# pvlib.temperature.sapm_cell#

pvlib.temperature.sapm_cell(poa_global, temp_air, wind_speed, a, b, deltaT, irrad_ref=1000.0)[source]#

Calculate cell temperature per the Sandia Array Performance Model.

See 1 for details on the Sandia Array Performance Model.

Parameters
• poa_global (numeric) – Total incident irradiance [W/m^2].

• temp_air (numeric) – Ambient dry bulb temperature [C].

• wind_speed (numeric) – Wind speed at a height of 10 meters [m/s].

• a (float) – Parameter $$a$$ in (1).

• b (float) – Parameter $$b$$ in (1).

• deltaT (float) – Parameter $$\Delta T$$ in (2) [C].

• irrad_ref (float, default 1000) – Reference irradiance, parameter $$E_{0}$$ in (2) [W/m^2].

Returns

numeric, values in degrees C.

Notes

The model for cell temperature $$T_{C}$$ is given by a pair of equations (Eq. 11 and 12 in 1).

(1)#$T_{m} = E \times \exp (a + b \times WS) + T_{a}$
(2)#$T_{C} = T_{m} + \frac{E}{E_{0}} \Delta T$

The module back surface temperature $$T_{m}$$ is implemented in sapm_module().

Inputs to the model are plane-of-array irradiance $$E$$ (W/m2) and ambient air temperature $$T_{a}$$ (C). Model parameters depend both on the module construction and its mounting. Parameter sets are provided in 1 for representative modules and mounting, and are coded for convenience in TEMPERATURE_MODEL_PARAMETERS.

Module

Mounting

a

b

$$\Delta T [C]$$

glass/glass

open rack

-3.47

-0.0594

3

glass/glass

close roof

-2.98

-0.0471

1

glass/polymer

open rack

-3.56

-0.075

3

glass/polymer

insulated back

-2.81

-0.0455

0

References

1(1,2,3)

King, D. et al, 2004, “Sandia Photovoltaic Array Performance Model”, SAND Report 3535, Sandia National Laboratories, Albuquerque, NM.

Examples

>>> from pvlib.temperature import sapm_cell, TEMPERATURE_MODEL_PARAMETERS
>>> params = TEMPERATURE_MODEL_PARAMETERS['sapm']['open_rack_glass_glass']
>>> sapm_cell(1000, 10, 0, **params)
44.11703066106086