To find the FFO / Net Debt ratio for Acciona SA at the end of 2022, we first need to determine the Funds From Operations (FFO) and the Net Debt from the provided facts.

**1. Calculate Funds From Operations (FFO)**
FFO is universally defined as the Net Cash Flow from Operating Activities adjusted for the changes in Working Capital. It represents the cash generated by a company's regular operations before the impact of working capital fluctuations.
* Cash Flows From Operating Activities (2022) = 1,648,000,000 EUR
* Increase/Decrease In Working Capital (Cash flow impact) = 135,000,000 EUR

FFO = Cash Flows From Operating Activities - Changes In Working Capital
FFO = 1,648,000,000 EUR - 135,000,000 EUR = 1,513,000,000 EUR

**2. Calculate Net Debt**
Net Debt is calculated as Total Financial Debt (Short-term + Long-term) minus Cash and Cash Equivalents and Current Financial Assets. 
*Total Financial Debt (2023-01-01):*
* Noncurrent Portion Of Noncurrent Loans Received = 2,624,000,000 EUR
* Participaciones Preferentes, Obligaciones y Otros Valores Negociables No Corrientes (Non-current bonds) = 3,101,000,000 EUR
* Noncurrent Lease Liabilities = 439,000,000 EUR
* Current Loans Received And Current Portion Of Noncurrent Loans = 553,000,000 EUR
* Participaciones Preferentes, Obligaciones y Otros Valores Negociables Corrientes (Current bonds) = 1,139,000,000 EUR
* Current Lease Liabilities = 72,000,000 EUR

Total Debt = 2,624 + 3,101 + 439 + 553 + 1,139 + 72 = 7,928,000,000 EUR

*Cash and Liquid Assets (2023-01-01):*
* Cash And Cash Equivalents = 2,360,000,000 EUR
* Current Financial Assets = 315,000,000 EUR

Total Liquid Assets = 2,360,000,000 + 315,000,000 = 2,675,000,000 EUR

Net Debt = Total Debt - Total Liquid Assets
Net Debt = 7,928,000,000 EUR - 2,675,000,000 EUR = 5,253,000,000 EUR

**3. Calculate FFO / Net Debt Ratio**
FFO / Net Debt = 1,513,000,000 / 5,253,000,000 = 0.2880258...

<answer>0.288</answer>