Today’s topic is a little complex, as when it comes to DWC Hydroponics; the cost dynamics can vary a lot depending upon the way one chooses to implement this technology.
Unlike an NFT, or Bato Buckets, or Vertical tower system which is pretty consistent in terms of equipment requirements and costs (choosing round vs angular shapes for NFT Channels or Vertical Towers may not have significant impact on input cost), a DWC system, offers a multitude of options when it comes to choice of structural design and layout. Different options can lead to a wide variation in costs.
This article assumes that the reader is aware of the basic concepts of Deep Water Culture or DWC. Similar cost dynamics will apply for ‘Kratky’ method of Hydroponics (barring the cost towards Air Pumps).
Choice of DWC Structure:
The following is not a scientific classification, but for a layman’s understanding, we will group the multitude of DWC structures into three classes.
- Tray only DWC system – as the name implies, this system does not contain any lid. It only uses a tray. This kind of system is primarily utilized for growing different varieties of grass like fresh green fodder for dairy animals or wheat grass for juice manufacturers for example.
A DWC hydroponic fodder tray may cost you between ₹600 to ₹800 per sq M.
- DWC trays with floating lids – in this kind of system, the bottom tray stores the nutrient solution. The top lid floats on top of the nutrient solution. It is the top lid that supports the crops. The roots of the plants are always immersed in the Nutrient Solution.
- DWC trays with fixed lids – in this system the lid remains fix at the top of the tray (instead of floating over the nutrient solution). As the nutrient level decreases in the tray, the roots grow downwards in order to be able to continue to draw the nutrients. This will leave the upper part of roots in the air (using which plant can draw Oxygen) and the lower part in water (using which plant can draw water and nutrients). If one stops to Oxygenate the nutrient solution in such a system, it is akin to ‘Kratky’ method of Hydroponics.
DWC trays with lids (floating or fixed) may cost you between ₹1,400 to ₹1,600 per sq M.
Grow Area inside 1 Acre:
Having opted for one of the above three set-ups, one needs to decide how many trays/units one can fit in an area of 1 Acre. For this calculation, we will go back to our last week’s article about setting up an NFT Hydroponics farm in 1 Acre. From that article, we will work with 29 growing columns of 1 m each. However, unlike in NFT, we are not restricted by the standard size of NFT channels. Thus, instead of 48 m of row length, we can use, let us say, 56 meters (leaving 2 m on either end).
This gives us an approximate growing area of 1,624 sq M (=29×56). One can increase the growing area by reducing the generous spacing between consecutive columns (which we have kept at 1m to enable a couple of persons to be able to walk through / work together). However, to maintain consistency in this series, we will work with an inter-column spacing of 1 m.
DWC Structure cost for 1 Acre:
Using the above data, the DWC tray structure may cost between 10 L to 13 L for growing fodder and between 23 L to 26 L for growing greens and vegetables.
Depending upon the set-up type, you may or may not need to spend on net-pots, holding plugs, plumbing, and air-pumps. But, you will still incur cost towards the elevated stands to support these trays, labor, and service charges of the agency that does the set-up. To maintain consistency, let us keep this number at 10 L like in the NFT example (Yes, cost of plumbing will come down, but cost towards stands will increase owing to larger area – row length of 56 against 48 – and more strength needed to support extra weight of trays and in-situ nutrient solution).
Thus, overall a DWC tray based Hydroponic set-up in 1 Acre can cost approx 35 L for the DWC structure set-up
As you would have noticed, the major cost factor is DWC trays. One can try to reduce this by looking at alternative options. I had tried to address a similar query sometime back. You can find the same here.
As clarified in last week’s cost, PN that:-
- This does not include cost towards the outer structure that we had covered here.
- This does not include the cost towards automation and nutrient supply system which we will cover at a later date.
- The above is an average case scenario; these will differ from cases to case and site to site.
- In case you have some factual info from any running projects, please do share and we will be happy to include it here (and correct any mistakes in our data) with due credits to you.
Gaurav is an entrepreneur whose first Start-up was focused on providing services to patients suffering from Chronic Diseases. While researching about the causes of lifestyle diseases and the ways to reduce their incidence, he chanced upon the idea of growing healthy and nutritious food using advanced farming techniques.
He founded CityGreens with a mission to enable City Dwellers to access Safe, Healthy and Fresh food.