Remodel/packages/engine/docs/generation.md

Generation Module

remodel_engine.generation — 25-year hourly simulation for solar, wind, and BESS capacity.

Functions

simulate_solar(config: SolarConfig) → pd.DataFrame

Runs the full solar model chain for 25 years at hourly resolution.

Input: SolarConfig (see schemas/generation.py)

Output: DataFrame with 219 000 rows (25 × 8 760), columns:

Column	Type	Description
year	int16	1–25
hour	int16	0–8759 (within each year)
dc_power_mw	float64	DC output after wiring + mismatch losses
ac_power_mw_pre_clip	float64	After inverter + AC losses, before clipping
ac_power_mw	float64	Final AC output (clipped, availability, soiling, degradation)
degradation_factor	float64	Year-level multiplier (Y1 = 1−deg_y1, monotonically ↓)

Model chain:

irradiance_norm × capacity_dc_mwp × (1 − dc_loss)          → dc_power_mw
dc_power_mw × inverter_η × (1 − ac_loss)                   → ac_power_mw_pre_clip
min(ac_power_mw_pre_clip, capacity_ac_mw)                   → clipped
clipped × availability × (1 − soiling_monthly)              → ac_soiled_base
ac_soiled_base × degradation_factor                         → ac_power_mw

Degradation:

• Year 1: 1 − degradation_y1 (LID + initial)
• Year n: (1 − degradation_y1) × (1 − degradation_annual)^(n−1)

---

simulate_wind(config: WindConfig) → pd.DataFrame

Input: WindConfig

Output: DataFrame with 219 000 rows, columns:

Column	Type	Description
year	int16	1–25
hour	int16	0–8759
wind_speed_hub	float64	Hub-height wind speed (m/s)
power_fraction	float64	Power curve output (0–1)
ac_power_mw	float64	Final AC output
degradation_factor	float64	1.0 in Y1, (1−deg_annual)^(n−1) for Y_n

Model chain:

wind_speed_ref × (hub_h / ref_h)^shear_α               → wind_speed_hub
power_curve(wind_speed_hub)                             → power_fraction
power_fraction × capacity_mw                            → gross_mw
gross_mw × (1−wake) × (1−electrical) × availability    → net_base
net_base × degradation_factor                           → ac_power_mw

Power curve: piecewise-linear, cut-in 3 m/s, rated at 12.5 m/s, cut-out 25 m/s. Defined in catalog/defaults.py::WIND_POWER_CURVE_POINTS.

---

simulate_bess_capacity(config: BessConfig, cum_cycles_per_year: list[float]) → pd.Series

Models physical battery capacity over 25 years. Does not simulate dispatch.

Input:

• config: BessConfig with nameplate MWh, design_cycles, eol_soh, augmentation_schedule
• cum_cycles_per_year: cumulative full-equivalent cycles at end of each year (from dispatch module, or a conservative default)

Output: pd.Series indexed 1–25, values = usable MWh

Degradation:

SOH = max(eol_soh,  1 − cum_cycles/design_cycles × (1 − eol_soh))
usable_mwh = (nameplate + augmentation_so_far) × SOH

---

Catalog profiles

Bundled 8760-hour CSV files in catalog/profiles/:

Location	Solar CSV	Wind CSV	Notes
RJ	solar/RJ_8760.csv	wind/RJ_8760.csv	Rajasthan ~27°N, desert
KA	solar/KA_8760.csv	wind/KA_8760.csv	Karnataka ~13°N, coastal
GJ	solar/GJ_8760.csv	wind/GJ_8760.csv	Gujarat ~23°N, Kutch

Solar CSVs: columns hour, irradiance_norm (0–1). Wind CSVs: columns hour, wind_speed_ms (m/s at 100 m reference height).

Load via catalog.loader.load_solar_profile(location_id) / load_wind_profile(location_id). Results are LRU-cached per process.

Adding a new location profile

1. Create catalog/profiles/solar/<ID>_8760.csv and catalog/profiles/wind/<ID>_8760.csv.
2. Add the ID to catalog/loader._VALID_LOCATIONS.
3. Add a test in tests/unit/test_catalog.py.

CLI

remodel simulate-gen --input scenario.json --output gen.parquet

scenario.json must have a "solar" key (SolarConfig fields) and/or a "wind" key (WindConfig fields).

Parity gate (S1-T10)

See tests/integration/test_parity.py. Currently skipped pending user-supplied fixture values. To unlock: fill tests/fixtures/nagasamudra_inputs.json._expected and remove the pytest.skip.