Water scarcity is currently affecting an increasing number of countries. In recent years, droughts have begun to affect areas historically untouched by such issues. Growing concern arises for agriculture, and new technological solutions focused on water-saving have been increasingly sought. Hydroponic cultivation in greenhouses is considered one of the most advanced solutions, as it ensures very low water consumption. However, the internal climate must be controlled. In particular, due to global warming, greenhouses more frequently require both heating and cooling. In this paper, a study is proposed on an advanced Atmospheric Water Generator (AWG) linked to a greenhouse to provide water and cooling. The machine is a real-world system capable of extracting water from air through a reverse cycle, simultaneously, providing dry and cooled air and a heat source with the same energy consumption. This paper presents, for the first time, a study of the energy and water cycle in a greenhouse coupled with the aforementioned machine, using dynamic models tuned with real data. Results give that, during summertime, the AWG can recover, averagely, 158 L/day, while maintaining the greenhouse internal conditions inside the desired range.