In short
- Most of the installation happens with the plant running normally
- The unavoidable outage is the final tie-in, and it is short
- The tie-in window is agreed at planning stage, not raised on the day
- Work runs under your permit-to-work system, not the contractor’s convenience
What happens with the plant running
Structure fabrication and erection, module mounting, DC cabling on the roof, containment, earthing and most of the inverter installation are all carried out while the plant runs normally. This is the great majority of the work by both time and cost.
What it requires is coordination rather than shutdown: access routes agreed, lifting planned, areas below protected, and the crew working to your site rules.
What genuinely needs an outage
The final tie-in into your panel needs the board dead. That is the unavoidable outage, and it is short relative to the project.
Testing and commissioning after energisation is usually done live, with specific steps agreed with your electrical team.
Agreeing the window before the schedule is fixed
The tie-in window is agreed with your electrical team at planning stage, not raised on the day. Most sites already have a natural window — a maintenance shutdown, a shift change, a weekly off — and the programme is built around it.
Where no such window exists, the sequence can often be split so that the outage is shorter, at some cost in programme. That is a decision for you to make with the facts in front of you.
Safety over a working plant
Work at height above occupied areas needs exclusion zones, edge protection and controlled lifting. Where the roof is over live production, protection below matters as much as protection above.
Your permit-to-work system governs. A contractor who wants to work outside it on your site is telling you something about how the rest of the job will go.
- Access and lifting routes agreed before mobilisation
- Exclusion zones and protection for areas below
- Work under your permit-to-work system
- Tie-in window agreed with your electrical team at planning stage
- Commissioning steps scheduled with the facility team
Questions we are asked about this
Does installing rooftop solar require shutting the factory?
No, not for most of the work. Structure, mounting, DC cabling and earthing are carried out with the plant running. Only the final tie-in into your panel needs an outage, and that window is agreed in advance.
How long is the shutdown for the tie-in?
It is short relative to the overall programme and depends on the connection arrangement. It is scoped during design so you can plan around it rather than being told on the day.
How is safety managed over a working plant?
Work at height above occupied areas is managed with exclusion zones, edge protection and controlled lifting, under your site permit-to-work system.
Work out what this means for your site
The calculator gives a first capacity range from one bill. A survey turns that into something you can put in a business case.
