Guide
Model picks
The method of each calculation step, by path and by step
What it is
The method each step of the calculation uses. model.path applies one of the paths: pvperf, pvsyst_8, pvwatts, sam. model.<step> sets the method and the variant of one step on top of the path. A step left out keeps the path's method. Without a path, the pvperf path sets each step whose fields the request leaves out, and the steps you name change on top.
How to use it
Send model.path to run a path as the Model page resolves it for the project. Add a step to change it, for example {"path": "pvsyst_8", "transposition": {"method": "perez", "variant": "sam"}}. A variant left out is the method's default variant, listed first below. Without model.path, the pvperf path sets each step whose fields the request leaves out. A field the request sends keeps its value, and so do the other fields of its step. GET /api/defaults and the simple run's request carry the pvperf path's picks for their own project, written into the sections. After a change to the module, the inverter, the racking or the weather, send model.path to resolve the path again for the new project. POST /api/model/{path}/describe with a run body lists each step's method in use, the method of each path, each method's variants and the fields each pick writes.
Values
| Step | Key | method |
variant (default first) |
|---|---|---|---|
| Solar position | model.solar_position |
nrel_spa |
published, sam |
michalsky |
— | ||
pvsyst_ephemeris |
— | ||
| Sun timing | model.sun_timing |
sunlit_midpoint |
— |
interval_midpoint |
— | ||
| Dark intervals | model.dark_intervals |
zero_irradiance |
— |
isotropic_diffuse |
— | ||
| Transposition | model.transposition |
perez |
published, pvsyst_8, sam |
hay_davies |
— | ||
isotropic |
— | ||
| Circumsolar treatment | model.circumsolar |
as_beam |
— |
as_diffuse |
— | ||
| Low-light threshold | model.threshold |
plane_threshold |
— |
not_modeled |
— | ||
| Horizon shading | model.horizon |
quaschning_hanitsch |
published, pvsyst_8 |
timestep_beam_gate |
— | ||
not_modeled |
— | ||
| Row-to-row shading | model.row_shading |
deline |
published, sam |
quaschning_hanitsch |
published, pvsyst_8 |
||
appelbaum_bany |
published, pvsyst_8, pvwatts, sam |
||
shading_factor_table |
every_degree, pvsyst_8 |
||
not_modeled |
— | ||
| Sky-diffuse masking | model.sky_masking |
sky_view_factor |
— |
passias_kallback |
— | ||
isotropic_integral |
— | ||
| Backtracking | model.backtracking |
planar |
published, pvsyst_8, custom_width |
terrain_aware |
gcr_width, active_band_width, custom_width |
||
| Irradiance tracking | model.irradiance_tracking |
best_plane_angle |
full_climb, pvsyst_8 |
flat_on_diffuse |
— | ||
not_modeled |
— | ||
| Beam incidence angle | model.beam_iam |
fresnel |
published, pvsyst_8_ar, pvsyst_8_normal |
ashrae |
— | ||
de_soto |
published, sam |
||
module_iam_profile |
— | ||
measured_table |
— | ||
| Diffuse incidence angle | model.diffuse_iam |
brandemuehl_beckman |
— |
sky_and_ground_integral |
true_angle, pvsyst_8, pvsyst_6_8 |
||
| Soiling | model.soiling |
monthly_fractions |
— |
not_modeled |
— | ||
| Rear irradiance | model.rear_irradiance |
infinite_sheds |
— |
marion |
published, pvwatts, sam |
||
unlimited_sheds_2d |
— | ||
strip_view_factors |
— | ||
not_modeled |
— | ||
| Cell temperature | model.cell_temperature |
prilliman |
published, pvsyst_8 |
noct |
sam, published, pvwatts |
||
faiman |
— | ||
sapm |
— | ||
fuentes |
published, pvwatts |
||
| Module model | model.module |
pvwatts_dc |
— |
mermoud |
published, pvsyst_8 |
||
cec_6_parameter |
published, sam_this_module, pvwatts_representative |
||
| Spectral correction | model.spectral |
lee_panchula |
published, pvsyst_8 |
sapm_spectral |
published, sam |
||
not_modeled |
— | ||
| Snow | model.snow |
townsend |
— |
not_modeled |
— | ||
| Electrical shading | model.electrical_shading |
according_to_strings |
— |
module_layout |
— | ||
not_modeled |
— | ||
| DC derates | model.dc_derates |
current_voltage_split |
— |
flat_derates |
— | ||
| Rear mismatch | model.rear_mismatch |
deline |
published, sam |
flat_fraction |
— | ||
not_modeled |
— | ||
| DC wiring | model.dc_wiring |
i2r_at_mpp_current |
— |
load_ratio |
— | ||
flat_fraction |
— | ||
| MPPT inputs | model.mppt_inputs |
one_input_per_string |
— |
shared_operating_point |
— | ||
| Inverter efficiency | model.inverter_efficiency |
pvwatts_inverter |
— |
sandia |
published, pvwatts |
||
efficiency_curves |
— | ||
parabolic_voltage_blend |
— | ||
flat_efficiency |
— | ||
| Inverter limits | model.inverter_limits |
iv_operating_point |
exact_point, pvsyst_8 |
mppt_voltage_clipping |
— | ||
power_caps |
— | ||
ac_nameplate_clip |
— | ||
| Night consumption | model.night_consumption |
night_draw |
— |
not_modeled |
— | ||
| AC wiring | model.ac_wiring |
kp2_loss |
— |
flat_fraction |
— | ||
| AC resistive reference | model.ac_resistive_reference |
inverter_output |
— |
cascade |
— | ||
| AC power reference | model.ac_power_reference |
inverter_nameplate |
— |
stc_reference_power |
— | ||
| MV transformer | model.mv_transformer |
iron_and_copper |
— |
not_modeled |
— | ||
| MV line | model.mv_line |
resistive_loss |
— |
not_modeled |
— | ||
| HV transformer | model.hv_transformer |
iron_and_copper |
— |
not_modeled |
— | ||
| HV line | model.hv_line |
resistive_loss |
— |
not_modeled |
— | ||
| Transmission losses | model.transmission |
flat_fractions |
— |
not_modeled |
— | ||
| Auxiliaries | model.auxiliaries |
day_and_night_draw |
— |
not_modeled |
— | ||
| Grid limit | model.grid_limit |
at_injection_point |
to_ceiling, pvsyst_8 |
at_inverter_output |
to_limit, pvsyst_8 |
||
not_modeled |
— | ||
| Unavailability | model.unavailability |
fraction_and_periods |
— |
not_modeled |
— | ||
| Power factor | model.power_factor |
inside_rows |
— |
own_row |
— | ||
| Nameplate schedule | model.nameplate_schedule |
apparent_power |
— |
active_power |
— |