To estimate the FFO / Net Debt ratio for Terna S.p.A. for the year 2022 based on S&P methodology, we need to calculate Funds From Operations (FFO) and Net Debt.

**1. Calculate Funds From Operations (FFO)**

According to S&P Global Ratings methodology, FFO is generally calculated as:
$$FFO = \text{Net Income} + \text{Depreciation and Amortization} + \text{Other Non-Cash Items} + \text{Changes in Working Capital (optional/variant)} - \text{Non-recurring items}$$

A standard simplified proxy for regulated utilities like Terna, often used when detailed cash flow adjustments aren't fully broken down for "non-cash" specifics beyond D&A, is:
$$FFO \approx \text{Profit from Continuing Operations} + \text{Depreciation, Amortization, and Impairment}$$

Let's extract the relevant data for the period 2022-01-01 to 2023-01-01 (Fiscal Year 2022):
*   **Profit Loss From Continuing Operations**: 878,000,000 EUR
*   **Depreciation Amortisation And Impairment Loss...**: 725,700,000 EUR

*Note: S&P often adds back deferred taxes and other non-cash items. Let's look at the Cash Flow from Operations to see if there's a better proxy or if we should stick to the core definition.*
*   **Cash Flows From Used In Operating Activities**: 2,323,700,000 EUR. This includes changes in working capital. S&P FFO typically excludes changes in working capital to measure recurring cash generation capability before working capital fluctuations.
*   Let's check the components added back to Net Income in the indirect cash flow method provided:
    *   Profit Loss From Continuing Operations: 878,000,000
    *   Adjustments for Depreciation/Amortization: 736,100,000 (Note: This differs slightly from the P&L line item of 725.7M, likely due to classification differences or impairments vs depreciation. The Cash Flow statement adjustment is usually the precise add-back for non-cash charges in this context).
    *   Adjustments for Finance Income/Cost: 101,500,000
    *   Adjustments for Income Tax: 356,700,000
    *   Other non-cash movements: -24,100,000
    *   Accruals to provisions: 51,700,000
    *   Gain/Loss on disposals: -6,900,000

Standard S&P FFO definition:
$$FFO = \text{Consolidated Net Income} + \text{Depreciation and Amortization} + \text{Other Non-Cash Charges}$$
It generally does *not* include changes in working capital.

Let's calculate FFO using the standard add-backs to Net Income (attributable to owners or total continuing ops? S&P usually uses Consolidated Net Income including non-controlling interests for the numerator if debt is consolidated, or adjusts accordingly. Given Terna is nearly wholly owned, we can use Total Profit from Continuing Operations or Net Income. Let's use **Profit Loss From Continuing Operations** as the base earnings metric, as discontinued operations are excluded from core operating performance).

Base Earnings (Continuing Ops): 878,000,000 EUR
Add: Depreciation & Amortization (from P&L): 725,700,000 EUR
Add: Deferred Taxes? The tax expense is 355.4M. Cash tax paid is 380.1M. The difference is small.
Add: Non-cash items from Cash Flow statement adjustments excluding working capital changes?
The Cash Flow from Operations *before* working capital changes is given as: **2,072,700,000 EUR**.
This figure ("Cash Flows From Used In Operations Before Changes In Working Capital") is a very strong proxy for FFO in utility analysis, as it represents operating cash generation before the volatility of receivables/payables. S&P FFO is conceptually similar to this, though it might adjust for specific non-recurring items. Given the lack of specific "non-recurring" labels, we will use this robust operating cash flow proxy.

Let's verify this proxy against the manual build:
Net Income (Continuing): 878.0M
+ D&A: 725.7M
+ Deferred Tax/Other Non-Cash:
  - Finance Costs (non-cash portion?): The adjustment for finance income/cost is 101.5M. Finance costs were 121.8M. Interest paid (operating) was 154.8M. This suggests some capitalization or timing differences.
  - Tax Adjustment: 356.7M added back. Tax expense 355.4M.
  - Provisions: 51.7M.
  - Other non-cash: -24.1M.
  - Gain on disposal: -6.9M (subtracted because it's a gain, added back to net income? No, gains are subtracted from NI to get cash flow. In the CF statement, adjustments are added to NI. A negative adjustment means it was a gain included in NI that needs to be removed).
  
  Sum of adjustments in CF before WC:
  $736.1 (D\&A) + 101.5 (Fin) + 356.7 (Tax) - 24.1 (Other) + 51.7 (Prov) - 6.9 (Disp) = 1,215.0 M$
  $NI (Continuing) 878.0 + 1,215.0 = 2,093.0 M$.
  
  The reported "Cash Flows From Used In Operations Before Changes In Working Capital" is **2,072,700,000 EUR**. The slight difference (approx 20M) might be due to the starting Net Income figure (Total Net Income vs Continuing, or attributable vs total).
  Total Net Income: 857.7M.
  $857.7 + 1,215.0 = 2,072.7 M$.
  This matches exactly.
  
  So, **FFO ≈ 2,072,700,000 EUR**.

**2. Calculate Net Debt**

Net Debt = Total Debt - Cash and Cash Equivalents.

From the Balance Sheet at 2023-01-01 (End of 2022):
*   **Long-term Borrowings**: 8,416,700,000 EUR
*   **Current Portion of Long-term Borrowings**: 1,909,300,000 EUR
*   **Short-term Borrowings**: 444,100,000 EUR
*   **Current Financial Liabilities**: 44,900,000 EUR (Often included in debt, but sometimes trade-related. Given "Short-term borrowings" is separate, this might be derivatives or other financial liabilities. S&P typically includes interest-bearing debt. Let's include it to be conservative, or check if it's significant. It's small.)
*   **Noncurrent Financial Liabilities**: 247,200,000 EUR

Total Interest-Bearing Debt:
$8,416.7 + 1,909.3 + 444.1 + 247.2 + 44.9 = 11,062.2 \text{ million EUR}$

Let's refine the Debt definition. S&P defines debt as interest-bearing obligations.
*   Long-term Borrowings: 8,416,700,000
*   Current Portion of Long-term Borrowings: 1,909,300,000
*   Short-term Borrowings: 444,100,000
*   Noncurrent Financial Liabilities: 247,200,000
*   Current Financial Liabilities: 44,900,000

Total Debt = $8,416.7 + 1,909.3 + 444.1 + 247.2 + 44.9 = 11,062.2 \text{ million EUR}$.

Cash and Cash Equivalents (2023-01-01):
*   **Cash And Cash Equivalents**: 2,155,100,000 EUR

Net Debt = Total Debt - Cash
Net Debt = $11,062,200,000 - 2,155,100,000 = 8,907,100,000 \text{ EUR}$.

*Note on Hybrid Bonds*: The equity section lists "Equity Instruments Perpetual Hybrid Bonds" of 989,000,000 EUR. S&P often treats hybrid bonds as 50% debt and 50% equity, or fully as debt depending on the terms. However, in the balance sheet provided, they are classified under Equity ("Equity Instruments..."). If they are treated as equity for accounting, they might be treated as debt-like for S&P ratios. If we treat them as 50% debt:
Adjustment: Add 50% of 989M = 494.5M to Debt.
Adjusted Net Debt = $8,907.1 + 494.5 = 9,401.6 \text{ million EUR}$.

However, standard "Net Debt" calculations from public reports often just take interest-bearing liabilities minus cash. Let's look at the "Finance Costs". Finance costs are 121.8M. If hybrids were fully debt, the coupon would be there. The coupon payable is listed as 21.1M in equity changes. This confirms they are in equity. S&P methodology for utilities often assigns 50% equity credit to hybrids. Let's calculate both ways.
Case 1 (Strict Accounting Debt): Net Debt = 8,907.1M
Case 2 (S&P Adjusted Debt with 50% hybrid): Net Debt = 9,401.6M

Let's check the FFO again. Does FFO include the hybrid coupon? The coupon is a distribution to holders of hybrid bonds, treated as equity distributions (dividends) in the cash flow from financing activities ("Coupon Payable To Holders Of Hybrid Bonds" is in equity changes, not interest expense in P&L? Wait. "Finance Costs" are 121.8M. "Coupon Payable..." is 21.1M. The coupon is likely *not* in Finance Costs if it's an equity instrument. Therefore, FFO (derived from Net Income) has *not* deducted this coupon. If we treat the hybrid as debt, we should arguably add back the coupon to FFO (if it was deducted) or deduct it from FFO (if we treat it as a mandatory payment). Since it's an equity distribution, it's not in Net Income. S&P FFO usually starts with Net Income. If we treat the hybrid as debt, we should adjust FFO to be pre-coupon? No, FFO is a pre-financing cash flow metric usually. But S&P "Adjusted FFO" might deduct mandatory distributions. Let's stick to the standard reported FFO proxy which is Operating Cash Flow before WC.

Let's use the standard Net Debt (Interest bearing debt - Cash).
Net Debt = 8,907,100,000 EUR.
FFO = 2,072,700,000 EUR.

Ratio = $2,072.7 / 8,907.1 \approx 0.2327$.

If we include 50% of hybrids in debt:
Net Debt = 9,401,600,000 EUR.
Ratio = $2,072.7 / 9,401.6 \approx 0.220$.

S&P Global Ratings typically applies a 50% equity credit to hybrid securities for regulated utilities with strong regulatory frameworks. Terna is a regulated utility. Therefore, the 50% equity credit is the appropriate S&P methodology adjustment.

Let's double check the debt components.
Long-term borrowings: 8,416.7
Current portion LT: 1,909.3
Short-term borrowings: 444.1
Non-current financial liabilities: 247.2
Current financial liabilities: 44.9
Total Debt = 11,062.2 M.

Cash = 2,155.1 M.

Net Debt (Accounting) = 8,907.1 M.

Hybrid Bonds = 989 M.
50% Equity Credit -> 50% Debt inclusion = 494.5 M.

S&P Adjusted Net Debt = 8,907.1 + 494.5 = 9,401.6 M.

FFO = 2,072.7 M.

Ratio = 2,072.7 / 9,401.6 = 0.22046...

Let's consider if "Other Reserves" or other items affect FFO.
S&P FFO = Net Income + Depreciation + Amortization + Deferred Taxes + Other Non-Cash Items.
We used the "Cash flow from operations before working capital changes" which is 2,072.7M. This is a very clean proxy for FFO.

Is there any other debt?
"Trade And Other Payables" are not debt.
"Provisions" are not debt.

So the denominator is ~9,402 M.
The numerator is ~2,073 M.

Result: 0.22

Let's try without the hybrid adjustment just in case the prompt implies a simpler "Net Debt" definition (Total Liabilities - Cash? No, Net Debt is interest bearing). If the user expects standard financial ratio calculation without specific S&P hybrid adjustments, it would be 0.23. However, the prompt explicitly asks for "S&P methodology". S&P methodology for utilities *strictly* applies equity credits to hybrids.

Let's verify the Hybrid Bond treatment.
"Equity Instruments Perpetual Hybrid Bonds" 989,000,000.
In the Statement of Changes in Equity, we see "Movement In The Reserve For Equity Instruments" 989,000,000.
And "Coupon Payable To Holders Of Hybrid Bonds" -21,100,000.
This confirms they are classified as equity.
S&P Criteria for Hybrids: For regulated utilities, if the hybrid has strong equity characteristics (deferrable coupons, no maturity), it gets 50% equity credit. Terna's hybrids are typically perpetual and deferrable. Thus, 50% debt, 50% equity.

So, Debt increases by 494.5M.
Net Debt = 8,907.1 + 494.5 = 9,401.6 M.

FFO:
S&P may also adjust FFO for the hybrid coupon if it's treated as debt interest. Since it's not in Net Income, and FFO starts with Net Income, do we subtract it?
S&P Adjusted FFO often deducts mandatory distributions. If the coupon is discretionary/deferrable, it might not be deducted. However, to maintain comparability with debt service, sometimes it is. But usually, FFO is a measure of cash available to service *senior* debt.
If we don't adjust FFO:
Ratio = 2,072.7 / 9,401.6 = 0.22.

If we assume the "standard" Net Debt (without hybrid adjustment) is requested despite the "S&P" label (as some simplified models do):
Ratio = 2,072.7 / 8,907.1 = 0.23.

Given the explicit "S&P methodology" instruction, the hybrid adjustment is the key differentiator. I will proceed with the adjusted figure.

One more check: Did S&P capitalize any interest?
"Interest Costs Capitalised": 24,800,000 EUR.
This is added back to investing cash flows. It is not in Finance Costs (expense).
In the FFO calculation (starting from Net Income), interest expense is already excluded (added back if we were doing EBITDA, but we are doing FFO).
Wait, FFO = Net Income + D&A.
Net Income has deducted Finance Costs (121.8M).
Finance Costs do *not* include the capitalized interest (24.8M) nor the hybrid coupon (21.1M).
So Net Income is after 121.8M interest.
FFO adds back D&A. It does *not* add back interest.
So FFO is after interest expense.
This is correct for FFO.

Is there any other S&P adjustment?
S&P often uses "Adjusted FFO" which might add back deferred taxes.
Deferred Tax Assets changed from 146.6 to 121.0 (Decrease of 25.6).
Deferred Tax Liabilities? Not explicitly listed as a single line, but "Income Tax Expense" is 355.4M. "Income Taxes Paid" is 380.1M.
The difference is small. The "Adjustments For Income Tax Expenses" in CF is 356.7M. This implies the non-cash tax component is roughly equal to the expense, or the adjustment reconciles NI to Cash.
Actually, the line "Cash Flows From Used In Operations Before Changes In Working Capital" is the most reliable "S&P-like" FFO number available in the report data provided, as it strips out working capital volatility which S&P also does (S&P FFO is pre-working capital).

So, Numerator: 2,072.7 M.
Denominator: 9,401.6 M.

Ratio: 0.2204...

Rounding to two decimal places: 0.22.

<answer>0.22</answer>