THE SOLAR DESIGN PROCESS
The solar system design process usually takes the following into account:
Your needs and requirements (e.g. location, aesthetics, financials, goals)
Geographic location
(generally, closer to the equator, the better)
Orientation
(generally, south facing is better in the northern hemisphere.
Roof Area
(the more usable roof area, at least sufficient for required number of panels, facing south, the better; less area will be required if higher efficiency panels are used)
Shading
(clear, unobstructed access to the sun is preferred)
Roof Type
(solar panels can be installed on almost every roof type using appropriate mounts)
Electric Main Panel
sizing and breaker slot(s) availability.
Selecting solar panel physical size, power output, and quantity
Based on production desired, environmental, and cost.
Mounting and railing
Clearance between roof and panels
(to allow proper air circulation)
Wiring gauge and length
Roof loading
Roof obstructions such as chimneys or vents
Building codes
Layout and routing
of panels, inverters, junction boxes, cut-off switches, wiring, grounding poles, and breakers