Colbún S A : Earning Release 1T23

QUARTERLY EARNINGS

REPORT

As of March 31, 2023

1st QUARTER 2023

CONTENTS

1Q23 Earnings Report

Conference Call

1Q23 Results

Date: Friday April 28th, 2023

Hour: 12:00 PM Eastern Time

12:00 PM Chilean Time

USA: [phone]

Chile: [phone]

Event Link:

https://vndr.closir.com/room/276724

HIGHLIGHTS	3
PHYSICAL SALES AND GENERATION BALANCE	5
Physical sales and generation balance Chile	5
Physical sales and generation balance Peru	7
INCOME STATEMENT ANALYSIS	8
Operating Income analysis Generation Chile	9
Operating Income analysis Peru	10
Consolidated Non-Operating Result analysis	11
CONSOLIDATED BALANCE SHEET ANALYSIS	12
CONSOLIDATED FINANCIAL RATIOS	14
CONSOLIDATED CASH FLOW ANALYSIS	16
ENVIROMENT AND RISKS ANALYSIS	17
Medium-term outlook in Chile	17

Medium-term outlook in Peru	18
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Growth plan and long-term actions
20
Risk Management

Investor Relations Team Contact:

Miguel Alarcón V.	Isidora Zaldívar S.	Macarena Güell M.
[e-mail]	[e-mail]	[e-mail]
+ (56) 2 24604394	+ (56) 2 24604308	+ (56) 224604084

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1. HIGHLIGHTS

Main Figures at a Consolidated Level

Operating income for the first quarter of 2023 (1Q23) amounted to US$554,6 million, increasing 33% compared to operating income recorded in the first quarter of 2022 (1Q22), mainly due to (1) higher revenues from sales to unregulated clients in both countries, Chile and Peru, (2) higher revenues from the sale of energy and capacity in the spot market in Chile and (3) higher revenues from sales to regulated clients in both countries, Chile and Peru.

Consolidated EBITDA for 1Q23 reached US$192.2 million, increasing 32% compared to the US$145.6 million EBITDA in 1Q22. This increase is mainly explained by the higher income from ordinary activities mentioned above. This effect was partially offset by an increase in the costs of raw materials and consumables used.

Non-operatingresult in 1Q23 recorded losses of US$19.3 million, compared to the US$30.5 million loss recorded in 1Q22, mainly associated the higher financial incomes, because of the higher cash surpluses investment rates.

In 1Q23, a tax expense of US$30.4 million was recorded, compared to tax revenue of US$6.4 million in 1Q22. The increase in tax expense is mainly explained due to (1) the higher profit before taxes recorded during the period, and (2) the appreciation of the PEN/USD exchange rate during the first quarter of 2022 (1Q22), and its impact on the deferred. This is mainly explained given that Fenix's tax accounting is in Peruvian Soles, in accordance with Peruvian tax legislation.

In 1Q23, the Company presented a profit of US$91.9 million, compared to a US$55.9 million loss recorded in 1Q22, mainly due to (1) the higher EBITDA recorded in the period and (2) the lower non-operating loss, previously mentioned.

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Highlights of the quarter

On March 31, the Company reached 47% completion of Horizonte wind project. Specifically, during 1Q23, the assembly of the turbines began, reaching mechanical completion of the first 2 wind turbines. In addition, the construction of internal roads, platforms and foundations of the wind turbines is still in progress, with an advance of 63%, as well as the substations, transmission lines and medium voltage networks, with an advance of 52%. In total, 156 main components have been unloaded to date at the wind turbine site, including blades, towers, hubs, and generators.

During the quarter, the Company requested to the National Electric Coordinator to perform the real-time signal tests (SITR for its spanish acronym) of Diego de Alamagro's batteries for their certification. During this first quarter, the batteries are in the final phase of their commissioning and will have a capacity of 8 MW for 4 hours.

On March 28, the Board of Directors agreed to propose to the Ordinary Shareholders' Meeting to distribute a total final dividend of US$147.98 million, consisting of: (1) a final dividend of US$64.4 million, which added to the US$83.5 million paid in December 2022 represents 50% of the distributable net income for the year 2022, and (2) an additional dividend of US$75 million.

Subsequent highlights

On April 24, the Company received US$116.4 million from Alfa Desarrollo SpA corresponding to the final price adjustment associated with the Colbún Trasmisición S.A. shares sale, as agreed by the parties in the Purchase and Sale Agreement dated March 30, 2021, whose closing and payment was reported on August 10, 2021, leaving on that occasion a final adjustment price customary in this type of transaction.

By arbitration decision dated April 13, a claim of Puerto Coronel S.A. against Colbun S.A. was rejected, which sought to readjust the Santa María thermal power plant coal unloading tariffs, based on the income tax rate increase. On the other hand, by arbitration sentence dated April 18, Colbun S.A. lawsuit against Puerto Coronel S.A. was rejected, which had the purpose of demanding constituting compliance an operating company contractual obligation that manages the port assets and coal transportation to Santa María thermal power plant.

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• PHYSICAL SALES AND GENERATION BALANCE

2.1. Physical sales and generation balance in Chile

Table 1 shows a comparison between physical energy and capacity sales, and generation in 1Q22 and 1Q23.

Table 1: Physical sales and generation in Chile

Sales	Quarterly Figures	Var %
1Q22	1Q23	Q/Q
Total Physical Sales (GWh)	3,189	3,344	5%
Regulated Clients	549	621	13%
Unregulated Clients	2,400	2,403	0%
Sales to the Spot Market	240	320	33%
Capacity Sales (MW)	1,463	1,628	11%
Generation	Quarterly Figures	Var %
1Q22	1Q23	Q/Q
Total Generation (GWh)	3,250	3,445	6%
Hydraulic	804	956	19%
Thermal	2,195	2,274	4%
Gas	1,526	1,641	7%
Diesel	30	23	(24%)
Coal	638	611	(4%)
VRE*	251	216	(14%)
Wind Farm	33	19	(43%)
Solar	218	197	(10%)
Spot Market Purchases (GWh)	0	0	-
Sales - Purchases to the Spot Market (GWh)	240	320	-

(*): Includes energy purchased from Punta Palmeras

VRE: Variable renewable energies

Physical sales during 1Q23 reached 3,344 GWh, increasing 5% compared to 1Q22, mainly due to (1) higher sales to the spot market explained by the higher generation recorded in the quarter, and (2) higher sales to regulated clients mainly due to the expiration of regulated client contracts, which at the same time generate a higher load factor for those contracts that are still in force.

Additionally, generation for the quarter reached 3,445 GWh, increasing 6% compared to 1Q22, mainly due to (1) greater hydroelectric generation (+151 GWh) due to a greater thaw season compared to 1Q22, driven by a better hydrological condition during the year, and (2) greater gas generation (+114 GWh) associated with a higher availability of Argentinean gas coupled with higher availability of our gas-fired power plants. These effects were partially offset by lower energy purchases from third parties.

Spot market balance during the quarter registered net sales of 320 GWh, while in 1Q22 net sales of 240 GWh were recorded. This variation is mainly explained by the higher generation during the quarter.

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