EDP is a large regulated/utility group with very substantial capital needs and already high leverage. At year-end 2022, liabilities were about €45.0bn versus equity of €13.8bn, and borrowings alone were about €20.0bn. Total assets grew strongly, while equity declined slightly, implying balance-sheet expansion financed mainly by debt/liabilities.

Hybrid bonds can be attractive for a utility like EDP because they provide partial equity credit from rating agencies while generally being cheaper and less dilutive than common equity. That is especially relevant given EDP’s large investment program, renewable growth, and capital-intensive asset base.

However, the case for using the full S&P cap is weakened by several factors:

- Interest rates rose sharply in 2022: 5Y/7Y/10Y swap rates moved from near-zero/negative levels in 2021 to roughly 1.7%–1.9% average in 2022, increasing the cost of issuing long-dated hybrids.
- Corporate credit spreads also widened, and subordinated/hybrid spreads would be meaningfully higher than senior debt.
- Finance costs already doubled from about €876m in 2021 to €1.75bn in 2022, putting pressure on earnings and coverage.
- Cash flow from operations improved strongly, but investing outflows remained very large, so EDP still needs balance-sheet support.
- Using hybrids up to the full 15% adjusted-capital equity-credit cap could be aggressive given the higher coupon burden and refinancing/call-risk environment.

So the optimal stance is not zero or minimal, because hybrids are useful for preserving ratings and funding growth without equity dilution. But it should also not be 100% of the cap because market rates and spreads materially worsened and finance costs are already elevated. A balanced-to-high utilization is appropriate.

Among the options, 75% best fits: EDP should make substantial use of hybrids relative to the S&P cap, but retain some headroom rather than maximizing the cap.

<answer>75%</answer>