|
| 1 | +from __future__ import annotations |
| 2 | + |
| 3 | +import logging |
| 4 | +from dataclasses import dataclass, field |
| 5 | +from typing import Any |
| 6 | + |
| 7 | +import numpy as np |
| 8 | +from geophires_x.GeoPHIRESUtils import is_float |
| 9 | +from scipy.interpolate.interpolate import interp1d |
| 10 | + |
| 11 | +_TOTAL_AFTER_TAX_RETURNS_CASH_FLOW_ROW_NAME = 'Total after-tax returns ($)' |
| 12 | +_IDC_CASH_FLOW_ROW_NAME = 'Debt interest payment ($)' |
| 13 | + |
| 14 | + |
| 15 | +@dataclass |
| 16 | +class PreRevenueCostsAndCashflow: |
| 17 | + total_installed_cost_usd: float |
| 18 | + construction_financing_cost_usd: float |
| 19 | + debt_balance_usd: float |
| 20 | + inflation_cost_usd: float = 0.0 |
| 21 | + |
| 22 | + pre_revenue_cash_flow_profile: list[list[float | str]] = field(default_factory=list) |
| 23 | + |
| 24 | + @property |
| 25 | + def effective_debt_percent(self) -> float: |
| 26 | + return self.debt_balance_usd / self.total_installed_cost_usd * 100.0 |
| 27 | + |
| 28 | + @property |
| 29 | + def total_after_tax_returns_cash_flow_usd(self): |
| 30 | + return self.pre_revenue_cash_flow_profile_dict[_TOTAL_AFTER_TAX_RETURNS_CASH_FLOW_ROW_NAME] |
| 31 | + |
| 32 | + @property |
| 33 | + def pre_revenue_cash_flow_profile_dict(self) -> dict[str, list[float]]: |
| 34 | + """Maps SAM's row names (str) to a list of pre-revenue values""" |
| 35 | + ret = {} |
| 36 | + |
| 37 | + for i in range(len(self.pre_revenue_cash_flow_profile)): |
| 38 | + row_name = self.pre_revenue_cash_flow_profile[i][0] |
| 39 | + if row_name == '': |
| 40 | + continue |
| 41 | + |
| 42 | + row_name = row_name.replace(f'{_CONSTRUCTION_LINE_ITEM_DESIGNATOR} ', '') |
| 43 | + |
| 44 | + row_values = self.pre_revenue_cash_flow_profile[i][1:] |
| 45 | + ret[row_name] = row_values |
| 46 | + |
| 47 | + return ret |
| 48 | + |
| 49 | + @property |
| 50 | + def interest_during_construction_usd(self) -> float: |
| 51 | + return sum( |
| 52 | + [float(it) for it in self.pre_revenue_cash_flow_profile_dict[_IDC_CASH_FLOW_ROW_NAME] if is_float(it)] |
| 53 | + ) |
| 54 | + |
| 55 | + |
| 56 | +def calculate_pre_revenue_costs_and_cashflow(model: 'Model') -> PreRevenueCostsAndCashflow: |
| 57 | + econ = model.economics |
| 58 | + if econ.inflrateconstruction.Provided: |
| 59 | + pre_revenue_inflation_rate = econ.inflrateconstruction.quantity().to('dimensionless').magnitude |
| 60 | + else: |
| 61 | + pre_revenue_inflation_rate = econ.RINFL.quantity().to('dimensionless').magnitude |
| 62 | + |
| 63 | + pre_revenue_bond_interest_rate_param = econ.BIR |
| 64 | + if econ.bond_interest_rate_during_construction.Provided: |
| 65 | + pre_revenue_bond_interest_rate_param = econ.bond_interest_rate_during_construction |
| 66 | + pre_revenue_bond_interest_rate = pre_revenue_bond_interest_rate_param.quantity().to('dimensionless').magnitude |
| 67 | + |
| 68 | + construction_years: int = model.surfaceplant.construction_years.value |
| 69 | + |
| 70 | + # Translate from negative year index input value to start-year-0-indexed calculation value |
| 71 | + debt_financing_start_year: int = ( |
| 72 | + construction_years - abs(econ.bond_financing_start_year.value) if econ.bond_financing_start_year.Provided else 0 |
| 73 | + ) |
| 74 | + |
| 75 | + return _calculate_pre_revenue_costs_and_cashflow( |
| 76 | + total_overnight_capex_usd=econ.CCap.quantity().to('USD').magnitude, |
| 77 | + pre_revenue_years_count=construction_years, |
| 78 | + phased_capex_schedule=econ.construction_capex_schedule.value, |
| 79 | + pre_revenue_bond_interest_rate=pre_revenue_bond_interest_rate, |
| 80 | + inflation_rate=pre_revenue_inflation_rate, |
| 81 | + debt_fraction=econ.FIB.quantity().to('dimensionless').magnitude, |
| 82 | + debt_financing_start_year=debt_financing_start_year, |
| 83 | + logger=model.logger, |
| 84 | + ) |
| 85 | + |
| 86 | + |
| 87 | +_CONSTRUCTION_LINE_ITEM_DESIGNATOR = '[construction]' |
| 88 | + |
| 89 | + |
| 90 | +def _calculate_pre_revenue_costs_and_cashflow( |
| 91 | + total_overnight_capex_usd: float, |
| 92 | + pre_revenue_years_count: int, |
| 93 | + phased_capex_schedule: list[float], |
| 94 | + pre_revenue_bond_interest_rate: float, |
| 95 | + inflation_rate: float, |
| 96 | + debt_fraction: float, |
| 97 | + debt_financing_start_year: int, |
| 98 | + logger: logging.Logger, |
| 99 | +) -> PreRevenueCostsAndCashflow: |
| 100 | + """ |
| 101 | + Calculates the true capitalized cost and interest during pre-revenue years (exploration/permitting/appraisal, |
| 102 | + construction) by simulating a year-by-year phased expenditure with inflation. |
| 103 | +
|
| 104 | + Also builds a pre-revenue cash flow profile for constructionrevenue years. |
| 105 | + """ |
| 106 | + |
| 107 | + logger.info(f"Using Phased CAPEX Schedule: {phased_capex_schedule}") |
| 108 | + |
| 109 | + current_debt_balance_usd = 0.0 |
| 110 | + total_capitalized_cost_usd = 0.0 |
| 111 | + total_interest_accrued_usd = 0.0 |
| 112 | + total_inflation_cost_usd = 0.0 |
| 113 | + |
| 114 | + capex_spend_vec: list[float] = [] |
| 115 | + equity_spend_vec: list[float] = [] |
| 116 | + debt_draw_vec: list[float] = [] |
| 117 | + debt_balance_usd_vec: list[float] = [] |
| 118 | + interest_accrued_vec: list[float] = [] |
| 119 | + |
| 120 | + for year_index in range(pre_revenue_years_count): |
| 121 | + base_capex_this_year_usd = total_overnight_capex_usd * phased_capex_schedule[year_index] |
| 122 | + |
| 123 | + inflation_factor = (1.0 + inflation_rate) ** (year_index + 1) |
| 124 | + inflation_cost_this_year_usd = base_capex_this_year_usd * (inflation_factor - 1.0) |
| 125 | + |
| 126 | + capex_this_year_usd = base_capex_this_year_usd + inflation_cost_this_year_usd |
| 127 | + |
| 128 | + # Interest is calculated on the opening balance (from previous years' draws) |
| 129 | + interest_this_year_usd = current_debt_balance_usd * pre_revenue_bond_interest_rate |
| 130 | + |
| 131 | + debt_fraction_this_year = debt_fraction if year_index >= debt_financing_start_year else 0 |
| 132 | + new_debt_draw_usd = capex_this_year_usd * debt_fraction_this_year |
| 133 | + |
| 134 | + # Equity spend is the cash portion of CAPEX not funded by new debt |
| 135 | + equity_spent_this_year_usd = capex_this_year_usd - new_debt_draw_usd |
| 136 | + |
| 137 | + capex_spend_vec.append(capex_this_year_usd) |
| 138 | + equity_spend_vec.append(equity_spent_this_year_usd) |
| 139 | + debt_draw_vec.append(new_debt_draw_usd) |
| 140 | + interest_accrued_vec.append(interest_this_year_usd) |
| 141 | + |
| 142 | + total_capitalized_cost_usd += capex_this_year_usd + interest_this_year_usd |
| 143 | + total_interest_accrued_usd += interest_this_year_usd |
| 144 | + total_inflation_cost_usd += inflation_cost_this_year_usd |
| 145 | + |
| 146 | + current_debt_balance_usd += new_debt_draw_usd + interest_this_year_usd |
| 147 | + debt_balance_usd_vec.append(current_debt_balance_usd) |
| 148 | + |
| 149 | + logger.info( |
| 150 | + f"Phased CAPEX calculation complete: " |
| 151 | + f"Total Installed Cost: ${total_capitalized_cost_usd:,.2f}, " |
| 152 | + f"Final Debt Balance: ${current_debt_balance_usd:,.2f}, " |
| 153 | + f"Total Capitalized Interest: ${total_interest_accrued_usd:,.2f}" |
| 154 | + ) |
| 155 | + |
| 156 | + pre_revenue_cf_profile: list[list[float | str]] = [] |
| 157 | + |
| 158 | + blank_row = [''] * len(capex_spend_vec) |
| 159 | + |
| 160 | + def _rnd(k_, v_: Any) -> Any: |
| 161 | + return round(float(v_)) if k_.endswith('($)') and is_float(v_) else v_ |
| 162 | + |
| 163 | + def _append_row(row_name: str, row_vals: list[float | str]) -> None: |
| 164 | + row_name_adjusted = row_name.split('(')[0] + f'{_CONSTRUCTION_LINE_ITEM_DESIGNATOR} (' + row_name.split('(')[1] |
| 165 | + pre_revenue_cf_profile.append([row_name_adjusted] + [_rnd(row_name, it) for it in row_vals]) |
| 166 | + |
| 167 | + # --- Investing Activities --- |
| 168 | + _append_row(f'Purchase of property ($)', [-x for x in capex_spend_vec]) |
| 169 | + _append_row( |
| 170 | + f'Cash flow from investing activities ($)', |
| 171 | + # 'CAPEX spend ($)' |
| 172 | + [-x for x in capex_spend_vec], |
| 173 | + ) |
| 174 | + |
| 175 | + pre_revenue_cf_profile.append(blank_row.copy()) |
| 176 | + |
| 177 | + # --- Financing Activities --- |
| 178 | + _append_row( |
| 179 | + f'Issuance of equity ($)', |
| 180 | + [abs(it) for it in equity_spend_vec], |
| 181 | + ) |
| 182 | + |
| 183 | + _append_row( |
| 184 | + # 'Debt draw ($)' |
| 185 | + f'Issuance of debt ($)', |
| 186 | + debt_draw_vec, |
| 187 | + ) |
| 188 | + |
| 189 | + _append_row( |
| 190 | + f'Debt balance ($)' |
| 191 | + # 'Size of debt ($)' |
| 192 | + , |
| 193 | + debt_balance_usd_vec, |
| 194 | + ) |
| 195 | + |
| 196 | + _append_row(_IDC_CASH_FLOW_ROW_NAME, interest_accrued_vec) |
| 197 | + |
| 198 | + _append_row(f'Cash flow from financing activities ($)', [e + d for e, d in zip(equity_spend_vec, debt_draw_vec)]) |
| 199 | + |
| 200 | + pre_revenue_cf_profile.append(blank_row.copy()) |
| 201 | + |
| 202 | + # --- Returns --- |
| 203 | + equity_cash_flow_usd = [-x for x in equity_spend_vec] |
| 204 | + _append_row(f'Total pre-tax returns ($)', equity_cash_flow_usd) |
| 205 | + _append_row(_TOTAL_AFTER_TAX_RETURNS_CASH_FLOW_ROW_NAME, equity_cash_flow_usd) |
| 206 | + |
| 207 | + return PreRevenueCostsAndCashflow( |
| 208 | + total_installed_cost_usd=total_capitalized_cost_usd, |
| 209 | + construction_financing_cost_usd=total_interest_accrued_usd, |
| 210 | + debt_balance_usd=current_debt_balance_usd, |
| 211 | + inflation_cost_usd=total_inflation_cost_usd, |
| 212 | + # pre_revenue_cash_flow_profile_dict=pre_revenue_cf_profile_dict, |
| 213 | + pre_revenue_cash_flow_profile=pre_revenue_cf_profile, |
| 214 | + ) |
| 215 | + |
| 216 | + |
| 217 | +def adjust_phased_schedule_to_new_length(original_schedule: list[float], new_length: int) -> list[float]: |
| 218 | + """ |
| 219 | + Adjusts a schedule (list of fractions) to a new length by interpolation, |
| 220 | + then normalizes the result to ensure it sums to 1.0. |
| 221 | +
|
| 222 | + Args: |
| 223 | + original_schedule: The initial list of fractional values. |
| 224 | + new_length: The desired length of the new schedule. |
| 225 | +
|
| 226 | + Returns: |
| 227 | + A new schedule of the desired length with its values summing to 1.0. |
| 228 | + """ |
| 229 | + |
| 230 | + if new_length < 1: |
| 231 | + raise ValueError |
| 232 | + |
| 233 | + if not original_schedule: |
| 234 | + raise ValueError |
| 235 | + |
| 236 | + original_len = len(original_schedule) |
| 237 | + if original_len == new_length: |
| 238 | + return original_schedule |
| 239 | + |
| 240 | + if original_len == 1: |
| 241 | + # Interpolation is not possible with a single value; return a constant schedule |
| 242 | + return [1.0 / new_length] * new_length |
| 243 | + |
| 244 | + # Create an interpolation function based on the original schedule |
| 245 | + x_original = np.arange(original_len) |
| 246 | + y_original = np.array(original_schedule) |
| 247 | + |
| 248 | + # Use linear interpolation, and extrapolate if the new schedule is longer |
| 249 | + f = interp1d(x_original, y_original, kind='nearest', fill_value="extrapolate") |
| 250 | + |
| 251 | + # Create new x-points for the desired length |
| 252 | + x_new = np.linspace(0, original_len - 1, new_length) |
| 253 | + |
| 254 | + # Get the new, projected y-values |
| 255 | + y_new = f(x_new) |
| 256 | + |
| 257 | + # Normalize the new schedule so it sums to 1.0 |
| 258 | + total = np.sum(y_new) |
| 259 | + if total == 0: |
| 260 | + # Avoid division by zero; return an equal distribution |
| 261 | + return [1.0 / new_length] * new_length |
| 262 | + |
| 263 | + normalized_schedule = (y_new / total).tolist() |
| 264 | + return normalized_schedule |
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