If you are constructing a new sustainable home that is off-grid (zero-energy), it should definitely qualify as an EEM, an Energy Efficient Mortgage.
An Energy Efficient Mortgage in Florida will allow you to stretch the housing debt-to-income ratio and the total debt-to-income ratio by two percentage points.As far as particular lenders go, I cannot tell you which lenders are currently participating in EEM's in Florida (I am located in Texas).
However, I can refer you someone locally who can help you. Contact Matt Ross at 941-376-8484 or by email at firstname.lastname@example.org. His company offers energy consulting services and provides energy efficient building products to the construction industry.
You can find out more about EEM's in my newly released book "How to Lower Home Energy Bills: From A to Z", available at amazon.com, and also, at the Department of Energy's Home Energy Savers website (here).
You will also want to visit the Appraisal Institute's website (here) and obtain Form 820.01. Form 820.01 helps to evaluate and substantiate all aspects of your home, particularly those that are energy efficient, such as a solar energy system. This will ensure that all the energy efficient aspects of your home are taken into consideration "value-wise" should you decide to sell your home at a later date.