Based on the financial facts provided for HERA S.P.A. for the fiscal year ended December 31, 2022, the entity should be advised to issue **0%** of its total adjusted capital in hybrid bonds for the following reasons:

1. **Low Refinancing Needs**: Hera has built up a very strong liquidity position. The company holds €1.94 billion in cash and cash equivalents (up from €885 million the prior year) due to €2.12 billion in proceeds from long-term borrowings. This comfortably covers its current financial liabilities of €650 million, meaning immediate refinancing needs are practically non-existent. 

2. **Transient Leverage Pressures**: While net debt increased (to roughly €4.4 billion from €3.3 billion in 2021), this was largely driven by an extraordinary and temporary working capital absorption (notably a €1.28 billion increase in trade receivables) tied to the European energy crisis and commodity price spikes in 2022, which caused revenues to virtually double. Because working capital fluctuations typically unwind and rating agencies tend to look through such temporary anomalies for regulated utilities, structural leverage deterioration is limited. 

3. **No Existing Hybrids**: There is no historical presence of hybrid bonds or subordinated perpetual notes within the company's equity reserves, indicating that capital structure optimization via hybrids is not a core part of its current financial policy.

4. **Prohibitive Cost of Issuance**: Market data shows that the interest rate environment deteriorated significantly in 2022. The 10Y Swap curve jumped to ~1.92% (up from near-zero), and the subordinated-senior delta widened to ~2.30%. Issuing a hybrid bond in this environment would materially and unnecessarily increase the company's cost of debt for a leverage optimization it does not fundamentally require. 

5. **Stable Profitability**: Despite the turbulent revenue and working capital environments, the company's operating stability is proven by its resilient EBITDA proxy (Operating Profit + D&A), which stood at a robust €1.20 billion in 2022, comparable to €1.22 billion in 2021. This demonstrates strong profitability dynamics that can defend its credit profile without the support of equity-like debt.

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