TLDR: Please share your experience on how much shading can affect electric current produced by a solar panel.

I got some time to spend with my parents, due to this Corona situation. So, I went to our farm house and setup a solar panel system there. I used 380Wp Mono crystalline PERC panels and the voltage, current I am getting from each one of those panels are satisfactory. Now, I moved back to my place in a city and I live on 13th floor of an old 20 storey apartment. I decided to setup some solar panels for myself too.

I used the same panels that I used in the farm house. The difference is, since its an apartment, I dont have access to roof top. I can put my solar panels outside the window over the ledge, which I did. There is a grill outside the window which casts a shadow. I believe that may be the reason for which I am not getting a decent current output. Can you please take a look at the picture and let me know how much of an impediment is that shadow, from your experience?

This is a 380Wp Mono PERC panel. I have observed it to produce close to 330W under decent sunlight in the farm house where the array is roof top mounted, even though it is a little cloudy at this time of the year. The highest I got from the same panel in my apartment, with those grill shadows is 236W. enter image description here

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Update. As per my coordinates, I should be facing 90 degree to south. I was a little off. Besides, the elevation was not right. Look what I am getting once I fixed that. 379W out of a panel rated for 380W under STC. The temperature at the time of taking the reading is 31 celsius. STC is 25 celsius.

379W out of a panel rated for 380W under STC. The temperature right now is 31 celsius