We had a severe water shortage here in South Florida last year. Homeowners were not allowed to water their lawns but once a week for limited periods of time. My wife's vegetable garden was wilting and our fruit trees were dying.
I had installed a rain barrel system using two 55 gallon barrels earlier, along with an 8 panel solar system powering our master bedroom. It didn't take long to add a catch pan under the output of our AC condensate drain. I installed a twelve volt bilge pump, powered off the battery bank in the solar power system, with a float switch in the pan and piped the output back to the rain barrels with a length of garden hose.
The system provides about two and a half gallons of water per day depending on air temp and humidity.
We were running the AC unit anyway, so in essence we got free water for about $25 (bilge pump and switch).