How long a home solar project takes, stage by stage

What are the stages of a solar installation timeline?

1. Research and quotes. Collecting bills, getting quotes and choosing an installer. This can take days or weeks, depending on how many quotes you collect.
2. Contract and design. A site visit, a final design and a signed contract.
3. Permits and utility application. Building and electrical permits, and the utility's interconnection request. This is often the slowest stage.
4. Equipment ordering. Panels and inverters arrive, which may take longer if supply is tight.
5. Installation. Typically a few days on site for a standard house.
6. Inspection and utility approval. Electrical inspection, and any meter change or sign-off from the utility.
7. Switch-on. Permission to operate, then monitoring set up.

The on-site work in stage five is described in solar panel installation: steps on site, and the whole sequence in the solar panel installation process in Canada.

Which stage takes longest, and why?

Permits and utility approval, in most cases. Municipal offices have queues and review times that differ widely. Some utilities process interconnection applications in days, others take weeks, and a meter change may need to be scheduled. Ask your installer how long permits took on their last few jobs in your municipality and with your utility, and write the estimate into the contract as a target, not a guarantee.

A second source of delay is the panel and inverter supply chain. A third is the electrical panel: if the house needs a service upgrade, that work may need its own permit and a separate crew. For the permit steps in one province, read solar panel permits in Alberta.

How do the seasons affect the schedule?

Spring and summer are the busiest months for installers, so booking can mean a wait for a crew date. Winter has fewer bookings, but snow, ice, wind and short days can postpone roof work, and snow cover can hide roof conditions until it clears. Installers do work in winter in cold climates, but a schedule needs slack for weather.

There is also a seasonal trade-off for output. A system switched on in late autumn will produce little until spring, which matters if you track payback by month; see solar panels in winter and how to read a solar production estimate. If you hope to catch an incentive deadline, check the rules first, since the date that counts may be the application, the contract or the commissioning.

What can you do to keep the project moving?

• Collect twelve months of bills before the first call, so quotes go faster.
• Ask your installer who submits permits and utility forms, and when.
• Respond promptly to requests for signatures, photos and a roof inspection.
• Fix known roof or electrical problems early, since they can stop an inspection.
• Ask for a written schedule with milestones and who is responsible for each.
• Choose an installer with a track record in your municipality; the solar installer checklist shows what to ask.

How does this compare with community solar projects?

Community-scale projects take far longer. At Drake Landing in Okotoks, Alberta, ground was broken in spring 2005 and the Energy Centre and borehole field were operating in 2007, with collectors on the garages of 52 homes feeding a borehole store that needed years of charging before it performed at full capacity. See the guide on why seasonal storage needs time to ramp up and the how it works page. A rooftop PV system has no such ramp-up and starts producing the day it is approved.

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