To determine the appropriate extent to which EDP, S.A. should utilize hybrid bonds, we must analyze its financial position, capital structure, refinancing needs, and the cost environment, mapping these factors to the provided S&P Global Ratings guidance.

**1. Financial Position and Leverage Analysis**
*   **Equity and Debt:** As of December 31, 2022, Total Equity is €13,834.6 million. Total Liabilities are €44,981.8 million.
*   **Adjusted Capital Base:** For the purpose of hybrid equity credit calculation, "Total Adjusted Capital" is generally defined as Equity + Adjusted Debt. While specific "Adjusted Debt" figures (netting cash, etc.) are not explicitly provided as a single line item, we can approximate the scale. Total Debt (Long-term borrowings + Current borrowings) is approximately €15.78bn + €4.24bn = €20.02bn. Even if we assume a conservative Adjusted Debt figure close to Gross Debt due to the nature of utility balance sheets, the Total Adjusted Capital is roughly €13.8bn (Equity) + ~€20bn (Debt) ≈ €33.8bn.
*   **Hybrid Capacity:** The prompt asks for the percentage of *total adjusted capital*.
    *   15% of ~€33.8bn is approximately €5.07bn.
    *   11.25% is approximately €3.8bn.
    *   7.5% is approximately €2.5bn.
*   **Current Hybrid Status:** The prompt implies we must consider the "current starting point." EDP has historically utilized hybrid instruments. If existing hybrids are already counted as equity for rating purposes, issuing *new* hybrids increases the denominator (Total Capital) and the numerator (Hybrid Equity). The question asks for the *extent* of utilization, implying the target ratio of hybrids within the total capital structure.

**2. Refinancing Needs and Cash Flow**
*   **Cash Flow from Operations:** EDP generated €3,777.8 million in operating cash flow in 2022, a significant increase from €2,019.9 million in 2021. This indicates strong operational performance.
*   **Investing Activities:** Cash used in investing activities was €3,231.9 million, primarily driven by Capex (€3.5bn paid for PPE/Intangibles). This shows a high capex intensity typical of utilities transitioning to renewables.
*   **Financing Activities:** The company had a net cash inflow from financing of €1,099.6 million. It raised €4.45bn in debt and repaid €1.58bn.
*   **Refinancing Wall:** Current borrowings are €4.24bn. Long-term borrowings are €15.78bn. The company is actively managing its debt maturity profile. The increase in current borrowings from €1.52bn (2021) to €4.24bn (2022) suggests a near-term refinancing need or a shift in debt classification.

**3. Cost of Capital and Market Environment**
*   **Interest Rates:** The swap curves show a dramatic increase in rates in 2022 (10Y average swap went from -0.14% in 2020 to 1.93% in 2022). The cost of debt has risen significantly.
*   **Hybrid Cost:** Hybrid bonds carry a higher coupon than senior debt. In a rising rate environment, the cost of hybrids increases. However, they provide equity credit (usually 50-100% depending on terms), which lowers reported leverage ratios (Debt/EBITDA, FFO/Debt).
*   **Guidance Check:**
    *   *0%:* "Cost of hybrid will materially increase the current cost of debt." This is true, but EDP has high capex needs.
    *   *3.75%:* "Mild leverage optimization."
    *   *7.5%:* "Moderate refinancing or acquisition needs... Hybrid issuance meaningfully improves adjusted leverage metrics."
    *   *11.25%:* "High capex intensity... Investment grade preservation strongly dependent on capital structure optimization."
    *   *15%:* "Very high refinancing needs... Material downgrade risk without hybrid support."

**4. Strategic Assessment**
*   **Capex Intensity:** EDP is in a heavy investment phase (Renewables transition). Capex payments were €3.5bn in 2022. This aligns with "High capex intensity."
*   **Leverage Pressure:** With €20bn in debt and €13.8bn in equity, the Debt-to-Equity ratio is ~1.45x. For a utility, this is moderate but can be high depending on the rating agency's adjusted metrics. Improving leverage ratios is crucial to maintain investment grade ratings, especially as interest expenses rise (Finance costs doubled from €875m to €1.75bn).
*   **Rating Preservation:** The surge in finance costs pressures Net Income and FFO. Using hybrids allows EDP to raise permanent capital that counts as equity for rating purposes, thereby offsetting the leverage impact of new debt required for capex.
*   **Comparison to Options:**
    *   EDP does not appear to be in *distress* or facing *material downgrade risk* solely due to leverage if managed well (ruling out 15% as a desperate measure).
    *   However, the capex is significant and ongoing. A 3.75% or 7.5% issuance might be insufficient to meaningfully offset the leverage impact of the required debt funding for the renewable transition in a high-rate environment.
    *   The 11.25% level corresponds to "High capex intensity" and "Investment grade preservation strongly dependent on capital structure optimization." Given the doubling of finance costs and the strategic imperative to invest in renewables (which is capital intensive), optimizing the capital structure via hybrids is a key tool.
    *   The prompt limits issuance to €3bn/year. 11.25% of ~€34bn is ~€3.8bn. This is slightly above the annual cap, suggesting that reaching 11.25% would take more than one year or require a larger single issuance if permitted (but the prompt says "consider a maximum amount... of up to 3 billion"). If the target is the *stock* of hybrids as a % of capital, and they currently have some, issuing €3bn might move them toward this tier.
    *   Let's look at the "Cost" guidance for 11.25%: "Cost of hybrid will have a marginal impact on the current cost of debt." This is arguably incorrect in a rising rate environment where hybrids are expensive, *unless* the alternative is even more expensive equity issuance or constrained senior debt capacity. However, the *strategic* fit of "High capex intensity" is the strongest driver here.

**Re-evaluating based on "Starting Point":**
If EDP already has hybrids outstanding (which it does, historically ~€2-3bn range), adding €3bn would increase the total hybrid stock.
Total Capital ~€34bn.
If current hybrids are ~€2bn, that's ~6%.
Adding €3bn brings it to ~€5bn, which is ~14.7%. This approaches the 15% cap.
However, the guidance for 15% requires "Very high refinancing needs OR transformational capex... Material downgrade risk." EDP is strong (A-range typically). It is not in distress.
The guidance for 11.25% fits "High capex intensity" and "Significant leverage pressure" (due to rising rates and investment needs).
The guidance for 7.5% fits "Moderate refinancing... meaningfully improves adjusted leverage."

Given EDP's strong operating cash flow growth (€3.7bn) covering most capex (€3.5bn), the *need* for external financing is for the gap and refinancing. The leverage is not critical. The "Material downgrade risk" for 15% is too strong. The "Mild" nature of 3.75% is too weak for a major utility in transition.
Between 7.5% and 11.25%:
EDP's finance costs doubled. This puts pressure on coverage ratios. Hybrids help equity base.
The "High capex intensity" descriptor for 11.25% is very relevant for EDP's renewable strategy.
However, EDP is a high-quality issuer. Over-leveraging with expensive hybrids is not ideal.
Let's look at the specific constraint: "maximum amount of hybrid issued per year of up to 3 billion euros."
If the recommendation is a *target percentage* of total capital:
11.25% of €34bn = €3.8bn.
7.5% of €34bn = €2.55bn.

If the company issues €3bn (the max allowed), it moves closer to 11.25%.
Is the situation "Investment grade preservation strongly dependent on capital structure optimization"? For a company with €3.7bn OCF and €1.1bn Net Income, probably not *strongly dependent* in a distress sense, but *strategically dependent* to maintain headroom for further growth.

Let's look at the 7.5% criteria again: "Moderate refinancing or acquisition needs... Hybrid issuance meaningfully improves adjusted leverage metrics."
EDP has moderate/high refinancing needs (€4.2bn current debt).
The cost of hybrids is high now. Issuing too much (15%) would drag on earnings.
11.25% is aggressive. 7.5% is balanced.

However, note the "Finance Costs" increase. EBITDA was €4.5bn. Interest is €1.75bn. Coverage is ~2.5x. This is decent but not robust for a high-leverage scenario. Hybrids (with deferred interest options) can help manage this.
Most importantly, S&P often views utilities with high renewable capex as needing hybrid support to keep leverage in check.
The "11.25%" option aligns with "High capex intensity." EDP's capex is high relative to its size.
The "15%" option aligns with "Transformational capex." EDP's shift to renewables is transformational. But "Material downgrade risk" is the key disqualifier for 15%. EDP is stable.

Therefore, 11.25% seems the most appropriate strategic target for a utility undergoing significant capital transformation with high capex, where leverage management is key to preserving the rating profile against rising interest costs.

<answer>11.25%</answer>