Hydroponics sustainability has been touted as one of the leading farming technologies to combat climate change. Its promise is to help reduce water usage, soil erosion, environmental damage, and species extinction caused by overexploitation and intensive farming. Supporters of indoor farming and controlled environment agriculture (CEA), all advocate for this rapidly advancing system within the indoor farming arena. It is quickly becoming the new most sustainable way to grow crops.
Let’s talk first about the term sustainable or sustainability. Sometimes when we talk about being sustainable we may actually mean something else like, organic, environmentally friendly, eco-friendly, green farming, or energy efficient. Not to say that these descriptions won’t also fit the definition of a particular hydroponic system design but many of the terms are intermixed or used incorrectly. The definition of sustainability is broad. A popular definition of Sustainability means, meeting our own needs without compromising the ability of future generations to meet their own needs or as an old proverb saying goes, “waste not want not“, meaning, If we don’t waste what we have, we’ll still have it in the future and will not lack (or want) it.
According to experts, the world is on the brink of its worst food crisis within the next 50 years. The global food industry is always searching for more sustainable and accessible ways to produce healthy food as locally as possible. Vertical farming methods, specifically with the use of Hydroponic systems, may provide that solution by maximizing output while simultaneously minimizing the use of space, soil, and other resources.
Hydroponics Sustainability: Environmental
Shipping produce great distances to their consumption destination is unsustainable. Hydroponics allows gardeners to grow locally. Growing closer to, or at, consumption destinations provides for less transportation costs and pollution.
Indoor hydroponic systems require a high level of energy consumption which generates a much higher carbon footprint than traditional agricultural farming. Additional renewable energy technologies need to be added to current hydroponics systems make them more energy efficient which is more sustainable.
The excessive use of chemicals in today’s agriculture with the help of machines reduces the fertility of the land, air, and water and is unsustainable. Hydroponic operations have less need for such treatments than field-grown crops. “In a well-maintained, well-integrated indoor horticulture practice, there are no pesticides or herbicides needed,” Much less than traditional agriculture.
The extreme clearing of land is done for animal agriculture, farming, and cattle raising is unsustainable. Almost 50,000 acres of forests are cleared by farmers and loggers per day worldwide, and over 10,000 football fields are destroyed each day in the Amazon forest alone! The results are habitat loss, amplification of greenhouse gases, disruption of water cycles, increased soil erosion, and excessive flooding. Excessive use of chemicals and the overuse of farming equipment machines exacerbate the situation and compound the potential for catastrophic environmental damage.
Hydroponic farming techniques use water infused with nutrients as a means of feeding plants at the root level instead of soil. This allows for much more precise delivery of specific nutrients at different stages of plant development and allows the farmer or home gardener to customize the nutrient solution for desired results.
Hydroponic systems use about 10 times less water than traditional field crop watering methods because the water in a hydroponic system is captured and reused in a closed-loop system, rather than allowed to run off and drain to the environment. This also saves the local waterways from being introduced to excessive amounts of waste nutrient water that has been known to cause local algae blooms in local streams, bays, and estuaries.
Some indoor hydroponic farms report using less than 1/2 gallon of water to grow one pound of lettuce. Compare that with the 16 gallons of water needed to produce one pound of lettuce with conventional farming techniques.
Additional water-saving technologies and methods to save water
- Recycle Plant Water– Most of the water taken up by plants root system gets transpired as part of their natural water cycle. Plants transpire which releases water vapor into the air. In a controlled environment, this water vapor gets removed through the ventilation system. High tech hydroponic systems use a condenser in their environmental control system to recover this water vapor from the air. The water is then pumped back into a reservoir to be reused in the automated watering system.
- Recycle Waste Water – Reusing wastewater is not on top of mind for most people when designing their hydroponic system. There are 2 types of wastewater, grey water, and black water. Greywater is wastewater from basins, baths, and showers. Blackwater is any wastewater that is contaminated with water discharged from a toilet. Blackwater recycling is often more practical since most buildings don’t separate waste streams. Fully treated and purified wastewater makes economic and environmental sense and is a valuable water-saving method, especially for use in drought areas and underdeveloped nations where freshwater supply is scarce.
- Rainwater Collection- Rainwater capture is a previously overlooked resource that is beginning to get more utilized in more indoor farms than ever before. Small farmers and hobbyists use rain barrels or cisterns to collect rainwater for use in their hydroponic system. Larger indoor farms capture rain runoff water in large ponds or reservoirs as a water supply for irrigation.
Hydroponics Sustainability: Economic
Enhanced plant yields
Hydroponic system plants are more densely spaced together compared to the size of land that would ordinarily be needed to grow the same number of plants in conventional farming. This allows hydroponic systems to produce a greater yield of fruits and vegetables within the same space. The ability to fully control the lighting, environment, nutrient balance and pH level give indoor farmers the ability to perfect the best crops in the shortest time frame with the least amount of waste.
Hydroponic systems come in a variety of designs and sizes including vertical and stacking systems that allow indoor farmers to grow the most amount of produce in the least amount of space.
Indoor hydroponic systems allow plants to grow almost anywhere in the world, all year round.
Properly set up smart technologies help make fewer mistakes and avoid loss of crops
- Environmental controls – Control the air temperature, circulation, temperature, and humidity.
- Pump timers – Control the timing of the water and nutrient flow
- Light timers –Control the light timing
- Automated nutrient supply – Automatically adds a series of nutrients to the purified water to balance a custom nutrient solution
- Automated water supply – Controls the water levels in each reservoir and adds accordingly
Hydroponics Sustainability: Social
Often the most overlooked aspect of sustainability. Most sustainable discussions often focus on the environmental or economic aspects of sustainability and as you can see here we were easily able to have enough information to review those discussions. However, it is important to address all three areas of sustainability to attain the most sustainable outcome. A popular definition of social sustainability is the process for creating sustainable successful places that promote wellbeing, by understanding what people need from the places they live and work. Social sustainability should combine the design of the physical world with the design of the social world. It should provide an environment to support social and cultural life, social amenities, systems for people to engage, and space for people to evolve and interact. Indoor hydroponic farm builders should take heed to this mantra as it is more of an enclosed interactive environment compared to traditional agriculture.
Even though hydroponics is currently one of the most sustainable ways to grow food, there are some drawbacks. Some experts describe a watery, artificial taste with some of the vegetables and herbs are grown hydroponically. The range of vegetables that can be grown hydroponically is fairly limited, but experimentation has this list growing regularly.
Due to the very nature of how hydroponics works, growing plants without soil, many proponents of the organic label have cried foul and claim hydroponics cannot be labeled USDA Organic. They reacted negatively to the National Organic Standards Board’s recent announcement to allow hydroponic farming operations to be certified USDA organic. Their argument is that hydroponic growing does not support soil health. This major detail is not only one of the key principles of their organic farming movement, but some would also say one of the most important contributing factors in reversing the effects of climate change.
So, currently, hydroponics is sustainable, considered by some to be organic, but not necessarily energy-efficient, and depending on the type of system and how it is run it may not even be eco or Earth-friendly. Yikes! Many hydroponic farms are sprouting up locally in abandoned warehouses and unused retail spaces in cities across the country. Local restaurants have even gone as far as to purchase complete turn-key hydroponic systems built inside a shipping container that they have delivered to reside right outside their back door. tall about farm to plate! This reuse of valuable real estate close to the produce retail destination is incredibly sustainable.