EDF should be advised to use hybrid bonds at the high end of the allowable range, but with practical issuance pacing constraints.

Key considerations:

- **Existing hybrid track record is strong.** EDF has issued hybrid/perpetual subordinated instruments before, with first issuance in 2013 and additional issuance in 2021/2022. This is an important positive signal: hybrids are already accepted in its capital structure and investor communication framework.
- **Credit metrics deteriorated severely in 2022.** S&P net debt/EBITDA was negative at **-8.22x** because EBITDA was negative, and S&P FFO/net debt was **-15.79%**, indicating very weak cash generation relative to debt. Moody’s adjusted leverage trend is also described as **deteriorating**.
- **Operating performance was exceptionally weak.** EDF reported:
  - EBITDA/EBE of **-€5.0bn** in 2022 versus **+€18.0bn** in 2021.
  - Operating loss of **€19.4bn**.
  - Net loss of **€18.2bn**.
  - Operating cash flow of **-€7.4bn**, compared with positive **€12.6bn** in 2021.
- **Funding needs are very large.** EDF had heavy investment cash outflows of about **€25.1bn** in 2022, including capex of **€18.3bn**, while operating cash flow was negative. It funded this through substantial borrowing, with **€34.2bn** of proceeds from borrowings in 2022.
- **Balance sheet leverage pressure is significant.** Equity declined from **€62.0bn** to **€46.6bn**, while financial liabilities increased materially, especially current financial liabilities from **€45.0bn** to **€71.8bn** and noncurrent financial liabilities from **€56.5bn** to **€71.1bn**. This points to meaningful refinancing and capital structure pressure.
- **Hybrid bonds can provide rating-relevant support.** Under S&P treatment, hybrids can receive partial equity credit, improving adjusted debt/capital and related leverage metrics. Given the scale of EDF’s funding needs and weakened metrics, hybrid issuance would be more than a modest optimization tool; it would be a meaningful rating-supportive instrument.
- **Cost is a constraint but not decisive.** Market rates rose sharply in 2022, and subordinated spreads were materially higher than in 2020–2021. Hybrid issuance would likely increase marginal funding cost versus senior debt. However, given EDF’s very high leverage pressure, negative cash flow, and strategic importance, the rating and balance-sheet benefits outweigh the cost disadvantage.
- **Annual issuance cap matters.** The prompt indicates a practical maximum of about **€3bn per year**, so over the next 18 months EDF may not be able to reach the full 15% S&P equity-credit cap if starting materially below it. Still, the recommendation should be expressed as the target extent of hybrid use within the allowable framework, not necessarily the exact immediately executable volume.

Overall, EDF fits the guidance for the highest category: very high funding needs, severe deterioration in credit metrics, large capex requirements, existing use of hybrids, and a clear need to preserve investment-grade flexibility. The company should therefore aim to utilize hybrids up to the S&P equity-credit cap, subject to market access and annual issuance capacity.

<answer>15%</answer>