Ground mounted solar provides for the best production of electricity, runs 25%+ cooler, often times you get a usable covered area for parking and/or storage.

Solar panels on a residential roof has many challenges.  They are more dangerous to install avoiding personal liabilities for the home owner, solar panels do not perform as well due to trapped heat between panels and roof and when you have to replace your roof due to wind or hail damage you have to pay to remove solar - replace your roof and then pay to re-install your solar system and finally solar is a 30-50 year asset when you penetrate your roof tens upon tens of times your roof will end up leaking!