Three honest ways to pay for it
There is no single right answer. The best path is the one that costs you the least over the full term for the cash flow you actually want.
Lowest lifetime cost
No interest, fastest payback, and the savings are yours from day one. The tradeoff is the largest up-front outlay.
Often $0 down
A fixed monthly payment in place of a lump sum, and you own the system. Bill savings help carry the payment.
On your tax bill
Repaid through municipal property tax, up to $50,000 over 20 years. Fixed rate, tied to the property.
Same endingYou own itAll three finish with a system that keeps producing long after it is paid off.
Only real differenceCash flow and total costCash wins on lifetime cost and payback but ties up capital. A loan or CEIP spreads it out so the utility money you were already spending goes toward ownership instead.
My job is to lay the real total cost of each path next to each other, not to steer you into whichever one pays me fastest.