Based on the financial data and the provided guidelines, here is the assessment for ERG S.P.A.'s potential issuance of hybrid bonds over the next 18 months:

1. **Historical Hybrid Issuance:** The most critical indicator in this assessment is that ERG S.P.A. has never issued hybrid bonds (First year of hybrid bond issuance: never). The company currently has no hybrid bonds in its capital structure. Historically, an entity's lack of prior hybrid issuance is a very strong and reliable signal that it has fundamental reasons to avoid this instrument, whether due to a conservative financial policy, sufficient headroom in its credit metrics, or a lack of appetite for the structural subordination and higher costs associated with hybrids.

2. **Refinancing and Liquidity Needs:** Looking at the 2022 cash flow statement, ERG displays a robust ability to generate cash internally. The company's cash flow from operations was robust at approximately €458.9 million. Furthermore, the firm successfully executed substantial deleveraging over the period, repaying approximately €1 billion in current borrowings ("Cash Flows From Used In Increase Decrease In Current Borrowings" was -€1,000,134,000) and over €350 million in non-current borrowings. This massive reduction in debt signals that the company has low refinancing needs and does not face significant leverage pressure that would necessitate the equity credit provided by a hybrid bond.

3. **Profitability and Credit Metrics:** ERG posted a strong net profit of €383.1 million for 2022 (up from €174.5 million in 2021) and increased its total equity significantly from €1.57 billion to €2.05 billion. With a growing equity base and heavily reduced borrowings, the company's capital structure is organically strengthening. There is no indication of material downgrade risk that would force the company to issue hybrid bonds to protect its investment-grade rating or optimize adjusted leverage trajectories.

4. **Cost of Debt:** Market data indicates a sharp increase in base rates and credit spreads in 2022 (e.g., the 5-year swap curve jumped from -0.264% in 2021 to 1.726% in 2022, and the subordinated delta widened). Introducing hybrid bonds now would materially increase ERG's overall cost of debt compared to its existing senior funding or internally generated capital, making it a highly inefficient funding choice under current market conditions. 

In conclusion, given the absence of previous hybrid issuance, robust profitability, significant debt reduction, and a higher interest rate environment, ERG S.P.A. does not need to—and is highly unlikely to—issue hybrid bonds. 

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