There are numerous companies that make atmospheric water generators *safe to dri...

There are numerous companies that make atmospheric water generators safe to drink that are in some cases solar powered and some that require higher input power. There are some units on Amazon that can do 8 gallons per day [1] and you can drink the water. That might be sufficient for a really small greenhouse using drip irrigation. You could store excess water in tanks. There are much bigger units but the cost goes up exponentially. These folks [2][3] make some bigger units. Here is a station that does 400,000 liters per day [4] Here is a more detailed video that describes the process. [5] There are also some hobbyists on youtube that are making DIY solar powered atmospheric water generators. I think there may come a time that we will need all available options. AWG's, Desalination Plants, Rain Capture at very least. Here is a 20k liter/day unit. [6]