Atlantica Sustainable Infrastructure : First Quarter 2024 Results Presentation

Q1 2024

Earnings Presentation

May 8, 2024

DISCLAIMER

Forward Looking Statements

• This presentation 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 presentation, including, without limitation, those regarding our future financial position and results of operations, our strategy, plans, objectives, goals and targets, 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," "could", "estimate", "expect", "guidance", "may", "plan", "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 presentation and are not guarantees of future performance and are based on numerous assumptions. Our 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-lookingstatements include, but are not limited to, statements relating to: our anticipated exposure to current market risks, including the potential impact from foreign exchange rates and interest rates on cash available for distribution ("CAFD"); equity investments; CAFD estimates, including per currency, geography and sector; net corporate leverage based on CAFD estimates; debt refinancing; the performance of our long-term contracts; self-amortizing project debt structure and debt reduction; return from the recently acquired UK wind assets, sale of electricity under PPAs, investments in assets to be built and their respective ready to build ("Rtb") and commercial operation dates; proceeds expected from the sale of our equity interest in Monterrey; the use of non-GAAP measures as a useful tool for investors including enterprise value to EBITDA multiple; dividends; 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.
• The CAFD guidance used in this presentation was estimated as of May 8, 2024. This estimate is based on assumptions believed to be reasonable as of the date Atlantica Sustainable Infrastructure plc ("Atlantica", the "Company", "we" or "us") published its 2023 Financial Results. We disclaim any current intention to update such guidance, except as required by law.

Non-GAAP Financial Measures

• This presentation also includes certain non-GAAP financial measures, including Adjusted EBITDA, CAFD, CAFD per share and enterprise value to EBITDA. 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 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 presentation for a reconciliation of the non-GAAP financial measures included in this presentation 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, Adjusted EBITDA and enterprise value to EBITDA) in this presentation provides useful information to investors.
• In our discussion of operating results, we have included foreign exchange impacts in our revenue and Adjusted EBITDA growth. The constant currency presentation is not a measure recognized under IFRS and excludes the impact of fluctuations in foreign currency exchange rates. We believe that constant currency information provides valuable supplemental information regarding our results of operations. We calculate constant currency amounts by converting our current period local currency revenue and Adjusted EBITDA using the prior period foreign currency average exchange rates and comparing these adjusted amounts to our prior period reported results. This calculation may differ from similarly titled measures used by others and, accordingly, the constant currency presentation is not meant to be a substitute for recorded amounts presented in conformity with IFRS as issued by the IASB nor should such amounts be considered in isolation.

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Q1 2024 Earnings Presentation

Key Messages

Stable revenue at $242.9 million in Q1 2024 compared with $242.5 million in Q1 2023

Adjusted EBITDA 0.9%1 year-over-year decrease excluding the effect of the unscheduled outage at Kaxu

Operating Cash Flow 57.3% year-over-year increase up to $65.6 million

Signed a 15-year PPA for a 100 MW solar + storage project in California

Closed the acquisition of two wind assets in operation in the UK at 6.6x EV /

EBITDA2 multiple

(1) Excluding the estimated impact of $8.5 million in the first quarter of 2024 of the unscheduled outage at Kaxu that started in 2023, and net of insurance income related to this event. The plant restarted operations in mid-February 2024.

(2) EV ("Entreprise Value") is defined as Atlantica´s expected investment. EBITDA is calculated as the average Net Income for the for the years 2023 and 2022 after adding back depreciation, 3 amortization and impairment charges, income taxes, and interest expenses. See Reconciliation on page 26.

Q1 2024 Earnings Presentation

HIGHLIGHTS

Operating Results

US$ in million (except CAFD per share)

Revenue

Adjusted EBITDA

CAFD

CAFD per share1

First 3 Months

2024	2023	∆	Excluding
& Q1-2023
		Kaxu impact2
		Reported	CAFD One-off3

242.9 242.5 0.2%

164.2 174.2 (5.7)% (0.9)%2

50.9 61.0 (17)% (11)%3

0.44

0.53

(17)%

(11)%3

(1) CAFD per share is calculated by dividing CAFD for the period by the weighted average number of shares for the period (see reconciliation on page 25).

(2) Excluding the estimated impact of $8.5 million in the first quarter of 2024 of the unscheduled outage at Kaxu that started in 2023, and net of insurance income related to this event. The plant restarted operations in mid-February 2024.

(3) Excluding $4.1 million from the sale of part of our equity interest in our development company in Colombia to a partner in Q1 2023.

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Q1 2024 Earnings Presentation

HIGHLIGHTS

Performance by Region and Sector

US$ in million

Revenue

Adjusted

EBITDA

North America

Q1	Q1	∆
2024	2023

86.2 72.8 18%

	55.0	52.0	6%

By Region

South America

Q1	Q1	∆
2024	2023

44.7 43.7 2%

34.6

33.8

2%

		EMEA
	Q1	Q1	∆
2024	2023

112.0 126.0 (11)%

74.6

88.4

(16)%

By Sector

Revenue

Adjusted

EBITDA

Renewables

Q1	Q1	∆
2024	2023

162.2 172.6 (6)%

107.2

119.1

(10)%

Efficient Nat.

Gas & Heat

Q1	Q1	∆
2024	2023

36.0 27.4 31%

	23.3	22.6	3%

Transmission

	Lines
Q1	Q1	∆
2024	2023

30.5 28.8 6%

24.8

23.5

6%

	Water
Q1	Q1	∆
2024	2023

14.2 13.7 4%

8.9

9.0

(1)%

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Q1 2024 Earnings Presentation

KEY OPERATIONAL METRICS

Steady Operational Performance

Renewables

	Q1 2024	Q1 2023
GWh produced1 1,063	1,192
MW in	2,203	2,161
operation2

Efficient Natural Gas & Heat

	Q1 2024	Q1 2023
GWh produced3	636	600
Availability4	102.3%	94.9%
MW in operation5	398	398

Transmission Lines

	Q1 2024	Q1 2023
Availability4	100.0%	100.0%
Miles in	1,229	1,229
operation

Water

	Q1 2024	Q1 2023
Availability4	102.3%	100.8%
Mft3 in	17.5	17.5
operation2

1. Includes 49% of Vento II production since its acquisition. Includes curtailment in wind assets for which we receive compensation.
2. Represents total installed capacity in assets owned or consolidated at the end of the period, regardless of our percentage of ownership in each of the assets, except for Vento II, for which we have included our 49% interest.
3. GWh produced includes 30% share of the production from Monterrey.
4. Availability refers to the time during which the asset was available to our client totally or partially divided by contracted or budgeted availability, as applicable.

(5) Includes 43 MW corresponding to our 30% share in Monterrey and 55 MWt corresponding to thermal capacity from Calgary District Heating.

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Q1 2024 Earnings Presentation

CASH FLOW

Operating Cash Flow

First Quarter

US$ in million	2024
Adjusted EBITDA	164.2
Share in Adjusted EBITDA of unconsolidated affiliates	(12.5)
Net interest and income tax paid	(26.7)
Changes in working capital	(41.1)
Non-monetary adjustments and other	(18.3)
OPERATING CASH FLOW	65.6
Acquisitions of subsidiaries and entities under the equity method
(84.4)
and investments in assets under development and construction
Investments in operating concessional assets	(2.4)
Distributions from entities under the equity method & other	16.1
INVESTING CASH FLOW	(70.7)
FINANCING CASH FLOW	12.7
Net change in consolidated cash1	7.6

2023

174.2

(11.8)

(30.2)

(93.3)

2.8

41.7

(9.5)

(7.6)

18.0

0.9

(42.1)

0.4

(1) Consolidated cash as of March 31, 2024, increased by $3.8 million vs December 31, 2023, including FX translation differences of $(3.8) million.

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Q1 2024 Earnings Presentation

GROWTH UPDATE

Progress in Development & Construction Complemented by M&A

New PPA in

California

• 100 MW PV + storage1 project, with RTB expected in 2024
• 15-YearPPA with an investment grade offtaker

Acquisition of

2 Wind Assets

in the UK

• 32 MW wind representing a $66 million investment
• Regulated revenue2 and no project debt
• 6.6x EV/EBITDA3
• Return expected to be enhanced by use of existing NOLs carryforwards in the UK

Other Projects

• Signed PPA for Chile PV 3 including the battery storage expansion under construction (142 MWh)
• 27.5 MWDC / 22 MWAC PV project in Spain
• Closed sale of Monterrey4

(1)	100 MW storage for four hours.
(2)	The assets are regulated until 2033 and 2027, under the UKs green attribute regulations ("ROCs"). The assets also receive Renewable Energy Guarantees of Origin ("REGOs") until the end of their useful life.
(3)	EV ("Enterprise Value") is defined as Atlantica's investment in these two assets. EBITDA is calculated as the average Net Income for the for the years 2023 and 2022 after adding back depreciation, amortization
	and impairment charges, income taxes, and interest expenses. See Reconciliation on page 26.
(4)	Expected proceeds of approximately $43 million subject to final transaction costs, taxes and ongoing discussions with our partner. There is an earn-out mechanism that could result in additional proceeds for	8
	Atlantica of up to approximately $7 million between 2026 and 2028.

Appendix

Q1 2024 Earnings Presentation

SIZEABLE AND DIVERSIFIED ASSET PORTFOLIO

Portfolio Breakdown Based on Estimated CAFD1

69% Renewable

14% Eff. Natural Gas & Heat

13% Transmission Lines

4% Water

>50%

of Revenue non dependent on natural resource5

13years

Weighted Average

PPA Life Remaining4

38% North America

35% Europe

20% South America

7% RoW

~92%

of interest rates in project debt are fixed or hedged3

>90%Denominated

in USD or hedged1,2

(1)	Based on CAFD estimates for the 2024-2027 period as of May 8, 2024, for the assets as of December 31, 2023, including assets that have reached COD before May 8, 2024. See "Disclaimer - Forward Looking Statements".
(2) Euro denominated cash flows from assets in Europe, net of euro-denominated corporate interest payments and general and administrative expenses, are hedged through currency options on a rolling basis 100% for the next 12 months and 75% for the
	following 12 months.
(3)	Based on weighted outstanding debt as of March 31, 2024.	10
(4)	Calculated as weighted average years remaining as of March 31, 2024, based on CAFD estimates for the 2024-2027 period, including assets that have reached COD before May 8, 2024. See "Disclaimer - Forward Looking Statements".
(5)	Calculated as a % of Revenue from FY 2023. Revenues non-dependent on natural resources includes transmission lines, efficient natural gas and heat, water assets and approximately 76% revenues received by our Spanish assets.