Temperature Losses

[azizsye1]

Hello,

I wanted to my know why my PV Loss due to temperature is higher on a 10 degree tilt compared to a 5 degree tilt with the same footprint(i.e. same interow spacing, space between panels etc)

Thanks.

[unilhexio]

Hi,

May be that in your case the global tilted irradiation is higher for 10º tilt.

[André Mermoud]

As mentioned in the help, we propose a model (energy balance) for the determination of the PV module temperature during the simulation, but we don't have assessed values for the parameters.

The parameters Uc and Uv are to be specified by the user. They are highly dependent on the layout of the system and the wind measured values (just above the plant or meteorological at 10m). But we don't avail of reliable long-term measurements for these parameters in any conditions (free, insulated, with air duct, as function of the tilt, etc). The only values proposed are according to my own measurements on 2 or 3 installations, or the values proposed by a third party in the US for free-standing disposition:

Uc = 25 W/m²·k, Uv = 1.2 W/m²·k / m/s

But I am not able to provide evolution as a function of the tilt angle.

To my mind, theoretical air circulation thermal models may help, but are not sufficiently reliable.

This should be measured on-site (the parameters may be extracted from long-term measurements of TAmb, Tarray, Ginc and Vind velocity).

[Renu222]

how can i find the Short circuit current, Open circuit current & filling Factor for a particular orientation under Stand alone in the Pv system software.Please reply