To determine the appropriate reliance on hybrid bonds for VERBUND AG's capital structure, we need to evaluate the company's financial health, specifically focusing on its leverage, profitability, and interest coverage. 

1. **EBITDA and Profitability**: VERBUND AG generated an exceptionally strong EBITDA of EUR 3.16 billion in 2022 (up from EUR 1.58 billion in 2021). The profit from operating activities was EUR 2.63 billion, reflecting highly robust operational cash flow.

2. **Leverage (Net Debt to EBITDA)**: 
   - Noncurrent Financial Liabilities (2022-end): ~EUR 2.84 billion
   - Current Financial Liabilities (2022-end): ~EUR 1.11 billion
   - Total Financial Debt: ~EUR 3.95 billion
   - Cash and Cash Equivalents: ~EUR 409 million
   - Net Debt: ~EUR 3.54 billion
   - Net Debt / EBITDA = EUR 3.54 billion / EUR 3.16 billion ≈ 1.12x. 
   A ratio near 1x signifies extremely low leverage and significant balance sheet flexibility.

3. **Interest Coverage**:
   - Interest Expense: ~EUR 101.7 million
   - Interest Coverage Ratio (EBITDA / Interest Expense) = 3,160.6 / 101.7 ≈ 31x.
   This is an exceptionally strong interest coverage ratio, meaning the company can easily meet its debt obligations from its operating earnings.

**Conclusion**: 
Hybrid bonds are generally utilized by companies that are highly leveraged and looking to protect their credit ratings, as rating agencies often treat a portion of hybrid debt as equity. Because hybrid bonds sit lower in the capital structure and carry higher yields (evidenced by the increasing sub-senior delta in the provided market data, reaching 2.295% in 2022), they are an expensive form of financing compared to standard senior debt. 

Given VERBUND AG's stellar cash flows, vast interest coverage, and conservative leverage metrics, the company has unfettered access to cheaper senior debt markets and internal financing. Therefore, there is no structural or financial rationale for the company to rely on more expensive hybrid bonds. 

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