Win, win, win, win, win if you ask me.
However, a lease means if you sell and the Buyer doesn't want the lease - you fork over money to have them removed and the leasing company compensated. Oh and by the way, don't look for the 30% tax credit, quarterly SREC checks, and credit with the electric company because that goes to the leasing company not you.
Leasing does not make sense in my opinion...
p.s. I also installed geothermal heating and cooling - best investment I ever made..
If you want it do it and worry about the sale later.