You can earn $3 Million USD a year from one acre Florida Ag land if you grow giant pumpkins. Pumpkins make one gal (GGE) of methane for each 50 pounds of wet pumpkin. The biggest ingredient is water. You have to use hydroponics to deliver the water and increase fruit size. An acre will hold approximately 3200 pallets but 2700 is more reasonable to make room for navigation. Dills Atlantic Pumpkins routinely grow to 500 lbs but aim for 1000 lbs. There will be three or four harvests every year. You have to use plant grafting to make new plants. You'll grow 10,000 pumpkins every year. You'll harvest approx 30 fruit a day. You can reclaim the water, potassium and phosphate. This will produce 60,000 cubic feet of methane daily. QA work should produce more gas to optimize the reactions. This methane is first cleaned, stored in a large CNG tank and then fed into a Gas to Liquid (GtL) catalytic reactor ($2 million USD) which in turn will produce 30 - 50 barrels of synthetic gasoline or diesel fuels. This sells easily and you get tax deductions and RINS for each gallon. The remaining mash is fed to bugs to produce biodiesel fats and bio ammonia.
Biofuels need M&M's; Mass and Metabolism and pumpkins deliver. We can find a use for this car sized fruit if we look hard enough.