where should i invest in solar power to make the most money   who has the patents?

What sort of investment are you thinking of ?

Domestic solar power (and heating) have rather long payback times and
you would probably be better off doing something else.  Low-grade heat
schemes with large storage can be workable but obviously aren't for
everybody.

Solar power is so old that (20-year) patents should all be expired. 
But with the lunacy that is the current patent scheme I wouldn't bet
on it.

Buy stock in acompany that producecs them