@kwrightmti --
If the second "separate" system you installed was to the same principal residence as the first system, you'd be unable to take a second credit. But if the second system was installed to a new, subsequent principal residence, you'd be OK.
"If all or any part of the credit provided for under this subsection was allowed or carried over from a prior taxable year or years, a taxpayer shall reduce the allowable credit for additional qualifying expenditures in a subsequent tax year by the amount of the credit previously allowed or carried over; provided however that a credit previously allowed or carried over from a prior taxable year or years shall not be taken into account in determining the allowable credit for the purchase and installation of a solar or wind energy system in a subsequent principal residence."
https://codes.findlaw.com/ny/tax-law/tax-sect-606.html
In other words, the State of New York credit is per principal residence, not per system.
**Answers are correct to the best of my ability but do not constitute tax or legal advice.
