Does growing plants hydroponically save water? Is it more efficient, cost effective and water smart during droughts?
Against typical field agriculture and horticultural techniques yes.
One test they did grow a field of plants, and also a hydroponic system. The Hydroponic system out performed the soil system and would have used a fair bit of water, but produced more. Because the test was to see if it was water saving they weighed the produce against the amount of water used. To produce traditional crops in soil, it took 80 litres of water for 1 kg of vegetable matter. THe Hydroponic system used 3litres per kilo of vegetable matter. THats saving 97% in water usage. Pretty good huh!