The transformer sets your schedule and you don't own it
Your panels came in three weeks and the pad-mount transformer is quoted at a year. Crews, WIP, and cash are all parked on a date the utility controls.
Most trades wait on the GC, and a GC delay at least comes with a schedule impact letter and somebody to send it to. A solar sub waits on a regulated monopoly that has no contract with him, owes him no delivery date, and can add scope to his job after the price is locked. The interconnection queue is the only critical path in construction where the party holding up the work is also the party who has to approve it when it's done.
The size of it
You mobilize and demobilize crews against a date you don't control, and jobs stay in WIP two to four extra quarters while overhead keeps burning. A utility upgrade contribution that hits after the price is locked runs $15k to $150k straight off the job.
Nothing you buy sets the schedule on a solar job. Steps and inverters ship in weeks, so the real critical path is the interconnection application review, the supplemental or system impact study, the pad-mount transformer or utility switchgear, and the final meter exchange. Pad-mount transformer lead times have run 40 to 100+ weeks, and LBNL data on projects reaching commercial operation in 2025 puts the median at more than five years from interconnection request to COD. The part that hurts most comes after buyout, when the utility reviews the application and requires a service upgrade or a cost-of-upgrade contribution that was never in the estimate. There's no change order path to the GC for a decision the utility made on its own.
Three moves, in order
Step 06: Project management
Billing dates, change orders, and notices, written as standards that work without anyone chasing them.
What else costs solar contractors money
The same mechanism in other trades
What solar owners ask
Why is my solar job waiting on a utility transformer?
Your panels came in three weeks and the pad-mount transformer is quoted at a year. Crews, WIP, and cash are all parked on a date the utility controls.
What does it cost?
You mobilize and demobilize crews against a date you don't control, and jobs stay in WIP two to four extra quarters while overhead keeps burning. A utility upgrade contribution that hits after the price is locked runs $15k to $150k straight off the job.
What do I do first?
Open every active job and write four dates on the jacket: interconnection application submitted, study status, transformer ordered, and the utility's current quoted lead time.
What are solar contractors supposed to be making?
Solar runs 22% gross margin, 15% overhead and 7% net profit before taxes at $1M–$5M. The all-trade average is 7%, so this trade is right on it. The CFOS target is 10.5%.
Which part of the system fixes it?
The step is number 06, project management. Billing dates, change orders, and notices, written as standards that work without anyone chasing them. It comes from chapter 6 of CONTROL: The Construction Financial Operating System.
Everything on this page is something you can install yourself, andCONTROL is the order to do it in. If you would rather buy the finished result, SPM The Construction CFO does this work for solar contractors as a service. It is a separate firm, Sulphur Prairie Management, LLC, run by the same author.
Wrote CONTROL, the 8 step system behind these figures. More about the author.