ACEA S p A : Interim Report on Operations as at 31 March 2024

	Interim Report on Operaons
	as at 31 March 2024
Table of Contents
Report on Operaons
Corporate bodies	3
Financial Highlights	4
ACEA Organisaonal Model	5
Summary of operaons and income, equity and financial performance of the Group	7
Summary of Results	8
Summary of Results: economic performance	9
Summary of results: trends in financial posion and cash flows	12
Net financial debt	16
Reference context	17
Operang Segments	18
Trend of Operang segments	18
Significant events during the period and a6erwards	27
Business outlook	28
Consolidated Financial Statements
Form and Structure	29
Accounng standards and measurement criteria	30
Scope of consolidaon	31
Applicaon of the IFRS 5 standard	34
Consolidated Income Statement	35
Consolidated Statement of Comprehensive Income	36
Consolidated Statement of Financial Posion	37
Consolidated Cash Flow Statement	38
Consolidated Statement of Changes in Shareholders' equity	39
Declaraon by the Manager Appointed to Prepare the Company Accounng Documents in accordance with the provisions of Arcle
154-bis, paragraph 2 of Italian Legislave Decree no. 58/1998	40

Interim Report on Operaons as at 31 March 2024

Corporate bodies

Board of Directors
Barbara Marinali	Chairperson
Fabrizio Palermo	Chief Execuve Officer
Antonella Rosa Bianchessi	Director
Alessandro Caltagirone	Director
Massimiliano Capece Minutolo Del Sasso	Director
Antonino Cusimano	Director
Francesca Menabuoni	Director
ElisabeAa Maggini	Director
Luisa Melara	Director
Angelo Piazza	Director
Alessandro Picardi	Director
Vincenza Patrizia Rugliano	Director
Nathalie Tocci	Director
Yves Rannou*	Director
Board of Statutory Auditors
Maurizio Lauri	Chairperson
Claudia Capuano	Standing Auditor
Leonardo Quagliata	Standing Auditor
Rosina Cichello	Alternate Auditor
Vito Di BaFsta	Alternate Auditor
Execuve Responsible
Sabrina Di Bartolomeo

* appointed by the Shareholders' Meeng on 12 April 2024

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Interim Report on Operaons as at 31 March 2024

Financial Highlights

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Interim Report on Operaons as at 31 March 2024

ACEA Organisaonal Model

51,00% Roma Capitale

20,22% Market

23,33% Suez

5,45% Caltagirone

The above chart only shows equity investments of more than 3%, as confirmed by CONSOB data

Acea is one of the leading Italian industrial groups and has been listed on the stock exchange since 1999. The Group has adopted an organisational structure and operating model that supports its strategic guidelines, founded on growth in the water market through infrastructure development, geographic expansion, strategic partnerships, strengthening technology and protecting water resources; the resilience of the electricity network and quality of service in the city of Rome; developing new renewable capacity to help face the energy transition; a push towards the circular economy with geographic expansion, also in synergy with other businesses. The macro sectors in which ACEA works are broken down into the industrial segments listed below:

The Acea Group is the top Italian operator in the water sector serving 10 million people: it manages the integrated water service in Rome and Frosinone and in the relative provinces, as well as in other areas of Lazio, in Tuscany, Umbria, Campania and Molise. The Group is also in Abruzzo, Molise and Campania, as it has entered the methane distribution market in the Municipality of Pescara, the Province of L'Aquila, the Provinces of Campobasso and Isernia and the Province of Salerno. Finally, the area also includes the ASM Terni Group, which is active not only in the water sector, but also in waste collection and disposal and electricity distribution. The Group operates across the entire value chain, from water collection and distribution to its purification and reuse.

The area also includes the companies that manage water activities in Latin America and its objective is to make the most of development opportunities in other businesses related to those already held in Italy. It has a strong presence in Honduras and Peru, reaching a population of approximately 10 million. The activities are carried out in partnership with local and international partners, including through staff training and the transfer of know-how to local entrepreneurs.

The Acea Group is one of the main national operators, distributing about 9 TWh of electricity and managing 1.7 million PODs in the Rome area. Additionally, the Group manages public and artistic lighting in the Capital with over 250 thousand lighting points. The ACEA Group is involved in energy efficiency projects and the development of new technologies, including network partitioning for dynamic management, 2G smart meter control over PODs, and extensive demand response via AI and IoT platform, additionally, the Group is developing smart public lighting projects.

The Acea Group is one of the leading national players with around 1.8 million tonnes of waste processed each year, including those handled. The Group operates throughout the entire waste treatment chain, primarily focusing on segments with higher margins. Among the various treatment and disposal plants operated in eight regions there is the main waste-to-energy plant and the largest anaerobic digestion and composting plant in the Lazio Region and the largest mechanical/biological treatment plant in the Abruzzo Region. The Group focuses on developing business investments in waste to energy and waste to recycling, areas considered to have high potential. It also invests in waste recovery and recycling in the plastic, paper, and metal sectors, as well as in producing high- quality compost. This aligns with the strategic objective of consolidating its presence in the entire cycle by maximising circularity and focusing on reusing resources.

The Acea Group is one of the leading Italian players in the sale of electricity and offers innovative and flexible solutions for the supply of electricity and natural gas with the objective of consolidating its positioning as a dual fuel operator. It operates on the market segments of medium-sized enterprises and households to improve the quality of the services offered with particular regard to web and social channels. It supervises the Group's energy management policies.

The Acea Group is one of the main national operators in the field of generation from renewable sources (hydroelectric and photovoltaic) and is engaged in energy efficiency and energy solution projects in the business segment, particularly focused on finding innovative approaches in the management of production asset and the implementation of new production capacity that sustains

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Interim Report on Operaons as at 31 March 2024

internal consumption and reduces the Group's carbon footprint, decreasing CO2 emissions to meet SBTi targets. In this regard, the Group aims to capitalise on opportunities for developing solar pipelines, including through partnerships with financial institutions.

The Acea Group is a specialised centre of excellence renowned for its cutting-edgeknow how in designing, constructing, and managing integrated water systems: from sourcing springs to managing aqueducts, distribution networks, sewage systems, and purification facilities. It develops applied research projects aimed at technological innovation in the water, environmental and energy sectors. Laboratory and engineering consultancy services are of particular importance. The Acea Group is also engaged in the design and creation of plants for the environment and for the treatment of water and waste.

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Interim Report on Operaons as at 31 March 2024

Summary of operaons and income, equity and financial performance of the Group

Definion of alternave performance measures

On 5 October 2015, ESMA (European Securities and Markets Authority) published its guidelines (ESMA/2015/1415) on criteria for the presentation of alternative performance measures which replace, as of 3 July 2016, the CESR/05-178b recommendations. These guidelines were transposed into our system with CONSOB Communication no. 0092543 dated 3 December 2015. In addition, on 4 March 2021 ESMA published the guidelines on the disclosure requirements deriving from the new Prospectus Regulation (Regulation EU 2017/1129 and Delegated Regulations EU 2019/980 and 2019/979), which update the previous CESR Recommendations (ESMA/2013/319, in the revised version of 20 March 2013). Starting from 5 May 2021, on the basis of CONSOB Call for Attention No. 5/21, the aforementioned ESMA Guidelines also replace the CESR Recommendation on debt. Therefore, under the new provisions, listed issuers will have to present, in the explanatory notes to their annual and semi-annual financial statements published from 5 May 2021 onwards, a new statement on debt to be drafted in accordance with the instructions in paragraphs 175 and following of the above ESMA Guidelines.

The content and meaning of the non-GAAP measures of performance and other alternave performance indicators used in these financial statements are illustrated below:

For the Acea Group, the EBITDA is an operating performance indicator and from 1 January 2014 also includes the condensed result of equity investments in jointly-controlled entities for which the consolidation method changed when the international accounting standards IFRS 10 and IFRS 11 came into force. EBITDA is determined by adding Operating profit/loss (EBIT) to "Amortisation, depreciation, provisions and impairment", insofar as these are the main non-cash items;

financial debt is represented and determined in accordance with what is indicated in the aforementioned ESMA guidelines and in particular in paragraph 127 of the recommendations contained in document no. 319 of 2013, implementing Regulation (EC) 809/2004. This indicator is determined as the sum of short-term borrowings ("Short-term loans", "Current part of long-term loans" and "Current financial liabilities") and long-term borrowings ("Long-term loans") and the related derivative instruments ("Non-current financial liabilities"), net of "Cash and cash equivalents" and "Current financial assets";

the net financial position is an indicator of the ACEA Group's financial structure determined in continuation with previous years and used, as from this document, exclusively for information presented in the business areas in order to provide clear segment information that can be easily reconciled with the financial debt (ESMA) referred to above. This indicator is obtained from the sum of Non-current borrowings and Financial liabilities net of non-current financial assets (financial receivables and securities other than equity investments), Current financial payables and other Current financial liabilities net of current financial assets and Cash and cash equivalents;

net invested capital is the sum of "Current assets", "Non-current assets" and Assets and Liabilities held for sale, less "Current liabilities" and "Non-current liabilities", excluding items taken into account when calculating the net financial position;

net working capital is the sum of Current receivables, Inventories, the net balance of other current assets and liabilities and Current payables, excluding the items considered in calculating the net financial position.

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Interim Report on Operaons as at 31 March 2024

Summary of Results

	Income statement data (€ million)	31/03/2024		31/03/2023		Change	% Change
	Consolidated Net Revenue		1,026.3		1,239.9	(213.6)	(17.2%)
	Consolidated Operang Costs		672.1		910.2	(238.2)	(26.2%)
	Net Income/(Expense) from commodity risk		0.0		0.0		0.0		n.s.
	management
	Profit / (loss) from non-financial equity investments		2.7		6.3		(3.6)		(56.8%)
	EBITDA		356.9		335.9	21.0	6.3%
	Operang profit/(loss)		168.3		149.8	18.5	12.3%
	Net profit/(loss)		93.5		81.4	12.1	14.8%
	Profit/(Loss) due to third pares		10.9		8.8		2.1		23.6%
	Net profit/(loss) aAributable to the Group		82.6		72.6		10.0		13.7%

	Financial posion data	31/03/2024			31/12/2023			Change	% Change	31/03/2023			Change		% Change
	(€ million)
	Net Invested Capital				7,834.2		7,669.8			164.3	2.1%		7,191.6			642.5	8.9%
	Net Financial Debt				(4,913.2)		(4,846.8)			(66.4)		1.4%		(4,338.6)		(574.6)	13.2%
	Consolidated Shareholders'			(2,921.0)			(2,823.1)			(97.9)		3.5%				(2,853.1)			(68.0)		2.4%
	Equity
	EBITDA (€ million)					31/03/2024			31/03/2023				Change	% Change
	Environment					13.9			20.8			(6.9)		(33.1%)
	Commercial					43.4			32.8			10.5		32.1%
	Water (Overseas)					9.2			9.6			(0.4)		(4.0%)
	Water					185.5			174.7			10.8		6.2%
	Network and public lighng					104.4			92.4			12.0		13.0%
	Producon					7.9			13.6			(5.8)		(42.3%)
	Engineering & Infrastructure Projects				1.8			0.9			0.9		99.1%
	Corporate					(9.1)			(9.0)			(0.1)		1.3%
	Total EBITDA					356.9			335.9			21.0		6.3%
	Investments (€ million)					31/03/2024			31/03/2023				Change	% Change
	Environment					10.3			7.6			2.7		35.5%
	Commercial					15.6			12.5			3.1		24.7%
	Water (Overseas)					1.2			0.8			0.4		50.8%
	Water					155.1			161.5			(6.4)		(4.0%)
	Network and public lighng					56.8			64.5			(7.7)		(12.0%)
	Producon					5.0			4.4			0.6		13.8%
	Engineering & Infrastructure Projects				0.7			1.0			(0.3)		(31.4%)
	Corporate					2.8			5.8			(3.0)		(52.3%)
	Total Investments					247.5			258.2			(10.7)		(4.1%)

* The value of investments is inclusive of financed investments amounng to € 5.1 million for 2023 and € 11.4 million for 2022.

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Interim Report on Operaons as at 31 March 2024

Summary of Results: economic performance

Income statement data (€ million)	31/03/2024		31/03/2023	Change	% Change
Revenue from sales and services		1,003.3		1,216.0	(212.7)	(17.5%)
Other revenue and income		23.0		23.9	(0.8)	(3.4%)
Costs of materials and overhead		582.6		823.3	(240.7)	(29.2%)
Staff costs		89.4		86.9	2.5	2.9%
Net Income/(Expense) from commodity risk		0.0		0.0	0.0	n.s.
management
Profit / (loss) from non-financial equity investments		2.7		6.3	(3.6)	(56.8%)

	EBITDA		356.9		335.9	21.0	6.3%
	Amorsaon, depreciaon, provisions and		188.7		186.1	2.6		1.4%
	impairment charges
	Operang profit/(loss)		168.3		149.8	18.5	12.3%
	Financial operaons		(33.0)		(33.7)	0.7		(1.9%)
	Equity investments		0.4		0.2	0.2		89.6%
	Profit/(loss) before tax		135.7		116.3	19.3	16.6%
	Income tax		42.2		34.9	7.3		20.9%
	Net profit/(loss)		93.5		81.4	12.1	14.8%
	Profit/(Loss) due to third pares		10.9		8.8	2.1		23.6%
	Net profit/(loss) aAributable to the Group		82.6		72.6	10.0		13.7%

It should be noted that the financial results as at 31 March 2024 do not indicate any changes in the scope of consolidation.

As at 31 March 2024, revenue from sales and servicesamounted to € 1,003.3 million, a decrease of € 212.7 million (- 17.5%) compared to the same period of the previous year. The decrease is mainly attributable to lower revenues:

from electricity sales and services, (- € 188.0 million) attributed to lower unit prices in the first quarter of 2024 (PUN change - 42%), alongside a decrease in quantities sold;

from sustainable development (-€ 21.0 million) arising from the sale, installation and customer support of activities and services in the area of energy efficiency, smart services and smart comp projects as a result of the conclusion of the"superbonus", projects that were initiated and completed in the previous year;

from services to customers (-€ 16.8 million) resulting in part from the negative change in inventories related to multi-year job orders (-€ 10.2 million) and from lower revenues realised in connection with the public lighting contract of the Municipality of Rome (-€ 4.1 million) as a result of lower activities;

from waste transfer and landfill management (- € 6.9 million) attributable to lower revenues from street sweeping and collection of ASM Terni (- € 4.6 million); this decrease was primarily a result of the transfer of invoicing activities in 2024 from the municipalities managed by CNS - Cosp Tecno Service to the latter. Furthermore, there were lower revenues from biomass transfer amounting to - € 1.9 million.

This was offset by higher revenues from gas sales (+ € 15.5 million) and higher revenues from electricity incentives (+ € 3.7 million).

Other revenuedecreased by € 0.8 million (- 3.4%) compared to the same period last year. The change resulted mainly from the offsetting impact of lower claims and penalties (- € 1.8 million) and higher IFRIC 12 margin revenues (+ € 1.1 million) attributed to higher investments.

External costsdecreased overall by € 240.7 million (- 29.2%) compared to 31 March 2023. The change is mainly due to the reduction in costs related to the procurement of electricity and gas on the free market and on the gradually protected market (-€ 193.7 million), which is in line with the revenue figures. Also contributing to the change were lower costs i) for services and tenders (- € 38.2 million), mostly attributable to energy efficiency and smart services projects (- € 20.6 million), ASM Terni's collection and sweeping service (- €

4.1 million), in line with the change in revenues, and, residually, lower costs for electricity consumption (- € 9.8 million); ii) for materials (- € 9.4 million), mainly related to the change in SIMAM inventories.

Labour costsincreased by € 2.5 million (+ 2.9%) compared to the same period of the previous year, primarily due to the increase in average costs, partially offset by a reduction in personnel. The average number of employees stood at 9,524, down by 958 compared to the same period last year, mainly as a result of the end of the three-year contract for the management of the Lima drinking water pumping stations operated by Consorcio Acea (- 655 employees).

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Interim Report on Operaons as at 31 March 2024

€ million	31/03/2024	31/03/2023	Change		% Change
Personnel costs including capitalised costs	140.3	139.6		0.7	0.5%
Costs capitalised	(50.9)	(52.7)		1.9	(3.5%)
Staff costs		89.4	86.9		2.5	2.9%

The net income/(expense) from commodity risk managementshows a net balance. The previous year it included net income on hedging derivatives closed in the period, in line with IFRS 9.

Income from equity investments of a non-financialnaturerepresents the consolidated result according to the equity method included among the components forming the consolidated EBITDA of the strategic companies.

€ million	31/03/2024		31/03/2023			Change			% Change
EBITDA		38.9			37.3		1.5	4.1%
Amorsaon, depreciaon, provisions and		31.2			26.6			4.6		17.2%
impairment charges
Financial operaons		(3.0)			(2.1)			(0.9)		45.5%
Equity investments		0.0			0.0			0.0		n.s.
Income tax		1.9			2.4			(0.5)		(19.2%)
Income from equity investments of a non-financial		2.7			6.3			(3.6)		(56.8%)
nature

Income from equity investments for these companies fell by € 3.6 million, mainly due to greater amortisation/depreciation related to the growth of investments.

EBITDA rose from € 335.9 million at 31 March 2023 to € 356.9 million at 31 March 2024, recording an increase of € 21.0 million or 6.3%. EBIDTA net of non-recurring items due to the shutdown of the Terni WTE smoke line for reimbursement (€ 3.0 million) increased by 7.2% (+€ 24.1 million). The change is therefore due to the following offsetting factors:

higher margins resulted from the rise in water tariff revenues related to non-pass-through items (+€ 14.5 million), driven by the increasing level of investments. However, this was partly offset by the decreased results of the equity consolidated water companies (- € 3.6 million) attributed to higher depreciation and amortisation resulting from investment growth;

higher margins from energy balancing (+€ 16.6 million) partly offset by lower capitalised personnel (-€ 2.6 million), lower revenues from connection fees and compensation (-€ 1.1 million), and from the management of the public lighting service in the Municipality of Rome (-€ 0.8 million) as a result of lower activities;

an increase in the margin on electricity and gas sales on the free market (+€ 7.9 million and + € 4.0 million, respectively), in the margin on the Gradual Protection Service (+ € 1.6 million), and in the margin deriving from energy management activities (+ € 6.8 million), only partly offset by the reduction in the energy margin on the protected market (- € 4.5 million) and by the higher operating costs incurred (€ 1.7 million);

lower margins one-mobility,smart services and smart comp activities (- € 3.8 million);

lower margins from hydroelectrical production (- € 6.0 million), mainly impacted by the price effect (- € 62/MWh and partially offset by lower quantities (- 36.6 GWh);

decreased margins in waste-to-energy (WTE) were partially due to the energy scenario, particularly affecting the San Vittore plant (- € 2.5 million), and the halt of the Terni WTE flue gas line for refurbishment (- € 3.0 million). Additionally, performance worsened in recycling (- € 1.0 million), and there were reduced volumes of liquids treated (- € 0.5 million), partly offset by increased deliveries to TMB-Dump (+ € 0.9 million).

EBITamounted to € 168,3 million and increased by € 18.5 million compared to the same period of the previous year. Below are details of the items influencing EBIT.

€ million	31/03/2024		31/03/2023		Change			% Change
Depreciaon/amorsaon and impairment losses		167.2		159.0			8.2	5.2%
Net write-downs(write-backs) of trade receivables		19.7		23.4			(3.6)	(15.6%)
Provisions and releases for risks and charges		1.7		3.7			(2.1)	(54.9%)
Amorsaon, depreciaon, impairment and		188.7			186.1			2.6		1.4%
provisions

The increase in amortisation and impairment(+ € 8.2 million) is mainly linked to natural growth in amortisation from regulated activities, for the most part in the "Water" and "Networks and Public Lighting" segment, as a result of the higher investments made in previous years, the entry into service of assets under construction, and partly due to the increase in amortisation and depreciation related to commissioning costs for the acquisition of new Acea Energia customers (+ € 1.0 million).

Net write-downs (write-backs)of trade receivablesdecreased compared to the same period of the previous year (-€ 3.6 million). This result is primarily attributed, alongside the robust collection performance of the main Group companies, to the decline in sales volumes

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