@KoaAndrew
I would agree that there are cost to remove an old solar panel system who would be part of the installation costs of a new solar panel system and would be eligible for the credit. I am less convinced about other charges for roof preparation. I suspect an argument could be made that if you simply removed the old solar system and got rid of it, the roof would require repair, as all roofs require repair and maintenance from time to time. I believe the clause about installation costs refers more to electrical wiring and mounting brackets and other improvements that are required as part of the electrical system but which do not directly generate electricity. (Although IRC section 48 is about business credits for alternative energy properties, it has some useful definitions and examples that an auditor might reasonably apply to residential installations.)
In short, I don’t think any roof repairs or improvements count toward the solar energy credit. You may want to seek a professional opinion.
