Pvwattsv8

Photovoltaic system using basic NREL PVWatts V8 algorithm. Does not do detailed degradation or loss modeling. If those are important, please use pvsamv1.

PySAM.Pvwattsv8.default(config) → Pvwattsv8

Load defaults for the configuration config. Available configurations are:

“FuelCellCommercial”

“FuelCellSingleOwner”

“GenericPVWattsWindFuelCellBatteryHybridHostDeveloper”

“GenericPVWattsWindFuelCellBatteryHybridSingleOwner”

“PVWattsBatteryCommercial”

“PVWattsBatteryHostDeveloper”

“PVWattsBatteryResidential”

“PVWattsBatteryThirdParty”

“PVWattsWindBatteryHybridHostDeveloper”

“PVWattsWindBatteryHybridSingleOwner”

“PVWattsWindFuelCellBatteryHybridHostDeveloper”

“PVWattsWindFuelCellBatteryHybridSingleOwner”

“PVWattsAllEquityPartnershipFlip”

“PVWattsCommercial”

“PVWattsCommunitySolar”

“PVWattsHostDeveloper”

“PVWattsLCOECalculator”

“PVWattsLeveragedPartnershipFlip”

“PVWattsMerchantPlant”

“PVWattsNone”

“PVWattsResidential”

“PVWattsSaleLeaseback”

“PVWattsSingleOwner”

“PVWattsThirdParty”

Note

Some inputs do not have default values and may be assigned a value from the variable’s Required attribute. See variable attribute descriptions below.

PySAM.Pvwattsv8.from_existing(data, optional config) → Pvwattsv8: Share data with an existing PySAM class. If optional config is a valid configuration name, load the module’s defaults for that configuration.

PySAM.Pvwattsv8.new() → Pvwattsv8

PySAM.Pvwattsv8.wrap(ssc_data_t) → Pvwattsv8: Load data from a PySSC object.

Warning

Do not call PySSC.data_free on the ssc_data_t provided to wrap()

Pvwattsv8 is a wrapper for the SSC compute module cmod_pvwattsv8.cpp

Interdependent Variables

The variables listed below are interdependent with other variables. If you change the value of one of these variables, you may need to change values of other variables. The SAM user interface manages these interdependent variables, but in PySAM, it is up to you change the value of all interdependent variables so they are consistent. See Interdependent Variables for examples and details.

dc_ac_ratio

gcr

module_type

Functions

class PySAM.Pvwattsv8.Pvwattsv8

This class contains all the variable information for running a simulation. Variables are grouped together in the subclasses as properties. If property assignments are the wrong type, an error is thrown.

Reopt_size_battery_post()

Given a PV system with Utilityrate5 parameters, get the optimal battery size. Wind and additional PV are disabled. Maps SAM compute module inputs to those of the ReOpt API: Pvwattsv5 module linked with Battwatts, Utilityrate5, with Cashloan optional.

For more information on which PySAM variables are used, see: https://github.com/NREL/ssc/blob/develop/ssc/cmod_pvsamv1_eqns.h

For an example, see the ‘Examples’ readthedocs page.

assign(dict) → None

Assign attributes from nested dictionary, except for Outputs

nested_dict = { 'Solar Resource': { var: val, ...}, ...}

execute(int verbosity) → None: Execute simulation with verbosity level 0 (default) or 1

export() → dict: Export attributes into nested dictionary

get_data_ptr() → Pointer: Get ssc_data_t pointer

replace(dict) → None

Replace attributes from nested dictionary, except for Outputs. Unassigns all values in each Group then assigns from the input dict.

nested_dict = { 'Solar Resource': { var: val, ...}, ...}

unassign(name) → None: Unassign a value in any of the variable groups.

value(name, optional value) → None | float | dict | sequence | str: Get or set by name a value in any of the variable groups.

SolarResource Group

class PySAM.Pvwattsv8.Pvwattsv8.SolarResource

assign(dict) → None

Assign attributes from dictionary, overwriting but not removing values.

SolarResource_vals = { var: val, ...}

export() → dict: Export attributes into dictionary.

replace(dict) → None

Replace attributes from dictionary, unassigning values not present in input dict.

SolarResource_vals = { var: val, ...}

albedo

Albedo [0..1]

Info: albedo input array of 1 constant value or 12 monthly values

Type:: sequence

albedo_default

Albedo default [0..1]

Info: default when albedo invalid

Required: False. Automatically set to 0.2 if not assigned explicitly or loaded from defaults.

Type:: float

albedo_default_snow

Albedo default for snow [0..1]

Info: default when albedo invalid and snow model enabled

Required: False. Automatically set to 0.6 if not assigned explicitly or loaded from defaults.

Type:: float

solar_resource_data

Weather data

Info: dn,df,tdry,wspd,lat,lon,tz,elev

Type:: dict

solar_resource_file

Weather file path

Type:: str

use_wf_albedo

Use albedo from weather file [0/1]

Options: 0=albedo input, 1=albedo from weather file (use albedo default if invalid)

Constraints: BOOLEAN

Required: False. Automatically set to 1 if not assigned explicitly or loaded from defaults.

Type:: float

Lifetime Group

class PySAM.Pvwattsv8.Pvwattsv8.Lifetime

assign(dict) → None

Assign attributes from dictionary, overwriting but not removing values.

Lifetime_vals = { var: val, ...}

export() → dict: Export attributes into dictionary.

replace(dict) → None

Replace attributes from dictionary, unassigning values not present in input dict.

Lifetime_vals = { var: val, ...}

analysis_period

Analysis period [years]

Required: Required if system_use_lifetime_output=1

Type:: float

dc_degradation

Annual DC degradation for lifetime simulations [%/year]

Required: Required if system_use_lifetime_output=1

Type:: sequence

system_use_lifetime_output

Run lifetime simulation [0/1]

INOUT: This variable is both an input and an output to the compute module.

Required: False. Automatically set to 0 if not assigned explicitly or loaded from defaults.

Type:: float

SystemDesign Group

class PySAM.Pvwattsv8.Pvwattsv8.SystemDesign

assign(dict) → None

Assign attributes from dictionary, overwriting but not removing values.

SystemDesign_vals = { var: val, ...}

export() → dict: Export attributes into dictionary.

replace(dict) → None

Replace attributes from dictionary, unassigning values not present in input dict.

SystemDesign_vals = { var: val, ...}

array_type

Array type [0/1/2/3/4]

Info: fixed open rack,fixed roof mount,1-axis tracking,1-axis backtracking,2-axis tracking

Constraints: MIN=0,MAX=4,INTEGER

Required: True

Type:: float

azimuth

Azimuth angle [degrees]

Options: E=90,S=180,W=270

Constraints: MIN=0,MAX=360

Required: array_type<4

Type:: float

batt_simple_enable

Enable Battery [0/1]

Constraints: BOOLEAN

Required: False. Automatically set to 0 if not assigned explicitly or loaded from defaults.

Type:: float

bifaciality

Module bifaciality factor [0 or ~0.65]

Required: False. Automatically set to 0 if not assigned explicitly or loaded from defaults.

Type:: float

dc_ac_ratio

DC to AC ratio [ratio]

Constraints: POSITIVE

Required: False. Automatically set to 1.1 if not assigned explicitly or loaded from defaults.

Type:: float

en_snowloss

Enable snow loss model [0/1]

Constraints: BOOLEAN

Required: False. Automatically set to 0 if not assigned explicitly or loaded from defaults.

Type:: float

enable_wind_stow

Enable tracker stow at high wind speeds [0/1]

Constraints: BOOLEAN

Required: False. Automatically set to 0 if not assigned explicitly or loaded from defaults.

Type:: float

gcr

Ground coverage ratio [0..1]

Constraints: MIN=0.01,MAX=0.99

Required: False. Automatically set to 0.3 if not assigned explicitly or loaded from defaults.

Type:: float

gust_factor

Wind gust estimation factor

Required: False for configuration with default inputs. May be required if a variable dependent on its value changes. Example: For the Detailed PV - Single Owner configuration, only Subarray 1 is enabled in the configuration defaults, so Subarray 2 inputs would not be required; if Subarray 2 is enabled, then Subarray 2 inputs is required.

Type:: float

inv_eff

Inverter efficiency at rated power [%]

Constraints: MIN=90,MAX=99.5

Required: False. Automatically set to 96 if not assigned explicitly or loaded from defaults.

Type:: float

losses

Other DC losses [%]

Info: total system losses

Constraints: MIN=-5,MAX=99

Required: True

Type:: float

module_type

Module type [0/1/2]

Info: standard,premium,thin film

Constraints: MIN=0,MAX=2,INTEGER

Required: False. Automatically set to 0 if not assigned explicitly or loaded from defaults.

Type:: float

rotlim

Tracker rotation angle limit [degrees]

Required: False. Automatically set to 45.0 if not assigned explicitly or loaded from defaults.

Type:: float

soiling

Soiling loss [%]

Required: False for configuration with default inputs. May be required if a variable dependent on its value changes. Example: For the Detailed PV - Single Owner configuration, only Subarray 1 is enabled in the configuration defaults, so Subarray 2 inputs would not be required; if Subarray 2 is enabled, then Subarray 2 inputs is required.

Type:: sequence

stow_wspd

Tracker stow wind speed threshold [m/s]

Required: False. Automatically set to 10 if not assigned explicitly or loaded from defaults.

Type:: float

system_capacity

System size (DC nameplate) [kW]

Required: True

The value of system_capacity depends on the following variables:

dc_ac_ratio

Type:: float

tilt

Tilt angle [degrees]

Options: H=0,V=90

Constraints: MIN=0,MAX=90

Required: array_type<4

Type:: float

wind_stow_angle

Tracker angle for wind stow [degrees]

Required: False. Automatically set to 30.0 if not assigned explicitly or loaded from defaults.

Type:: float

xfmr_ll

GSU transformer load loss (resistive) [%(ac)]

Required: False. Automatically set to 0.0 if not assigned explicitly or loaded from defaults.

Type:: float

xfmr_nll

GSU transformer no load loss (iron core) [%(ac)]

Required: False. Automatically set to 0.0 if not assigned explicitly or loaded from defaults.

Type:: float

Shading Group

class PySAM.Pvwattsv8.Pvwattsv8.Shading

assign(dict) → None

Assign attributes from dictionary, overwriting but not removing values.

Shading_vals = { var: val, ...}

export() → dict: Export attributes into dictionary.

replace(dict) → None

Replace attributes from dictionary, unassigning values not present in input dict.

Shading_vals = { var: val, ...}

shading_azal

Azimuth x altitude beam shading losses [%]

Required: False for configuration with default inputs. May be required if a variable dependent on its value changes. Example: For the Detailed PV - Single Owner configuration, only Subarray 1 is enabled in the configuration defaults, so Subarray 2 inputs would not be required; if Subarray 2 is enabled, then Subarray 2 inputs is required.

Type:: sequence[sequence]

shading_diff

Diffuse shading loss [%]

Required: False for configuration with default inputs. May be required if a variable dependent on its value changes. Example: For the Detailed PV - Single Owner configuration, only Subarray 1 is enabled in the configuration defaults, so Subarray 2 inputs would not be required; if Subarray 2 is enabled, then Subarray 2 inputs is required.

Type:: float

shading_en_azal

Enable azimuth x altitude beam shading losses [0/1]

Options: 0=false,1=true

Constraints: BOOLEAN

Required: False. Automatically set to 0 if not assigned explicitly or loaded from defaults.

Type:: float

shading_en_diff

Enable diffuse shading loss [0/1]

Options: 0=false,1=true

Constraints: BOOLEAN

Required: False. Automatically set to 0 if not assigned explicitly or loaded from defaults.

Type:: float

shading_en_mxh

Enable month x Hour beam shading losses [0/1]

Options: 0=false,1=true

Constraints: BOOLEAN

Required: False. Automatically set to 0 if not assigned explicitly or loaded from defaults.

Type:: float

shading_en_string_option

Enable shading string option [0/1]

Options: 0=false,1=true

Constraints: BOOLEAN

Required: False. Automatically set to 0 if not assigned explicitly or loaded from defaults.

Type:: float

shading_en_timestep

Enable timestep beam shading losses [0/1]

Options: 0=false,1=true

Constraints: BOOLEAN

Required: False. Automatically set to 0 if not assigned explicitly or loaded from defaults.

Type:: float

shading_mxh

Month x Hour beam shading losses [%]

Required: False for configuration with default inputs. May be required if a variable dependent on its value changes. Example: For the Detailed PV - Single Owner configuration, only Subarray 1 is enabled in the configuration defaults, so Subarray 2 inputs would not be required; if Subarray 2 is enabled, then Subarray 2 inputs is required.

Type:: sequence[sequence]

shading_string_option

Shading string option

Options: 0=shadingdb,1=average,2=maximum,3=minimum

Constraints: INTEGER,MIN=-1,MAX=4

Required: False. Automatically set to -1 if not assigned explicitly or loaded from defaults.

Type:: float

shading_timestep

Timestep beam shading losses [%]

Required: False for configuration with default inputs. May be required if a variable dependent on its value changes. Example: For the Detailed PV - Single Owner configuration, only Subarray 1 is enabled in the configuration defaults, so Subarray 2 inputs would not be required; if Subarray 2 is enabled, then Subarray 2 inputs is required.

Type:: sequence[sequence]

AdjustmentFactors Group

class PySAM.AdjustmentFactors.AdjustmentFactors

assign() → None: Assign attributes from dictionary

export() → Dict: Export attributes into dictionary

constant: AC Constant loss adjustment [%]

dc_constant: DC Constant loss adjustment [%]

dc_en_hourly: Enable DC hourly-based adjustment factors [0/1]

dc_en_periods: Enable DC period-based adjustment factors [0/1]

dc_en_timeindex: Enable DC lfetime adjustment factors [0/1]

dc_hourly: DC Hourly Adjustment Factors [%]

dc_periods: DC Period-based Adjustment Factors [%]

dc_timeindex: DC Lifetime Adjustment Factors [%]

en_hourly: Enable AC hourly-based adjustment factors [0/1]

en_periods: Enable AC period-based adjustment factors [0/1]

en_timeindex: Enable AC lfetime adjustment factors [0/1]

hourly: AC Hourly Adjustment Factors [%]

periods: AC Period-based Adjustment Factors [%]

sf_constant: DC Constant loss adjustment [%]

sf_en_hourly: Enable SF hourly-based adjustment factors [0/1]

sf_en_periods: Enable SF period-based adjustment factors [0/1]

sf_en_timeindex: Enable SF lfetime adjustment factors [0/1]

sf_hourly: SF Hourly Adjustment Factors [%]

sf_periods: SF Period-based Adjustment Factors [%]

sf_timeindex: SF Lifetime Adjustment Factors [%]

timeindex: AC Lifetime Adjustment Factors [%]

HybridCosts Group

class PySAM.Pvwattsv8.Pvwattsv8.HybridCosts

assign(dict) → None

Assign attributes from dictionary, overwriting but not removing values.

HybridCosts_vals = { var: val, ...}

export() → dict: Export attributes into dictionary.

replace(dict) → None

Replace attributes from dictionary, unassigning values not present in input dict.

HybridCosts_vals = { var: val, ...}

degradation

Annual AC degradation [%]

Required: False. Automatically set to 0.0 if not assigned explicitly or loaded from defaults.

Type:: sequence

land_area

Total land area [acres]

Required: False. Automatically set to 0 if not assigned explicitly or loaded from defaults.

The value of land_area depends on the following variables:

dc_ac_ratio

gcr

module_type

Type:: float

om_capacity

Capacity-based O&M amount [$/kWcap]

Info: !battery,!fuelcell

Required: False. Automatically set to 0.0 if not assigned explicitly or loaded from defaults.

Type:: sequence

om_capacity_escal

Capacity-based O&M escalation [%/year]

Required: False. Automatically set to 0.0 if not assigned explicitly or loaded from defaults.

Type:: float

om_fixed

Fixed O&M annual amount [$/year]

Info: !battery,!fuelcell

Required: False. Automatically set to 0.0 if not assigned explicitly or loaded from defaults.

Type:: sequence

om_fixed_escal

Fixed O&M escalation [%/year]

Required: False. Automatically set to 0.0 if not assigned explicitly or loaded from defaults.

Type:: float

om_land_lease

Land lease cost [$/acre]

Required: False. Automatically set to 0 if not assigned explicitly or loaded from defaults.

Type:: sequence

om_land_lease_escal

Land lease cost escalation [%/yr]

Required: False. Automatically set to 0 if not assigned explicitly or loaded from defaults.

Type:: float

om_production

Production-based O&M amount [$/MWh]

Info: !battery,!fuelcell

Required: False. Automatically set to 0.0 if not assigned explicitly or loaded from defaults.

Type:: sequence

om_production_escal

Production-based O&M escalation [%/year]

Required: False. Automatically set to 0.0 if not assigned explicitly or loaded from defaults.

Type:: float

total_installed_cost

Total installed cost [$]

Required: True

The value of total_installed_cost depends on the following variables:

dc_ac_ratio

gcr

module_type

Type:: float

Outputs Group

class PySAM.Pvwattsv8.Pvwattsv8.Outputs

assign(dict) → None

Assign attributes from dictionary, overwriting but not removing values.

Outputs_vals = { var: val, ...}

export() → dict: Export attributes into dictionary.

replace(dict) → None

Replace attributes from dictionary, unassigning values not present in input dict.

Outputs_vals = { var: val, ...}

ac

AC inverter output power [W]

Type:: sequence

ac_annual

Annual AC output [kWh]

Type:: float

ac_annual_pre_adjust

Annual AC output before system availability [kWh]

Type:: float

ac_monthly

AC output [kWh]

Type:: sequence

ac_pre_adjust

AC inverter output power before system availability [W]

Type:: sequence

alb

Albedo

Type:: sequence

annual_energy

Annual energy [kWh]

Type:: float

annual_energy_distribution_time

Annual energy production as function of time [kW]

Type:: sequence[sequence]

aoi

Angle of incidence [degrees]

Type:: sequence

capacity_factor

Capacity factor based on nameplate DC capacity [%]

Type:: float

capacity_factor_ac

Capacity factor based on total AC capacity [%]

Type:: float

cf_battery_replacement_cost_schedule

replacement O&M costs [$]

Type:: sequence

cf_energy_net

annual energy [kWh]

Type:: sequence

cf_fuelcell_replacement_cost_schedule

replacement O&M costs [$]

Type:: sequence

cf_land_lease_expense

Land lease expense [$]

Type:: sequence

cf_om_capacity

capacity O&M costs [$]

Type:: sequence

cf_om_fixed

fixed O&M costs [$]

Type:: sequence

cf_om_fuel_cost

fossil fuel O&M costs [$]

Type:: sequence

cf_om_land_lease

land lease O&M costs [$]

Type:: sequence

cf_om_production

production O&M costs [$]

Type:: sequence

city

City

Type:: str

dc

DC inverter input power [W]

Type:: sequence

dc_monthly

DC output [kWh]

Type:: sequence

dcsnowderate

DC power loss due to snow [%]

Type:: sequence

df

Weather file diffuse irradiance [W/m2]

Type:: sequence

dn

Weather file beam irradiance [W/m2]

Type:: sequence

elev

Site elevation [m]

Type:: float

gen

System power generated [kW]

Type:: sequence

gh

Weather file global horizontal irradiance [W/m2]

Type:: sequence

inv_eff_output

Inverter efficiency [%]

Type:: sequence

inverter_efficiency

Inverter efficiency at rated power [%]

Type:: float

kwh_per_kw

Energy yield [kWh/kW]

Type:: float

lat

Latitude [degrees]

Type:: float

location

Location ID

Type:: str

lon

Longitude [degrees]

Type:: float

monthly_energy

Monthly energy [kWh]

Type:: sequence

percent_complete

Estimated percent of total completed simulation [%]

Type:: float

poa

Plane of array irradiance [W/m2]

Type:: sequence

poa_monthly

Plane of array irradiance [kWh/m2]

Type:: sequence

shad_beam_factor

External shading factor for beam radiation

Type:: sequence

snow

Weather file snow depth [cm]

Type:: sequence

soiling_f

Soiling factor

Type:: sequence

solrad_annual

Daily average solar irradiance [kWh/m2/day]

Type:: float

solrad_monthly

Daily average solar irradiance [kWh/m2/day]

Type:: sequence

ss_beam_factor

Calculated self-shading factor for beam radiation

Type:: sequence

ss_gnd_diffuse_factor

Calculated self-shading factor for ground-reflected diffuse radiation

Type:: sequence

ss_sky_diffuse_factor

Calculated self-shading factor for sky diffuse radiation

Type:: sequence

state

State

Type:: str

sunup

Sun up over horizon [0/1]

Type:: sequence

tamb

Weather file ambient temperature [C]

Type:: sequence

tcell

Module temperature [C]

Type:: sequence

tpoa

Transmitted plane of array irradiance [W/m2]

Type:: sequence

ts_shift_hours

Time offset for interpreting time series outputs [hours]

Type:: float

tz

Time zone [UTC offset]

Type:: float

wspd

Weather file wind speed [m/s]

Type:: sequence