Colbún S A : Earning Release 3T23

QUARTERLY EARNINGS

REPORT

As of September 30, 2023

3rd QUARTER 2023

Conference Call

3Q23 Results

Date: November 3rd, 2023

Hour: 11:00 AM Eastern Time 12:00 PM Chilean Time

USA: [phone]

Chile: [phone]

Event Link:

https://mm.closir.com/slides?id=106945

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
Growth plan and long-term actions	19
Risk Management	21

Investor Relations Team Contact:

Miguel Alarcón V.	Federico Urgelles L.	Macarena Güell M.
[e-mail]	[e-mail]	[e-mail]
+ (56) 2 24604394	+ (56) 2 24604000	+ (56) 2 24604084

2

Operating income for the third quarter of 2023 (3Q23) reached US$493.8 million, increasing 1% compared to the revenues recorded during the third quarter of 2022 (3Q22), primarily due to (1) a higher average selling price to both unregulated and regulated clients in Chile, as a result of the positive variation in indexers in those contracts, and (2) a higher average price in the Peruvian spot market. These effects were partially offset by a lower average selling price in the Chilean spot market. In cumulative terms, ordinary operating income as of Sep-23 amounted to US$1,594.4 million, increasing 12% compared to Sep-22, mainly due to the same reasons that explain the variations in quarterly terms, especially the higher average selling price to unregulated clients in Chile compared to the previous year.

Consolidated EBITDA for 3Q23 reached US$226.2 million, increasing 10% compared to the US$205.2 million EBITDA in 3Q22. This increase is explained by a decrease in costs due to higher hydroelectric generation and consequently lower generation from thermal power plants during the quarter. Those effects were partially offset by (1) an increase in the costs of energy and power purchases in the spot market due to the higher average purchase price in Peru, and (2) lower revenue from the sale of energy and capacity in the spot market due to a lower average sell price in Chile. In cumulative terms, EBITDA as of Sep-23 totaled US$553.1 million, increasing 10% compared to Sep-22, mainly due to higher operating income, partially offset by higher raw materials and consumables costs.

Non-OperatingIncome in 3Q23 recorded a loss of US$0.5 million, which compares to the loss of US$34.2 million during 3Q22, mainly associated with (1) higher financial income due to the increase in interest rates during this quarter, and (2) higher "Other profits" mainly due to the income of US$8.3 million corresponding to an insurance payment, because of the Nehuenco 2 thermal power plant failure that occurred in January 2022. In cumulative terms, non-operating income as of Sep-23 reached profits of US$68.9 million, compared to a loss of US$105.5 million in Sep-22. The higher profit is mainly explained by the higher financial income previously mentioned, and the final price adjustment associated with the sale of Colbún Transmisión S.A for US$116.4 million, which was recorded during 2Q23.

In 3Q23, a tax expense of US$51.4 million was recorded, compared to a US$36.3 million tax expense in 3Q22. The increase is mainly explained by the higher pre-tax profit recorded during the period. This effect was partially offset by the appreciation of the Peruvian Sol during 3Q23 and its impact on deferred taxes. In cumulative terms, as of Sep-23, a tax expense of US$123.7 million was recorded, compared to US$61.7 million as of Sep-22, mainly due to the same reasons that explain the variations in quarterly terms.

In 3Q23, the Company recorded a profit of US$124.4 million, compared to US$80.7 million profit presented in 3Q22, mainly due to the higher EBITDA and non-operating income mentioned earlier. This impact was partially offset by the higher tax expenses in this period. In cumulative terms, Colbún presented a profit of US$347.6 million as of Sep-23, which compares with the US$174.3 million profit registered as of Sep-22, mainly due to the final price adjustment associated with the sale of Colbún Transmisión S.A for US$116.4 million, in addition to the increase in financial income.

3

On August 4, a fire broke out in the gas turbine filter area of Unit 1 at the Nehuenco Complex. The cause of the fire was the fall of an incandescent piece of metal into an area with flammable material filters, at a moment when the metal component was being welded to the structure of the filter area. However, it is important to note that this procedure is part of the major maintenance process that the mentioned Unit was undergoing at the time of the fire. Additionally, thanks to the action of the Complex's emergency brigade and the Quillota Fire Department, the fire was quickly contained without any injuries or spreading to other areas of the Complex. As a result, the estimated commissioning date for the unit is projected to be on January 20, 2024, a date that has already been communicated to the National Electric Coordinator. It should be noted that the Company has insurance for these types of events.

On September 12, the signing of a 100% renewable energy contract between Colbún and Minera Collahuasi for up to 650 GWh per year was announced. The contract period is from January 2024 to December 2035. The first phase (2024-2025) corresponds to an agreement for 230 GWh per year, and the second phase (2026-2035) covers 650 GWh per year, which will be supplied by both renewable assets already under construction and new projects to be built.

As of September 30, the Company has achieved 63% progress on the Horizonte wind project, reaching mechanical completion of 29 wind turbines by the end of the quarter. The construction of foundations has been completed, and work on internal roads and turbine platforms is still in progress, with an overall progress of 93% in civil works, substations, transmission lines, and medium voltage networks, as well as 78% progress in electrical works. In total, 407 main components have been unloaded at the wind turbine site. It's worth mentioning that the Company have experienced difficulties transporting oversized wind turbine components from Puerto Angamos in Mejillones to the Project site, due to the shortage of available police escorts for these transfers. During this quarter, there has been progress with the possibility to complement with private escorts on a "trial basis .

As of September 30, the Diego de Almagro power plant's battery storage system has conducted real-time signal testing (SITR), which was essential for its certification and commercial operation. Currently, it is performing daily energy charging and injection operations, but awaits approval from the National Electric Coordinator for commercial operation.

4

2.

2.

Table 1 shows a comparison between physical energy and capacity sales, and generation in 3Q22 and 3Q23, and cumulative as of Sep-22 and Sep-23.

Table 1: Physical sales and generation in Chile

Accumulated Figures	Sales	Quarterly Figures	Var %	Var %
Sep-22	Sep-23	3Q22	3Q23	Ac/Ac	Q/Q
9,950	9,995	Total Physical Sales (GWh)	3,211	3,189	0%	(1%)
1,829	1,962	Regulated Clients	658	684	7%	4%
7,116	7,002	Unregulated Clients	2,323	2,241	(2%)	(3%)
1,005	1,031	Sales to the Spot Market	231	264	3%	15%
1,548	1,625	Capacity Sales (MW)	1,548	1,625	5%	5%
Accumulated Figures	Generation	Quarterly Figures	Var %	Var %
Sep-22	Sep-23	3Q22	3Q23	Ac/Ac	Q/Q
10,118	10,197	Total Generation (GWh)	3,245	3,237	1%	(0%)
3,460	4,523	Hydraulic	1,654	2,428	31%	47%
5,986	5,134	Thermal	1,420	656	(14%)	(54%)
3,772	3,606	Gas	681	434	(4%)	(36%)
206	62	Diesel	23	1	(70%)	(98%)
2,008	1,466	Coal	717	221	(27%)	(69%)
673	539	VRE*	171	153	(20%)	(10%)
84	69	Wind Farm	27	28	(18%)	4%
589	470	Solar	144	126	(20%)	(13%)
36	16	Spot Market Purchases (GWh)	36	16	(55%)	(13%)
970	1,015	Sales - Purchases to the Spot Market (GWh)	195	248	5%	27%

(*): Includes energy purchased from Punta Palmeras wind farm owned by Acciona and Santa Isabel owned by Total Sun Power. VRE: Variable renewable energies

Physical sales during 3Q23 reached 3,189 GWh, decreasing by 1% compared to 3Q22, mainly due to lower physical sales to unregulated clients, primarily explained by reduced consumption among mining clients. This effect was partially offset by (1) increased sales in the spot market due to lower consumption by our unregulated clients during this quarter, and (2) increased in physical sales to regulated clients explained by the expiration of contracts between other generation companies and distribution companies, resulting in a higher load factor for the contracts still in force.

On the other hand, generation for the quarter reached 3,237 GWh, in line with 3Q22. This generation level was mainly due to increased hydroelectric generation (+773 GWh) due to better hydrology conditions, which offset a decrease in thermal generation (-764 GWh), particularly from coal (-496 GWh).

In cumulative terms, physical sales as of Sep-23 reached 9,995 GWh, in line with cumulative sales as of Sep-22, primarily due to a balance between increased sales to regulated clients and decreased sales to unregulated clients, given the reduced consumption among mining clients. Cumulative generation, on the other hand, reached 10,197 GWh as of Sep-23, increasing by 1% compared to Sep-22, mainly due to increased hydroelectric generation (+1,064 GWh). These effects were partially offset by decreased thermal generation (-852 GWh), as a result of reduced coal-based generation.

Spot market balance during the quarter recorded net sales of 248 GWh, compared to 195 GWh of net sales in 3Q22. This variation is mainly explained by the reduced consumption of unregulated clients mentioned earlier. In cumulative terms, as of Sep-23, the spot market balance registered net sales of 1,015 GWh, while as of Sep-22, net sales of 970 GWh were recorded. This variation is primarily explained by higher cumulative generation.

5

Commitments vs. Generation

16.000		GWh
14.000
12.000
10.000
8.000
6.000
4.000
2.000
0
3Q22	3Q23	3Q22	3Q23
		LTM	LTM

Commercial Commitments

Hydro Generation

VRE Generation

Thermal Generation Coal

Thermal Generation	Natural Gas
Thermal Generation	Diesel

Generation mix in Chile: As of Sep-23, the hydrological year (Apr23-Mar24) has presented variations in terms of rainfalls of an average year in the main SEN basins. In this way, the surpluses/deficits were Aconcagua: -15%; Maule: +46%; Laja: +52%; Biobío: +35%; Chapo: +6%. Average marginal cost, measured at Alto Jahuel, decreased 17% compared to 3Q22, averaging US$52.3/MWh in 3Q23.

Accumulated Figures				SEN Generation				Quarterly Figures	Var %	Var %
Sep-22	Sep-23							3Q22	3Q23	Ac/Ac	Q/Q
62,465	62,756			Total Generation (GWh)			20,846	21,142	0%	1%
13,296	15,907				Hydraulic					5,836	8,020	20%	37%
12,534	13,761					Gas					3,854	3,048	10%	(21%)
1,296		454					Diesel					228	39	(65%)	(83%)
16,580	11,346					Coal					4,693	3,381	(32%)	(28%)
6,709		7,217				Wind Farm				2,376	2,442	8%	3%
10,003	11,971					Solar					3,174	3,508	20%	11%
2,047		2,099					Others					684	702	3%	3%
					Alto Jahuel Marginal Costs
250						USD/MWh
200
150
100									82			2022
												2023
50
									48
0
	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec

6

2.2.

Table 2 shows a comparison between physical energy and capacity sales and generation in 3Q22 and 3Q23, and cumulative as of Sep-22 and Sep-23.

Table 2: Physical sales and generation in Peru

Accumulated Figures	Sales	Quarterly Figures	Var %	Var %
Sep-22	Sep-23	3Q22	3Q23	Ac/Ac	Q/Q
3,104	3,008	Total Physical Sales (GWh)	1,150	1,169	(3%)	2%
1,464	1,474	Regulated Clients	482	476	1%	(1%)
340	1,058	Unregulated Clients	116	338	-	-
1,300	476	Sales to the Spot Market	553	355	(63%)	(36%)
568	570	Capacity Sales (MW)	570	570	0%	(0%)
Accumulated Figures	Generation	Quarterly Figures	Var %	Var %
Sep-22	Sep-23	3Q22	3Q23	Ac/Ac	Q/Q
3,132	2,504	Total Generation (GWh)	1,176	1,197	(20%)	2%
3,132	2,504	Gas	1,176	1,197	(20%)	2%
44	567	Spot Market Purchases (GWh)	-	-	-	-
1,256	(91)	Sales - Purchases to the Spot Market (GWh)	553	355	-	(36%)

Physical sales during 3Q23 reached 1,169 GWh, increasing by 2% compared to 3Q22. The higher physical sales are primarily explained by increased sales to unregulated clients, due to the entry of new supply contracts. This effect was partially offset by lower spot market sales compared to 3Q22, mainly due to the increased commitments with the unregulated clients mentioned before.

Fenix s generation reached 1,197 GWh, increasing by 2% compared to 3Q22. This higher generation is mainly explained because during 3Q22, there was forced unavailability of the plant due to turbine failures, which meant that CT Fenix was approximately 20 hours out of service during the months of July and August in 3Q22.

In cumulative terms, physical sales as of Sep-23 reached 3,008 GWh, decreasing by 3% compared to Sep-22, primarily due to lower spot market sales. Furthermore, cumulative generation as of Sep-23 reached 2,504 GWh, decreasing by 20% compared to Sep-22, mainly due to the extended major maintenance, that lasted longer than the one conducted in the previous year.

The spot market balance in 3Q23 registered net sales of 355 GWh, compared to net sales of 553 GWh during 3Q22, due to increased consumption by unregulated clients resulting from the entry of new supply contracts mentioned earlier. In cumulative terms, as of Sep-23, net purchases of 91 GWh were recorded, compared to net sales of 1,256 GWh recorded as of Sep-22; the variations are mainly explained by the reduced availability of CT Fenix during this year.

Generation mix in Peru: The Mantaro river basin, which supplies the main hydroelectric complex in Peru, CH Mantaro and CH Restitución (900 MW), presented a hydrological condition with an 81.9% probability of exceedance as of September 2023, compared to 35.9% in September 2022.

In cumulative terms, hydroelectric generation in the National Interconnected Electric System (SEIN) decreased by 10.2% compared to Sep-22, primarily due to lower hydrology and maintenance of the Mantaro, Restitución, Cerro del Águila hydroelectric plants, and the shutdown of the Chaglla and Quitaracsa hydroelectric plants. On the other hand, thermoelectric generation increased by 25.4% as of Sep-23 compared to Sep-22, mainly due to increased system demand and reduced hydroelectric production, due to lower hydrology and the maintenance and shutdown of the hydroelectric plants.

The electricity demand growth rate at the end of 3Q23 was 3.1% compared to 3Q22, driven by increased consumption from mining companies.

7

Table 3 presents a summary of the Consolidated Income Statement (Chile and Peru) in 3Q22 and 3Q23, and cumulative as of Sep-22 and Sep-23.

Table 3: Income Statement (US$ million)

Accumulated Figures		Quarterly Figures		Var %	Var %
Sep-22	Sep-23		3Q22	3Q23		Ac/Ac	Q/Q
1.419,0	1.594,4	OPERATING INCOME	488,2	493,8		12%	1%
339,0	386,8	Regulated Customers Sales	123,2	134,7	14%	9%
729,8	864,1	Unregulated Customers Sales	249,2	260,5	18%	5%
316,0	285,8	Energy and Capacity Sales	104,6	74,2	(10%)	(29%)
34,2	57,7	Other Operating Income	11,3	24,3		69%	-

(812,8)	(922,1)	RAW MATERIALS AND CONSUMABLES USED	(248,6)	(228,5)		13%	(8%)
(105,1)	(110,9)	Transmission Tolls	(31,6)	(30,5)	5%	(3%)
(106,1)	(172,1)	Energy and Capacity Purchases	(37,3)	(66,2)	62%	77%
(384,9)	(419,8)	Gas Consumption	(115,3)	(77,2)	9%	(33%)
(65,1)	(20,4)	Diesel Consumption	(7,2)	(4,3)	(69%)	(41%)
(104,6)	(123,7)	Coal Consumption	(41,6)	(22,3)	18%	(46%)
(47,0)	(75,4)	Other Operating Expenses	(15,6)	(27,9)		60%	79%

606,2	672,3		GROSS PROFIT	239,6	265,3	11%	11%
(62,2)	(69,4)		Personnel Expenses	(20,7)	(23,8)	12%	15%
(40,4)	(49,8)		Other Expenses, by Nature	(13,7)	(15,3)	23%	12%
(162,1)	(150,8)		Depreciation and Amortization Expenses	(54,0)	(49,9)	(7%)	(8%)
341,5	402,3		OPERATING INCOME (LOSS) (*)	151,1	176,3	18%	17%
503,6	553,1		EBITDA	205,2	226,2	10%	10%
14,1	49,4		Financial Income	7,4	17,6	-	-
(64,3)	(66,2)		Financial Expenses	(22,8)	(21,0)	3%	(8%)
(12,9)	(6,1)		Exchange rate Differences	(3,5)	(4,0)	(53%)	15%
8,4	10,2		Profit (Loss) of Companies Accounted for Using the Equity Method	3,2	2,8	21%	(12%)
(50,8)	81,6		Other Profit (Loss)	(18,5)	4,1	-	-
(105,5)	68,9		NON-OPERATING INCOME	(34,2)	(0,5)	-	(99%)
236,0	471,3		PRE-TAX PROFIT (LOSS)	117,0	175,8	-	50%
(61,7)	(123,7)		Income Tax Expense	(36,3)	(51,4)	-	42%
174,3	347,6		AFTER TAX PROFIT (LOSS)	80,7	124,4	99%	54%
167,0	339,6		PROFIT (LOSS) OF CONTROLLER	80,6	117,7		-	46%
7,2	8,0		PROFIT (LOSS) ATTRIBUTABLE TO MINORITY INTEREST	0,1	6,7	11%	-

(*): The subtotal sho			inancial Statements. This is explained
by a change in taxonomy dictated by the CMF (Fi			are only non-operating
items, was incorporated as an operating item in the Financial Statements.
Table 4: Closing Exchange Rates
Exchange Rates	Sep-22	Dec-22	Sep-23
Chile (CLP / US$)	932.08	855.86	895.60
Chile UF (CLP/UF)	33,086.83	35,110.98	36,134.97
Peru (PEN / US$)	3.83	3.82	3.80

8

3.1. Chile's Operating Income Analysis

Table 5 presents a summary of Operating Income and EBITDA in 3Q22 and 3Q23, and cumulative as of Sep-22 and Sep-23. Subsequently, the major accounts and/or variations will be analyzed.

Table 5: EBITDA Chile (US$ million)

Accumulated Figures		Quarterly Figures		Var %
Sep-22	Sep-23		3Q22	3Q23	Ac/Ac	Q/Q
1,251.7	1,344.6	OPERATING INCOME	429.0	367.2	7%	(14%)
230.9	268.0	Regulated Customers Sales	87.1	96.6	16%	11%
715.4	792.5	Unregulated Customers Sales	244.4	224.0	11%	(8%)
278.4	233.9	Energy and Capacity Sales	87.6	24.2	(16%)	(72%)
27.0	50.2	Other Operating Income	10.0	22.4	86%	-
(728.8)	(760.2)	RAW MATERIALS AND CONSUMABLES USED	(218.1)	(155.8)	4%	(29%)
(100.7)	(107.5)	Transmission Tolls	(30.3)	(29.0)	7%	(4%)
(102.7)	(99.6)	Energy and Capacity Purchases	(36.1)	(33.4)	(3%)	(7%)
(315.3)	(352.5)	Gas Consumption	(89.8)	(50.6)	12%	(44%)
(65.0)	(17.0)	Diesel Consumption	(7.2)	(0.9)	(74%)	(87%)
(104.6)	(123.7)	Coal Consumption	(41.6)	(22.3)	18%	(46%)
(40.5)	(59.9)	Other Operating Expenses	(13.1)	(19.6)	48%	50%
522.9	584.4	GROSS PROFIT	210.9	211.4	12%	0%
(56.1)	(61.9)	Personnel Expenses	(18.9)	(21.1)	10%	11%
(34.8)	(43.8)	Other Expenses, by Nature	(11.6)	(13.1)	26%	13%
(135.5)	(125.1)	Depreciation and Amortization Expenses	(45.1)	(41.6)	(8%)	(8%)
296.5	353.7	OPERATING INCOME (LOSS) (*)	135.2	135.5	19%	0%
432.0	478.7	EBITDA	180.4	177.2	11%	(2%)

inancial Statements. This is explained

f Colbún are only non-operating items, was incorporated as an operating item in the Financial Statements.

Operating income in 3Q23 amounted to US$367.2 million, decreasing by 14% compared to the operating income of US$429.0 million recorded in 3Q22, mainly due to (1) lower sales in the spot market, explained by a reduction in the average selling price, and (2) lower sales to unregulated clients associated with a decreased in physical sales to mining clients and a lower average price due to a drop in fuel prices compared to 3Q22. These effects were partially offset by higher sales to regulated clients, mainly associated with a higher average selling price due to a positive variation in the indexers during the quarter and an increase in the load factor for contracts that are still active due to the expiration of contracts from other companies in the market. In cumulative terms, operating income as of Sep-23 amounted to US$1,344.6 million, increasing by 7% compared to Sep-22, mainly due to higher sales to unregulated and regulated clients, despite the decrease in volume, driven by an increased average sale price. This effect is partially offset by lower sales in the spot market for the same reasons on a quarterly basis.

Raw materials and consumables used costs in 3Q23 totaled US$155.8 million, decreasing by 29% compared to 3Q22, mainly due to lower gas and coal consumption costs associated with reduced generation from both fuels, which, in turn, is explained by the increase in hydroelectric generation during the quarter. In cumulative terms, raw materials and consumables used costs as of Sep-23 reached US$760.2 million, increasing by 4% compared to Sep-22, mainly due to higher gas and coal consumption costs due to an increase in the price of these fuels. These effects are partially offset by lower diesel consumption costs, associated with reduced generation from this fuel during the year.

EBITDA in 3Q23 reached US$177.2 million, decreasing by 2% compared to the EBITDA of US$180.4 million in 3Q22, mainly due to lower operating income, partially offset by lower raw materials and fuel costs mentioned above. In cumulative terms, EBITDA as of Sep-23 totaled US$478.7 million, increasing by 11% compared to Sep-22, mainly due to higher operating income, partially offset by higher raw materials and fuel costs.

9

3.2. Peru's Operating Income Analysis

Table 6 shows a summary of Fenix's Operating Income and EBITDA for the quarters 3Q22 and 3Q23, and cumulative as of Sep- 22 and Sep-23. Subsequently, the main accounts and/or variations will be analyzed.

Table 6: EBITDA Peru (US$ million)

Accumulated Figures		Quarterly Figures		Var %
Sep-22	Sep-23		3Q22	3Q23	Ac/Ac	Q/Q
167.3	249.8	OPERATING INCOME	59.2	126.6	49%	-
108.1	118.8	Regulated Customers Sales	36.1	38.1	10%	6%
14.5	71.6	Unregulated Customers Sales	4.8	36.5	-	-
37.6	51.9	Energy and Capacity Sales	17.0	50.1	38%	-
7.2	7.5	Other Operating Income	1.3	1.9	4%	47%
(84.1)	(161.9)	RAW MATERIALS AND CONSUMABLES USED	(30.6)	(72.6)	92%	-
(4.5)	(3.4)	Transmission Tolls	(1.3)	(1.5)	(25%)	16%
(3.4)	(72.5)	Energy and Capacity Purchases	(1.3)	(32.8)	-	-
(69.5)	(67.3)	Gas Consumption	(25.5)	(26.6)	(3%)	4%
(0.1)	(3.4)	Diesel Consumption	0.0	(3.4)	-	-
(6.7)	(15.4)	Other Operating Expenses	(2.5)	(8.3)	-	-
83.1	87.9	GROSS PROFIT	28.6	53.9	6%	89%
(6.1)	(7.5)	Personnel Expenses	(1.8)	(2.7)	23%	51%
(5.7)	(6.3)	Other Expenses, by Nature	(2.0)	(2.3)	11%	14%
(26.6)	(25.7)	Depreciation and Amortization Expenses	(8.9)	(8.2)	(3%)	(7%)
44.8	48.3	OPERATING INCOME (LOSS) (*)	15.9	40.6	8%	-
71.4	74.1	EBITDA	24.7	48.9	4%	98%

s) from operating activitie	ine presented in the Financial Statements. This is explained
by a change in taxonomy dictated by the CMF (Financial Market Commission), by means of which	-operating
items, was incorporated as an operating item in the Financial Statements.

Operating income in 3Q23 amounted to US$126.6 million, increasing compared to the income of US$59.2 million recorded in 3Q22, mainly due to (1) higher sales in the spot market resulting from an increase in the average selling price, and (2) higher sales to unregulated clients due to the entry into force of new contracts. In cumulative terms, operating income as of Sep-23reached US$249.8 million, increasing by 49% compared to Sep-22,primarily due to the same reasons that explain the variations on a quarterly basis.

Raw materials and consumables used costs in 3Q23 reached US$72.6 million, increasing compared to 3Q22, mainly due to higher purchases of energy and capacity in the spot market, mostly driven by the increase in the average purchase price. In cumulative terms, raw materials and consumables used costs as of Sep-23 reached US$161.9 million, increasing by 92% compared to Sep-22, primarily due to higher purchases of energy and capacity in the spot market resulting from the increase in the average purchase price and the higher volume of purchases due to the extended maintenance of Fenix during this year.

Fenix's EBITDA totaled US$48.9 million in 3Q23, recording a 98% increase compared to the EBITDA of US$24.7 million recorded in 3Q22, primarily due to higher sales of energy and capacity in the spot market as a result of the previously mentioned higher average selling price. In cumulative terms, EBITDA as of Sep-23 reached US$74.1 million, increasing by 4% compared to Sep-22, primarily explained by the same reasons that account for the variations on a quarterly basis.

10