A2A Energia / A2A group shows a credible but not extreme rationale for hybrid issuance over the next 18 months.

Key considerations:

- **Existing hybrid precedent:** The data indicates that the company has already used hybrid bonds recently, and the first hybrid issuance year is noted as 2024. This is a strong positive signal that hybrid capital is viewed as an acceptable part of the capital structure. However, because this appears to be a recent or initial use rather than a long-established, large hybrid layer, it does not by itself justify moving directly to the 15% S&P equity-credit cap.

- **Leverage and rating headroom:** S&P net debt / EBITDA of **3.47x** and FFO / net debt of **23.17%** suggest leverage is meaningful but not distressed for a utility-type issuer. Hybrid issuance would help adjusted leverage because S&P typically grants partial equity credit to qualifying hybrids, but the company does not appear to face acute downgrade pressure based on the provided metrics.

- **Financial trend:** Moody’s adjusted leverage trend is described as **improving**, which argues against a very high hybrid recommendation. If credit metrics are already improving, hybrids are useful for flexibility and rating support, but less necessary as a defensive measure.

- **Funding and capex profile:** The company has sizeable asset growth and investment needs. PPE increased from **€5.6bn to €6.2bn**, intangible assets from **€3.1bn to €3.5bn**, and investing cash flow was about **€1.14bn outflow** in 2022, including substantial capex and acquisitions. This supports some hybrid use, especially for a capital-intensive utility group, but free cash flow turned positive at **€118m**, so funding pressure is not severe.

- **Liquidity and debt access:** Cash increased materially to **€2.58bn**, and the company raised significant borrowings in 2022. This indicates good market access and liquidity. Hybrid issuance is therefore more about capital structure optimization than urgent refinancing.

- **Market cost:** Euro rates rose sharply in 2022, with 5Y/7Y/10Y swaps around **1.7%-1.9%**, and subordinated spreads higher than prior years. Hybrids would likely be more expensive than senior debt and would increase the cash coupon burden. This tempers the recommendation.

Overall, the company has **moderate-to-high capital needs and a clear hybrid precedent**, while leverage is somewhat elevated but improving. That supports a meaningful hybrid layer, but not the maximum cap. The best fit among the options is **7.5% of total adjusted capital**: enough to provide rating flexibility and leverage optimization, without assuming severe downgrade risk or transformational funding needs.

<answer>7.5%</answer>