Integrated Annual Report, which integrates our financial and non-financial information, including environment, social and governance (ESG) disclosures.

Integrated Annual Report Information

Atlantica's Integrated Annual Report has been prepared in accordance with the relevant U.K. requirements for the year ended December 31, 2023.

The Consolidated Financial Statements contained in this Report have been prepared in accordance with International Financial Reporting Standards as issued by the International Accounting Standards Board ("IASB") and UK adopted International Accounting Standards (collectively as "IFRS"), on a basis consistent with the prior year. The Parent Company Financial Statements have been prepared in conformity with Financial Reporting Standard 101 "Reduced Disclosure Framework ("FRS 101")". We refer to Note 2 to the Consolidated Financial Statements, and Note 1 to the Parent Company Financial Statements for accounting policies detailed information.

In addition, this report has been prepared by Management in accordance with the Global Reporting Initiative (GRI) Standards. We report GRI in line with the matters that are important and / or material to our business.

This report has also been prepared by Management in accordance with the SASB Electric Utilities

• Power Generators sustainability accounting standard and its reporting requirements. In addition, we have followed SASB Solar Technology & Project Developers sustainability accounting standards and its reporting requirements for aspects which are material to our business.

Data in this report for the year ended and as of December 31, 2023, except where otherwise noted. Comparative data for the years ended December 31, 2022, and 2021 is also provided. Our 2022, 2021 and 2020 Integrated Annual Report, U.K. Annual Reports and ESG Reports are available for download from our website.

ESG data reported corresponds to all consolidated subsidiaries. For Companies where Atlantica has joint financial control, we are consolidating the percentage of equity ownership for each of the ESG KPIs reported. Green House Gas emissions are accounted for following the financial control approach from the GHG Protocol. Emissions from joint ventures where partners have joint financial control are accounted for based on the equity share approach. We are accounting for proportional scope 1 and scope 2 emissions of equity investments in scope 3, category 15 (Investments).

A multi-disciplinary team participated in the preparation of this report. Currency amounts are expressed in U.S. Dollars unless otherwise noted.

ESG Data Review

Atlantica's management is responsible for the completeness, accuracy and validity of the information contained in this report. The data presented is based on the input received from internal data collection, management systems and external stakeholders. Certain parts of this report have been subject to external and/or internal assurance. We conduct regular internal audits to review our management system, including the procedures to collect information from our assets and the main data reported.

In 2023, independent third parties have been engaged to verify our reported Scope 1, 2 and 3 GHG emissions under a reasonable level of assurance.

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DNV, an independent expert in assurance and risk management, verifies all our reported Scope 1,

2 and 3 GHG emissions in all the geographies where we are present. In addition, we also hired:

• ANCE, a leading certification association across industries in Mexico, to verify Scope 1 and 2 greenhouse emissions in that geography,
• AENOR, a not-for-profit entity that fosters standardisation and certification across industrial and service sectors in Spain, to review our Scope 1 stationary GHG emissions in that geography.

In addition, DNV has also been engaged to verify Atlantica's air quality (i.e., non-GHG emissions), waste and water indicators and their compliance with GRI Reporting under a limited level of assurance.

In addition, in 2023 Atlantica's Internal Audit team reviewed the completeness and accuracy of certain environmental, social and governance performance indicators, including GHG emissions, water and waste management, health and safety, energy consumption, supply chain, people and culture and investment in local communities.

Furthermore, Atlantica's Accounting and Disclosure Committee reviewed this Integrated Annual Report prior to its publication.

Atlantica's Board of Directors approved this report prior to its publication.

Non-GAAP Financial Measures:

This report contains non-GAAP financial measures including Adjusted EBITDA, CAFD and CAFD per share.

Non-GAAP financial measures are not measurements of our performance or liquidity under IFRS and should not be considered alternatives to operating profit or profit for the period or any other performance measures derived in accordance with IFRS or any other generally accepted accounting principles or as alternatives to cash flow from operating, investing or financing activities. Please refer to the section "Other Information- Reconciliation of non-GAAP measures" of this report for a reconciliation of the non-GAAP financial measures included in this Report to the most directly comparable financial measures prepared in accordance with IFRS. Also, please refer to the following paragraphs in this section for an explanation of the reasons why management believes the use of non-GAAP financial measures (including CAFD, CAFD per share and Adjusted EBITDA) in this Report provides useful information to investors.

We present non-GAAP financial measures because we believe that they and other similar measures are widely used by certain investors, securities analysts and other interested parties as supplemental measures of performance and liquidity. The non-GAAP financial measures may not be comparable to other similarly titled measures employed by other companies and they may have limitations as analytical tools. These measures may not be fit for isolated consideration or as a substitute for analysis of our operating results as reported under IFRS as issued by the IASB. Non-GAAP financial measures and ratios are not measurements of our performance or liquidity under IFRS as issued by the IASB. Thus, they should not be considered as alternatives to operating profit, profit for the period, any other performance measures derived in accordance with IFRS as issued by the IASB, any other generally accepted accounting principles or as alternatives to cash flow from operating, investing or financing activities. Some of the limitations of these non-GAAP measures are:

Some of the limitations of these non-GAAP measures are:

• they do not reflect our cash expenditures or future requirements for capital expenditures or contractual commitments;
• they do not reflect changes in, or cash requirements for, our working capital needs;
• they may not reflect the significant interest expense, or the cash requirements necessary, to service interest or principal payments, on our debts;

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• although depreciation and amortisation are non-cash charges, the assets being depreciated and amortised will often need to be replaced in the future and Adjusted EBITDA, CAFD and CAFD per share do not reflect any cash requirements that would be required for such replacements; and
• the fact that other companies in our industry may calculate Adjusted EBITDA, CAFD and CAFD per share differently than we do, which limits their usefulness as comparative measures.

We define Adjusted EBITDA as profit/(loss) for the period attributable to the parent company, after adding back loss/(profit) attributable to noncontrolling interest, income tax expense, financial expense (net), depreciation, amortisation and impairment charges of entities included in our Annual Consolidated Financial Statements and depreciation and amortisation, financial expense and income tax expense of unconsolidated affiliates (pro-rata of our equity ownership). CAFD is calculated as cash distributions received by the Company from its subsidiaries minus cash expenses of the Company, including third-party debt service and general and administrative expenses and including proceeds from the sale of assets. CAFD per share is calculated as CAFD divided by the weighted average number of outstanding ordinary shares of the Company during the period.

Our management believes Adjusted EBITDA, CAFD and CAFD per share are useful to investors and other users of our financial statements in evaluating our operating performance because such measures provide investors with additional tools to compare business performance across companies and across periods. Adjusted EBITDA is widely used by investors to measure a company's operating performance without regard to items such as interest expense, taxes, depreciation and amortisation, which can vary substantially from company to company depending upon accounting methods and book value of assets, capital structure and the method by which assets were acquired. Our management believes CAFD and CAFD per share are relevant supplemental measure of the Company's ability to earn and distribute cash returns to investors and is useful to investors in evaluating our operating performance because securities analysts and other interested parties use such calculations as a measure of our ability to make quarterly distributions. In addition, CAFD and CAFD per share are used by our management team for determining future acquisitions and managing our growth. Our management uses Adjusted EBITDA, CAFD and CAFD per share as measures of operating performance to assist in comparing performance from period to period and aims to use them on a consistent basis moving forward. They also readily view operating trends as a measure for planning and forecasting overall expectations, for evaluating actual results against such expectations, and for communicating with our board of directors, shareholders, creditors, analysts and investors concerning our financial performance. Adjusted EBITDA, CAFD and CAFD per share are widely used by other companies in the same industry.

Information presented as the pro rata share of our unconsolidated affiliates reflects our proportionate ownership of each asset in our portfolio that we do not consolidate and has been calculated by multiplying our unconsolidated affiliates' financial statement line items by the Company's percentage ownership thereto. Note 7 to the Annual Consolidated Financial Statements includes a description of our unconsolidated affiliates and our pro rata share thereof. We do not control the unconsolidated affiliates. Multiplying our unconsolidated affiliates' financial statement line items by the Company's percentage ownership may not accurately represent the legal and economic implications of holding a non-controlling interest in an unconsolidated affiliate. We include depreciation and amortisation, financial expense and income tax expense of unconsolidated affiliates (pro rata of our equity ownership) because we believe it assists investors in estimating the effect of such items in the profit/(loss) of entities carried under the equity method (which is included in the calculation of our Adjusted EBITDA) based on our economic interest in such unconsolidated affiliates. Each unconsolidated affiliate may report a specific line item in its financial statements in a different manner. In addition, other companies in our industry may calculate their proportionate interest in unconsolidated affiliates differently than we do,

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limiting the usefulness of such information as a comparative measure. Because of these limitations, the information presented as the pro rata share of our unconsolidated affiliates should not be considered in isolation or as a substitute for our or such unconsolidated affiliates' financial statements as reported under applicable accounting principles. Please refer to "Other Information" section for additional information regarding reconciliations from non-GAAP measures.

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R E N E W A B L E E N E R G Y - S O L A R

1,590 MW IN OPERATION

23 ASSETS

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