Being a hydroponic enthusiast myself I have always dreamt of designing my own hydroponic system. Although most parts in the hydroponic system design are technical, it’s fun and also challenges your creativity at some points. So, here are some key points that you should take care of while you build your own energy-efficient hydroponic system.
One thing very important is to understand the dynamic relationship between food energy and water systems. Today we are going to focus on the efficient utilization of one of the technologies that address this balance and that is Hydroponics.
Hydroponics may be defined as the science of growing plants in water and without soil. A nutrient solution that contains the essential elements needed for optimum growth and development is delivered directly to the plant via the grow media. Hydroponic crop production is used widely throughout the US and the entire world.
It has some advantages over other indoor crop production systems. There are typically lower upfront costs and setup times, greater water use efficiency, and a higher level of control over the crop nutrient program.
There are many ways to set up a hydroponic system, but they can be categorized in a general way into two groups, depending on how the plants are supported.
Solid media-based systems use a variety of inert materials to give the plants the means to support themselves. Water-only based systems use mechanical means to support the plant. Some of the more common types of systems that use mechanical support include Nutrient Film Technique or NFT, Ebb and Flow benches and trays, and Raft or Floating systems.
Energy efficiency is a key parameter when selecting and designing a hydroponic system that will meet your needs. However, you could build the most energy-efficient hydroponic system on the planet, but if it doesn’t provide a healthy plant environment and good growth, it won’t succeed.
So, what is the key point to keep in mind while building your own hydroponic system at home?
Optimize Crop Production
You should focus on optimizing crop production and not just increasing energy efficiency while building your own energy efficiency hydroponic system. The essential elements in designing an energy efficiency system are pumping, aeration, filtering, and space optimization.
Now, because hydroponic systems are water-driven, some amount of water movement or delivery to the plant roots is required. It is important to minimize the number of pumping stations you need for the system to operate properly.
Handling Water Pumps
Ideally, pumping the water once and allowing gravity to move it through the system leads to higher efficiency and an added bonus of minimizing failure points in the system. This is the primary reason that people who build their own systems at home mostly prefer NFT as it uses gravity to deliver nutrients to all plants.
Hydroponic water holding tanks should be the lowest point in the system, and water should be pumped from there to the plants. In a recirculating system, the returned water should be allowed to flow by gravity back to the holding tank for example in a continuous flow solution culture system.
Also Read “How to Start Hydroponic Seeds”
Low Operating Pressure
We need to keep the operating pressure as low as possible without sacrificing watering uniformity by using large supply mains and sub-mains. Also, it is imperative to keep the orifice size from the sub-main to the crop as large as possible to minimize pressure loss. This will lead to lower clogging and encourage yields in addition to reducing the maintenance cost.
Reducing Pumping Time
While designing an NFT system on your own, consider putting the pump on a cycle timer so that it will turn on and off several times per hour. This will reduce the pumping time by approximately 50%, a huge amount of electricity cost can be saved this way. For the raft or floating systems, the water stays in the shallow pond, but it should be recirculating within the pond at a slow rate under low pressure.
Optimize Oxygen Supply
Plant roots need oxygen to respire and grow strong. Oxygen plays an important role and you need to consider the flow while structuring your hydroponic system. Roots should be intermittently exposed to fresh air for better growth.
In a solid-metal based system, you can achieve good aeration by giving water to the system at regular time intervals. You have to keep in mind the relative humidity, temperature and size of the crop, and also the characteristics of your grow media before you set the water pumping timer.
Control Irrigation Cycles
Managing the irrigation cycles properly, so that only five to ten per cent of the water being applied eventually leaches through the block or pipe will also save energy, water, and nutrients.
With water-based hydroponic systems, this is accomplished by allowing it to spill over a filter, spillway, or flowing quickly past the roots as happens in NFT. With raft systems, supplying air via air stones in the water is important to maintain oxygen levels.
Designing the aeration system to take advantage of stirring that will occur when flowing back to the holding tank is a good way to minimize energy use for aeration.
If you are thinking of constructing a recirculating hydroponic system, then you need to keep in mind that they need filtration to remove solid particles suspended in the pipeline. For non-recirculating systems like the static solution culture filtration requirements can be checked as per the impurity concentration of the water or the PPM.
If the water you are using is hard water then you may require more frequent filtration.
Large-sized filters require less energy and reduce the water pressure less than smaller size filters that process the same amount of water. Also, disc filters and sand filters require less frequent cleanings than screen filters For recirculating systems, the number of suspended solids can be significant and can contribute to the spread of root pathogens.
So, good filtration is important. You can also use low energy filtration techniques for your home hydroponic design which include spillway screens, settling basins, and sand filters.
Maximizing Space Utilization
Maximizing the use of available growing space conserves energy because the yields are higher per square foot without increasing the energy input.
It also helps to concentrate resources on a smaller area for example the temperature controlling light and cooling when needed for a smaller region will consume lesser energy.
There are several hydroponic systems where a high ratio of growing space to floor space can be achieved. Ebb and flow hydroponic benches and raft systems can occupy over 95% of the floor space because the crop can easily be moved out of a production row, and into a section of the greenhouse where the planting and harvesting can occur.
Spacing the crop out as it grows, can also maximize space utilization.
These are all the tips that I have gained through my research and experience in this field.
Do remember that Growing food in ways that use less energy, water, and fertilizer per unit of food produced, is a way to help everyone with sustainability and since there is a cost to all these things as well, it can only help your bottom line to consider ways to use less and grow more.