Atlantica Sustainable Infrastructure : Reports FY 2023 Financial Results

Atlantica Reports 2023 Financial Results

• Net profit for 2023 attributable to the Company was $43.4 million, compared with a net loss of $5.4 million in 2022.
• Adjusted EBITDA for 2023 was $794.9 million, meeting guidance and representing a 1.7%1 increase versus 2022 on a comparable basis.
• Cash Available for distribution ("CAFD") was within guidance at $235.7 million.
• Continued progress on our development and construction activity with $175 to $220 million committed or earmarked for 2024 as of March 1 and a PPA signed with an investment grade utility for Overnight, a 150 MW PV project in California.
• 12% increase in renewable generation pipeline versus 2022.
• 2024 guidance initiated with Adjusted EBITDA in the range of $800 to $850 million and CAFD in the range of $220 million to $270 million.
• Strategic Review ongoing.

March 1, 2024 - Atlantica Sustainable Infrastructure plc (NASDAQ: AY) ("Atlantica" or the "Company" or "we") today reported its financial results for the year 2023. Revenue for 2023 was $1,099.9 million, a 0.2% decrease compared with 2022. Adjusted EBITDA was $794.9 million, representing a 1.7%1 increase versus 2022 on a comparable basis and a 0.3% decrease compared to 2022. CAFD was $235.7 million in 2023, a 0.9% decrease compared with $237.9 million in 2022. CAFD per share2 was $2.03, a 2.1% decrease compared to 2022.

1. Excluding the impact of FX and of the unscheduled outage at Kaxu in 2023, net of insurance income related to this event.
2. CAFD per share is calculated by dividing CAFD for the year by the weighted average number of shares for the year.

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Segment Results

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Operational KPIs

Production in the renewable energy portfolio increased by 2.6% during 2023 compared with 2022 mainly due to the increase in production in our solar assets in Spain, where solar radiation was higher, and to the contribution from the recently consolidated assets and those that have entered into operation recently. Production also increased in our U.S. solar assets mainly due to higher availability of the storage system at Solana. On the other hand, production in our wind assets in the U.S. decreased due to lower wind resource during 2023. Production also decreased in Kaxu mostly due to the unscheduled outage that started in September 2023. Part of the damage and the business interruption is covered by our insurance property policy, after a 60-day deductible.

Our efficient natural gas and heat assets, our water assets and our transmission lines, for which revenue is based on availability, continued at very high levels during 2023.

Liquidity and Debt

As of December 31, 2023, cash at Atlantica's corporate level was $33.0 million, compared with $60.8 million as of December 31, 2022. Additionally, as of December 31, 2022, the Company had $378.1 million available under its Revolving Credit Facility and therefore total corporate liquidity8 of $411.1 million, compared with $445.9 million as of December 31, 2022.

As of December 31, 2023, net project debt9 was $3.9 billion, compared with $4.0 billion as of December 31, 2022, while net corporate debt10 was $1,051.7 million, compared with $956.4 million as of December 31, 2022. As of December 31, 2023, the net corporate debt / CAFD pre-corporate debt service ratio11 was 3.8x.

1. Corporate liquidity means cash and cash equivalents held at Atlantica Sustainable Infrastructure plc as of December 31, 2023, and available revolver capacity as of December 31, 2023.
2. Net project debt is calculated as long-term project debt plus short-term project debt minus cash and cash equivalents at the consolidated project level.
3. Net corporate debt is calculated as long-term corporate debt plus short-term corporate debt minus cash and cash equivalents at Atlantica's corporate level.
4. Net corporate leverage is calculated as net corporate debt divided by 2023 CAFD before corporate debt service. CAFD pre- corporate debt service is calculated as CAFD plus corporate debt interest paid by Atlantica.

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Dividend

On February 29, 2024, the Board of Directors of Atlantica approved a dividend of $0.445 per share. This dividend is expected to be paid on March 22, 2024, to shareholders of record as of March 12, 2024.

Growth Update

2023 has been an important year to consolidate Atlantica's growth strategy through its own development engine complemented by acquisitions.

1. During the year, four PV assets from our development pipeline successfully reached COD.
2. Atlantica currently has three projects under construction or in an advanced development stage in California, levering on the Inflation Reduction Act:
3. • Coso Batteries 1 & 2, two standalone battery projects in California, with a combined storage capacity of 180 MWh. Both projects have PPAs signed with an investment grade utility and are currently under construction.
   • Overnight, a 150 MW PV project in California. In February 2024, we entered into a 15-year busbar PPA with an investment grade utility, under which Overnight is set to receive a fixed price per MWh, with no basis risk. We expect to include storage in a second phase of the project.

These three projects benefit from synergies with our existing assets and permit us to strengthen our strategic position in the Southwest.

3. In addition to our pipeline in the United States, we have opportunities in most of the geographies where we are present. In fact, we currently have other projects under construction, including PV plants and transmission line expansions in South America. The latter are a good example of expansions of assets in our existing portfolio, in a low risk sector where revenues are based on availability and indexed to inflation, and in geographies where we can find attractive returns.

As of March 1 and considering these and other opportunities, for 2024 Atlantica has already committed or earmarked investments in the range of $175-$220 million. We expect to complement this with new developments and acquisitions during the year.

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Atlantica currently has a pipeline of projects under development of approximately 2.2 GW12 of renewable energy and 6.0 GWh12 of storage. Our pipeline consists mostly of PV (47%), storage (41%) and wind (11%).

We also expect to have capital recycling opportunities. We are currently in the process of selling our 30% equity interest in Monterrey. Net proceeds after taxes are expected to be in the range of $45 to $52 million.13

2024 Guidance

Atlantica is initiating guidance for 2024:

• 2024 expected Adjusted EBITDA in the range of $800 million to $85014 million.
• 2024 expected CAFD in the range of $220 million to $270 million.

The CAFD guidance range is wider this year due to, among other reasons, several factors that are difficult to foresee as of today:

• The proceeds from the potential sale of Monterrey equity interest that we expect to close in the first half of 2024.

1. Only includes projects estimated to be ready to build before or in 2030 of approximately 3.7 GW, 2.2 GW of renewable energy and 1.5 GW of storage (equivalent to 6.0 GWh). Capacity measured by multiplying the size of each project by Atlantica's ownership. Potential expansions of transmission lines not included.
2. Our partner in Monterrey initiated a process to sell its 70% stake in the asset. Such process is well advanced and, as part of it, we intend to sell our interest as well under the same terms. The net proceeds to Atlantica are expected to be in the range of $45 to $52 million, after tax. The transaction is subject to certain conditions precedent and final transaction closing.
3. Adjusted EBITDA guidance includes a negative $45.0 million non-cash adjustment corresponding to the difference between billings and revenue in assets accounted for as concessional financial assets, primarily related to ACT, a negative non-cash provision of up to $2.6 million related to electricity prices in Spain and a

positive non-cash adjustment of $58.1 million corresponding to U.S. cash grants.

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• The unscheduled outage at Kaxu. Although we expect the business interruption to be covered by insurance after a 60-day deductible, the outage will affect distributions in 2024.
• Electricity market price volatility in Spain could affect distributions in 2024, to be compensated starting in 2026 according to the regulation.
• The level of collections at ACT could bring volatility to 2024 CAFD and this could have a positive or negative effect.

Details of the Results Presentation Conference

Atlantica's CEO, Santiago Seage and CFO, Francisco Martinez-Davis, will hold a conference call and a webcast on Friday, March 1, 2024, at 8:00 am (New York time).

In order to access the conference call participants should dial: +1-646-787-9445 (US), +44

1. 20-3936-2999 (UK) or +1-613-699-6539 (Canada), followed by the confirmation code 297018. Atlantica advises participants to access the conference call at least 15 minutes in advance.

The senior management team will also hold meetings with investors on March 4, at the Morgan Stanley Global Energy Power Conference in New York, on March 5, at the BofA Power, Utilities & Clean Energy Conference in New York, on March 18 at the Annual ROTH Conference in California, and on March 20, at the UBS Global Energy Transition Conference in London.

Forward-Looking Statements

This press release contains forward-looking statements. These forward-looking statements include, but are not limited to, all statements other than statements of historical facts contained in this press release, including, without limitation, those regarding our future financial position and results of operations, our strategy, plans, objectives, goals and targets, or future developments in the markets in which we operate or are seeking to operate. In some cases, you can identify forward-looking statements by terminology such as "anticipate," "believe," "continue," "could," "estimate," "expect," "guidance," "may", "potential", "should" or "will" or the negative of such terms or other similar expressions or terminology. By their nature, forward-looking statements involve risks and uncertainties because they relate to events and depend on circumstances that may or may not occur in the future. Forward-looking statements speak only as of the date of this press release and are not guarantees of future performance and are based on numerous assumptions. Our

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actual results of operations, financial condition and the development of events may differ materially from (and be more negative than) those made in, or suggested by, the forward- looking statements. Except as required by law, we do not undertake any obligation to update any forward-looking statements to reflect events or circumstances after the date hereof or to reflect anticipated or unanticipated events or circumstances.

Investors should read the section entitled "Item 3.D.-Risk Factors" and the description of our segments and business sectors in the section entitled "Item 4.B. Information on the Company-Business Overview", each in our Annual Report on Form 20-F for the fiscal year ended December 31, 2023, filed with the Securities and Exchange Commission ("SEC"), for a more complete discussion of the risks and factors that could affect us.

Forward-looking statements include, but are not limited to, statements relating to: our financing strategy; our investment plan, including our committed or earmarked investments for 2024; growth update and projects pipeline, our projects under construction or in advance development, as well as their synergies with existing assets; statements relating to leveraging the framework provided by the Inflation Reduction Act in the U.S.; our plans to sell certain assets; effects of business disruptions; CAFD estimates; corporate liquidity; equity investments; estimates and targets, ; the use of non-GAAP measures as a useful tool for investors; dividends; market and price volatility and various other factors, including those factors discussed under "Item 3.D.-Risk Factors" and "Item 5.A.-Operating Results" in our Annual Report on Form 20-F for the fiscal year ended December 31, 2023 filed with the SEC.

This communication mentions an ongoing strategic review. There can be no assurance that such strategic review will lead to the approval or completion of any transaction or other strategic change.

The CAFD, Adjusted EBITDA and other guidance incorporated into this press release are estimates as of March 1, 2024. These estimates are based on assumptions believed to be reasonable as of the date Atlantica published its 2023 Financial Results. We disclaim any current intention to update such guidance, except as required by law.

Non-GAAPFinancial Measures

This press release also includes certain 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 as issued by IASB and should not be considered alternatives to operating profit or profit for the period or net cash provided by operating

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activities or any other performance measures derived in accordance with IFRS as issued by the IASB or any other generally accepted accounting principles or as alternatives to cash flow from operating, investing or financing activities. Please refer to the appendix of this press release for a reconciliation of the non-GAAP financial measures included in this press release to the most directly comparable financial measures prepared in accordance with IFRS as well as the reasons why management believes the use of non-GAAP financial measures (including CAFD, CAFD per share, and Adjusted EBITDA) in this press release 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 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:

• they do not reflect our cash expenditures, 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;
• although depreciation and amortization are non-cash charges, the assets being depreciated and amortized 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;
• some of the exceptional items that we eliminate in calculating Adjusted EBITDA reflect cash payments that were made, or will be made in the future; 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.

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We define Adjusted EBITDA as profit/(loss) for the period attributable to the Company, after previously adding back loss/(profit) attributable to non-controlling interest, income tax, expense, financial expense (net), depreciation, amortization and impairment charges of entities included in the consolidated financial statements and depreciation and amortization, 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 debt service and general and administrative expenses plus realized dispositions gains and losses of ownership interest in assets. CAFD per share is calculated by dividing CAFD for the year by the weighted average number of shares for the year (116,151,646 for the year ended on December 31, 2023, and 114,694,880 for December 31, 2022).

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 it provides them with an additional tool 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 amortization, 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 measures of the Company's ability to earn and distribute cash returns to investors and are 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. Adjusted EBITDA, CAFD and CAFD per share are widely used by other companies in the same industry.

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.

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