# pvlib.tracking.SingleAxisTracker¶

class pvlib.tracking.SingleAxisTracker(**kwargs)[source]

Deprecated since version 0.9.0: The SingleAxisTracker class was deprecated in pvlib 0.9.0 and will be removed soon. Use PVSystem with SingleAxisTrackerMount instead.

A class for single-axis trackers that inherits the PV modeling methods from PVSystem. For details on calculating tracker rotation see pvlib.tracking.singleaxis().

Parameters
• axis_tilt (float, default 0) – The tilt of the axis of rotation (i.e, the y-axis defined by axis_azimuth) with respect to horizontal, in decimal degrees.

• axis_azimuth (float, default 0) – A value denoting the compass direction along which the axis of rotation lies. Measured in decimal degrees east of north.

• max_angle (float, default 90) – A value denoting the maximum rotation angle, in decimal degrees, of the one-axis tracker from its horizontal position (horizontal if axis_tilt = 0). A max_angle of 90 degrees allows the tracker to rotate to a vertical position to point the panel towards a horizon. max_angle of 180 degrees allows for full rotation.

• backtrack (bool, default True) – Controls whether the tracker has the capability to “backtrack” to avoid row-to-row shading. False denotes no backtrack capability. True denotes backtrack capability.

• gcr (float, default 2.0/7.0) – A value denoting the ground coverage ratio of a tracker system which utilizes backtracking; i.e. the ratio between the PV array surface area to total ground area. A tracker system with modules 2 meters wide, centered on the tracking axis, with 6 meters between the tracking axes has a gcr of 2/6=0.333. If gcr is not provided, a gcr of 2/7 is default. gcr must be <=1.

• cross_axis_tilt (float, default 0.0) – The angle, relative to horizontal, of the line formed by the intersection between the slope containing the tracker axes and a plane perpendicular to the tracker axes. Cross-axis tilt should be specified using a right-handed convention. For example, trackers with axis azimuth of 180 degrees (heading south) will have a negative cross-axis tilt if the tracker axes plane slopes down to the east and positive cross-axis tilt if the tracker axes plane slopes up to the east. Use calc_cross_axis_tilt() to calculate cross_axis_tilt. [degrees]

• **kwargs – Passed to PVSystem. If the arrays parameter is specified it must have only a single Array. Furthermore if a Array is provided it must have surface_tilt and surface_azimuth equal to None.

Raises
• ValueError – If more than one Array is specified.

• ValueError – If an Array is provided with a surface tilt or azimuth not None.

Methods

 __init__(**kwargs) Initialize self. adrinverter(v_dc, p_dc) Deprecated since version 0.9. calcparams_cec(effective_irradiance, temp_cell) Use the calcparams_cec() function, the input parameters and self.module_parameters to calculate the module currents and resistances. calcparams_desoto(effective_irradiance, …) Use the calcparams_desoto() function, the input parameters and self.module_parameters to calculate the module currents and resistances. calcparams_pvsyst(effective_irradiance, …) Use the calcparams_pvsyst() function, the input parameters and self.module_parameters to calculate the module currents and resistances. Calculates the equivalent resistance of the wires for each array using pvlib.pvsystem.dc_ohms_from_percent() faiman_celltemp(poa_global, temp_air[, …]) Deprecated since version 0.9. first_solar_spectral_loss(pw, airmass_absolute) Use pvlib.atmosphere.first_solar_spectral_correction() to calculate the spectral loss modifier. fuentes_celltemp(poa_global, temp_air, …) Deprecated since version 0.9. get_ac(model, p_dc[, v_dc]) Calculates AC power from p_dc using the inverter model indicated by model and self.inverter_parameters. get_aoi(surface_tilt, surface_azimuth, …) Get the angle of incidence on the system. get_cell_temperature(poa_global, temp_air, …) Determine cell temperature using the method specified by model. get_iam(aoi[, iam_model]) Determine the incidence angle modifier using the method specified by iam_model. get_irradiance(surface_tilt, …[, …]) Uses the irradiance.get_total_irradiance() function to calculate the plane of array irradiance components on a tilted surface defined by the input data and self.albedo. i_from_v(resistance_shunt, …) Wrapper around the pvlib.pvsystem.i_from_v() function. noct_sam_celltemp(poa_global, temp_air, …) Deprecated since version 0.9. pvsyst_celltemp(poa_global, temp_air[, …]) Deprecated since version 0.9. pvwatts_ac(pdc) Deprecated since version 0.9. pvwatts_dc(g_poa_effective, temp_cell) Calcuates DC power according to the PVWatts model using pvlib.pvsystem.pvwatts_dc(), self.module_parameters[‘pdc0’], and self.module_parameters[‘gamma_pdc’]. Calculates DC power losses according the PVwatts model using pvlib.pvsystem.pvwatts_losses() and self.losses_parameters. sapm(effective_irradiance, temp_cell) Use the sapm() function, the input parameters, and self.module_parameters to calculate Voc, Isc, Ix, Ixx, Vmp, and Imp. sapm_celltemp(poa_global, temp_air, wind_speed) Deprecated since version 0.9. sapm_effective_irradiance(poa_direct, …[, …]) Use the sapm_effective_irradiance() function, the input parameters, and self.module_parameters to calculate effective irradiance. sapm_spectral_loss(airmass_absolute) Use the sapm_spectral_loss() function, the input parameters, and self.module_parameters to calculate F1. Scales the voltage, current, and power of the data DataFrame by self.modules_per_string and self.strings_per_inverter. singleaxis(apparent_zenith, apparent_azimuth) Get tracking data. singlediode(photocurrent, …[, ivcurve_pnts]) Wrapper around the pvlib.pvsystem.singlediode() function. snlinverter(v_dc, p_dc) Deprecated since version 0.9.

Attributes

 albedo module module_parameters module_type modules_per_string num_arrays The number of Arrays in the system. racking_model strings_per_inverter surface_azimuth surface_tilt temperature_model_parameters