Basic question about solar panel output

[Locke888]

I am super green but I am wondering if I have 3 panels rated at 400W I will get 1200W in full sun I assume. If I have those panels on my roof facing west what is the output roughly when the sun is in the east about 9am? I am going to guess a total of 300W?or less….

Also how bad is the difference when a random cloud wants to get in the way?

Thanks.

 

[E. Cho]

You will rarely get the full 1200 watts as there are variables, such as panel angles to the sun, clear air and panels, heat as panels are less effecient the hotter they get and are specced at 20-25°C, other losses and they are not 100% efficient anyway and they lose some efficiency with age and again with heat.

Panels facing west and east sun at 09:00 will produce VERY LITTLE power, maybe 50-75 watts not likely 300 watts as they are in full shade, wrong angles, sun is low and low intesity. ... depending on your location and the time of year.

Clouds can drop production by 50-95%. It depends on the cloud density, panel angles, ambient heat. ....

 

[Zapper77]

Plan on 1200x5 or 6 kW on a average day.