PV Panel Options...

We believe we need need 23 panels of 210 watts, making a  ..................Following the basic criteria that the PV panels should face south, not be shaded and not too far from the house to reduce transmission losses, the two best locations would be on the shed or on the barn.

The shed or the barn are the main options for the location PV panels

LOCATION OF PANELS


This table shows the pros and cons of the locations. Generally the optimum angle for PV panels is about 30 degrees to the horizontal but 'Angle of Panels' (below) explains why we are considering vertical panels.

The pros and cons of the different panel locations

The best position will be ‘vertical on barn’ depending on:

-  The angle to horizontal (90 degrees) receiving enough daylight.

 - Not being shaded by the house.

ANGLE OF PANELS (On barn roof vs. Vertical on barn)

Using the software on PVGIS I compared the electricity production for the different positions of the PV panels. The amount of electricity required per day is around 5kWh throughout the year (as shown by the red line). The graphs show that the roof PV panels produce more electricity throughout the year compared to vertical PV panels. However, the vertical panels take better advantage of the low winter sun, when we are short of electricity, while still producing enough electricity in summer.

Graphs to show that vertical panels will be preferable to panels at 15 degrees

SHADING ON PANELS

The drawings below show potential shading on the panels. It can be seen in late September there is no shading on panels. In late November the panels start to be shaded in late afternoon. However, how much electricity are the panels going to be producing after 3pm in the winter even if not shaded?

Our initial thought is that the benefit of ease of installation outweighs the minimal loss of electricity production for an hour a day in the winter months.

Shading the on the panels at different times of the year and throughout the day