def pvsyst_celltemp(poa_global, temp_air, wind_speed=<NUM_LIT:1.0>, eta_m=<NUM_LIT:0.1>,<EOL>alpha_absorption=<NUM_LIT>, model_params='<STR_LIT>'):
pvsyst_presets = TEMP_MODEL_PARAMS['<STR_LIT>']<EOL>if isinstance(model_params, str):<EOL><INDENT>model_params = model_params.lower()<EOL>constant_loss_factor, wind_loss_factor = pvsyst_presets[model_params]<EOL><DEDENT>elif isinstance(model_params, (tuple, list)):<EOL><INDENT>constant_loss_factor, wind_loss_factor = model_params<EOL><DEDENT>else:<EOL><INDENT>raise TypeError(<EOL>"<STR_LIT>"<EOL>)<EOL><DEDENT>total_loss_factor = wind_loss_factor * wind_speed + constant_loss_factor<EOL>heat_input = poa_global * alpha_absorption * (<NUM_LIT:1> - eta_m)<EOL>temp_difference = heat_input / total_loss_factor<EOL>temp_cell = temp_air + temp_difference<EOL>return temp_cell<EOL>
Calculate cell temperature using an emperical heat loss factor model
as implemented in PVsyst.

The heat loss factors provided through the 'model_params' argument
represent the combined effect of convection, radiation and conduction,
and their values are experimentally determined.

Parameters
----------
poa_global : numeric
    Total incident irradiance in W/m^2.

temp_air : numeric
    Ambient dry bulb temperature in degrees C.

wind_speed : numeric, default 1.0
    Wind speed in m/s measured at the same height for which the wind loss
    factor was determined.  The default value is 1.0, which is the wind
    speed at module height used to determine NOCT.

eta_m : numeric, default 0.1
    Module external efficiency as a fraction, i.e., DC power / poa_global.

alpha_absorption : numeric, default 0.9
    Absorption coefficient

model_params : string, tuple, or list (no dict), default 'freestanding'
    Heat loss factors to be used.

    If string, can be:

        * 'freestanding' (default)
            Modules with rear surfaces exposed to open air (e.g. rack
            mounted).
        * 'insulated'
            Modules with rear surfaces in close proximity to another
            surface (e.g. roof mounted).

    If tuple/list, supply parameters in the following order:

        * constant_loss_factor : float
            Combined heat loss factor coefficient. Freestanding
            default is 29, fully insulated arrays is 15.

        * wind_loss_factor : float
            Combined heat loss factor influenced by wind. Default is 0.

Returns
-------
temp_cell : numeric or Series
    Cell temperature in degrees Celsius

References
----------
[1]"PVsyst 6 Help", Files.pvsyst.com, 2018. [Online]. Available:
http://files.pvsyst.com/help/index.html. [Accessed: 10- Dec- 2018].

[2] Faiman, D. (2008). "Assessing the outdoor operating temperature of
photovoltaic modules." Progress in Photovoltaics 16(4): 307-315.