Based on the provided financial statements, industry criteria, and market data, here is an assessment of the extent to which Acea S.p.A. should issue hybrid bonds.

**1. Industry and Business Risk Profile**
Acea is an Italian multi-utility with core operations in water, electricity distribution, and waste management. Based on the S&P criteria for Regulated Utilities, Acea operates in a regulated environment. While the specific Italian regulatory framework's assessment (Strong, Adequate, etc.) is not provided, Italian energy and water regulation has historically been considered transparent and supportive, though subject to political influence.
Given its essential service monopoly status, Acea would be assessed under the Regulated Utilities framework. Its business risk profile is likely supported by the essential nature of its services, though tempered by sovereign and macroeconomic risks in Italy.

**2. Financial Metrics and Credit Profile**
We can calculate key metrics and compare them to the "Medial Volatility" table typically used for European regulated utilities with a regulatory advantage of at least adequate and country risk of '4' or better (Italy is generally '4').

*   **Capital Structure:** As of December 31, 2022, Equity was €2,755m, and adjusted total assets were €11,339m. Non-current financial liabilities were €4,722m and current financial liabilities were €619m, totaling €5,341m in gross financial debt. Cash was €560m. Net debt is roughly €4,781m.
*   **Leverage:** Net Debt / Equity is approximately 1.7x. More importantly, FFO to Net Debt is a core metric.
    *   Cash Flow from Operations (CFFO) before working capital was €1,062m.
    *   Adjustments for a regulated utility are necessary, but a rough proxy for FFO (Funds From Operations) can be derived. Using Operating Profit before interest and taxes + Depreciation + provisions = €566m + €595m + €68m = approx. €1,229m. Less taxes paid (€178m) and other non-cash items, a reasonable FFO is around €950m - €1,050m.
    *   FFO / Net Debt ≈ €1,000m / €4,781m ≈ 20% - 22%.
*   **Profitability and Coverage:** EBITDA was €1,277m (Revenue - External Costs - Employee Benefit). Finance Costs were €112m. EBITDA interest coverage is over 11x.

These metrics suggest a solid investment-grade profile, likely in the 'BBB+' or 'A-' range. The company is generating strong cash flow, has manageable leverage, and high interest coverage.

**3. Funding Needs and Capital Spending**
Capital expenditure is very high. Purchase of tangible and intangible assets totalled €1,050m (€350m + €700m). This significantly exceeds the CFFO from operations before capex. This high capex is a key driver for potential hybrid issuance to fund growth without leveraging the balance sheet. The company is investing heavily for growth, likely in energy transition and infrastructure upgrades.

**4. Market Conditions for Hybrid Issuance**
The swap curve data shows that rates in 2022 increased dramatically compared to 2020 and 2021.
*   Average 7Y Swap: -0.137% (2021) to 1.806% (2022).
*   Sub-senior delta (proxy for hybrid credit spread) for IG non-financials: ~2.3% in 2022.
This implies a total cost for a new deeply subordinated hybrid bond in 2022 of roughly 4% - 4.5% (1.8% base + 2.3% spread + new issue premium), which is a material increase from the near-zero rate environment of the prior years.
Acea's average cost of debt can be approximated by Finance Costs / Average Gross Debt = €112m / ~€5,200m ≈ 2.15%.
A new hybrid would materially increase the current cost of debt.

**5. Assessment against Guidelines**

*   **"No current hybrid in the capital structure" / "First year of hybrid bond issuance: never"**: The facts state Acea has never issued a hybrid bond. The guidance notes this is a "reliable signal that it has reasons not to do so either in the future."
*   **Leverage and Rating Headroom**: The company's FFO/Net Debt of >20% provides substantial headroom at a 'BBB+'/'A-' rating level. The company is not under "significant leverage pressure" or facing "material downgrade risk without hybrid support."
*   **Rationale for Issuance**: High capex intensity is a valid reason. However, the company's current strong cash flow generation sufficiently covers its increasing leverage from net debt growth.
*   **Cost of Hybrid vs. Cost of Debt**: The estimated cost of a hybrid (4-4.5%) would materially increase the current implied cost of debt (2.15%).

**Conclusion**
While Acea has high capex needs that could justify some capital structure optimization, the company has a strong investment-grade credit profile, significant FFO to debt headroom, and no established precedent for hybrid issuance. The cost of a new hybrid would be punitive relative to its current cost of senior debt. The most powerful indicator, as per the instructions, is the entity's historical behavior: it has *never* issued a hybrid, strongly suggesting management is averse to this instrument.

Given the strong standalone metrics, lack of rating pressure, unwillingness to issue in the past, and the materially higher cost compared to existing funding, the advisable level of hybrid issuance is 0%.

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