Start with the site
For factories, workshops, warehouses and production facilities evaluating rooftop solar.
Size for the working day
A large roof does not automatically call for the largest possible plant. Review monthly electricity consumption alongside weekday, weekend and shift patterns. A warehouse with a large shed and light daytime demand has a different case from a factory running motors throughout the day.
The design should explain how much solar electricity is expected to be used on site, how exports are treated in the proposed connection arrangement, and what changes if a shift is added or production slows. Keep energy savings separate from any assumptions about demand charges or tax treatment.
Check the shed before selecting equipment
Roof age, corrosion, sheet condition, structural drawings and the route to the electrical room all affect the scope. A survey should identify safe maintenance access, drainage paths, skylights and areas reserved for future equipment. Structural suitability needs assessment before loading the roof.
Electrical integration deserves its own review: existing transformer and panel capacity, cable routes, earthing, protection and the proposed isolation point. Agree a shutdown plan with the plant team before installation so the work sequence fits production.
Ask for a proposal your operations team can use
Compare a documented layout, equipment schedule, generation assumptions and scope of electrical work. Ask who owns roof repairs, civil work, access equipment, connection coordination and monitoring connectivity. The commercial comparison should use your bills and operating pattern rather than a generic payback figure.
Plan handover while planning installation. Request drawings, equipment records, isolation instructions, monitoring access and a maintenance schedule. Cleaning access and fault response matter throughout the working life of the plant.