Global agriculture accounts for 70% of freshwater consumption. CEA responds to this challenge through the adoption of alternative irrigation technologies such as hydroponics and aeroponics which offer sustainable soilless solutions for reduced water consumption in the growing process. Dickson Despommier, the de facto godfather of vertical farming has always championed hydroponic irrigation, claiming that “hydroponic systems use 60-70% less water than traditional outdoor agriculture”. More recent developments in hydroponics and aeroponics alike, put that figure closer to 90%. But how would you go about calculating that?
There are various ways of measuring water usage in the irrigation process. For our own metrics, we measure the amount of water required per kg of produce. From several years of harvest data, we know exactly how much we can grow and how long it takes. Pea shoots for example, take just seven days under light to grow. We also know how much water these pea shoots need in the farm and the total volume our benches can hold. By considering that some of the water is either soaked up by the substrate, lost to evaporation or even used up by the crops, we can estimate how much water needs replacing each day. With all this data we can easily work out how many litres of water are needed for each kg of pea shoots.
By cross-referencing our own water usage with that used for growing outdoor tomatoes in California and outdoor lettuces in both Arizona and Spain, we found that our hydroponic system does indeed require 70% less water per kg of produce.
Hydroponic systems use 60-70% less water than traditional outdoor agriculture.
Our existing irrigation infrastructure is a Closed Loop system. Simply put, this means that we have taken steps to re-use as much water as possible. While it sounds relatively straightforward, to safely reuse water, the old or dirty water in the system needs to be ‘cleaned’ before it can be reused again. To achieve this we use the most efficient irrigation systems available complimented by some savvy filtration technologies which are designed to clean water without needing chemicals and improve the overall quality of the water while doing so. Therefore we can make sure that every millilitre of water is rid of nasty microorganisms and is safely used, recycled and reused in one big loop!