As of last Tuesday, water was flowing through all three aquaponic greenhouses at the Kingman Research Farm in Madbury, New Hampshire. The construction of the aquaponic greenhouses began in April of 2017 and construction of the research systems started in October of 2017; the commencement of operations in the third and final greenhouse this past week marks the completion of the facility.
The aquaponic greenhouse facility will allow students from various fields of study to get real experiences with farm work under controlled research conditions. The aquaponic greenhouse facility project’s principal investigator, Todd Guerdat, said these kinds of hands-on experiences will help students when they apply for jobs in the future.
“When we get out of school, two letters or three letters next to our name is not enough for us to get a job, you always want experience,” Guerdat said. “This is an opportunity to get real work experience… Not only [will students] know how the farm works, but [they] really understand the fundamentals behind the farm so that when it comes time to problem solve or to build something new, [they’re] valuable, [they] actually understand how things work.”
As a business model, aquaponics is relatively new within the past decade or so. According to Guerdat, however, ancient hieroglyphs depict Egyptians growing fish and plants together in a pond, much like the way that aquaponics functions.
Guerdat, an agricultural engineering assistant professor at the University of New Hampshire (UNH), said that aquaponics could be related to dairy farming in the sense that an animal is grown, a waste is produced, and that waste has to get collected, treated and utilized again.
“For us, we apply it to a hydroponic system, we’ve built our own fields, so an aquaponic greenhouse is recirculating aquaculture for food fish production coupled with hydroponic crop production, in this case lettuce, for food production, as well,” he said. “Aquaponics is nothing more than another version of integrated agriculture, and integrated agriculture takes the waste from one production process and utilizes it as a resource in another production process.”
Currently, the facility is working with tilapia as the species of fish used within the aquaculture aspect of the system, and lettuce as the crop produced through the hydroponic aspect of the system. Tilapia and lettuce grow the fastest for purposes of research according to Guerdat, so the facility will work with model systems like this one first, and then get increasingly more adventurous.
“This model is a benchmark,” Guerdat said. The facility is beginning to grow plants like strawberries at the moment, and eventually will be working with fruiting crops that will generate more money than a leafy crop like lettuce.
The benefit of an aquaponic facility, per Guerdat, is the monetization of waste treatment, meaning that they are making money off of waste from aquaculture, and they are creating a naturally derived nutrient source for plants which allows the facility to get closer to organic certification. Guerdat said that this is about as close as one can get to the equivalent of crop production in the fields.
“We don’t use soil, we are all in the water, so we take advantage of how plants take up nutrients,” he said.
In terms of sustainability, Guerdat said that from a nutrient standpoint, the aquaponic system is using more of nutrients in the entire production process than any other one type of production system out there.
“While we’ve not done the numbers yet because we aren’t quite at the optimized answer to this, we can say that we use more of our input nutrients than any other animal agriculture system out there, which is awesome,” he said. “We are wasting less nutrients, we are actually putting them into something [which] improves nutrient utilization efficiency, which is a huge sell from an environmental standpoint, but it’s also a huge sell from a business standpoint.”
The facilities manager of the project, Sean Fogarty, believes that this kind of system is a way to reduce negative impacts that agriculture can have on the environment.
“These sorts of systems mitigate a lot of the environmental damages that can happen due to other sort of agricultural practices where wastes are discharged into the environment and cause ecosystem problems down the line,” the first semester master’s student said.
Although the system is sustainable in some ways, Guerdat said that energy-wise, it is not always the most efficient.
“From an energy standpoint, if you were to take one step back and look at a greenhouse in February, then you would think ‘holy cow, that’s a boatload of energy, how is anything like this sustainable?’” Guerdat said. “But what’s cool is that we’ve done some research with the environmental engineering folks here at UNH and they do what’s called a life cycle assessment which looks at the big picture… and what we realized is that if we operate a fish farm and a hydroponic farm separately, we use a boatload of energy, if we operate the two together and then normalize everything… we actually consume less energy and less water and less nutrients all at the same time, so this coupled system is a way for us to move forward through integrated farming to reduce all of our requirements and inputs and still come out with the same amount of food.”
At the end of the day, Guerdat says that the system does use more energy, but his answer to anyone who questions the system is that it is only one piece to a much larger puzzle.
“We’re all in this together, and so we are focusing on the nutrients from an economic standpoint, for the purpose of producing food, but there’s still an energy component that has to come into this,” he said. “That’s where we then point to the other guys over in the engineering, power and energy world and say ‘alright, you guys come up with more sustainable ways to produce energy, we will come up with some more sustainable ways to utilize our nutrients.’ And if we put all that together, now what we have is a much-improved system overall.”
In addition to sustainability, Fogarty expects aquaponics to play an increasingly significant role in how we feed ourselves as a region because “it can be done at almost any scale depending on what the markets are, and people are really hungry for locally produced [fruits, vegetables] and meat, including fish, year-round, so this has the potential to provide that even in the off-season when other sorts of farms aren’t producing.”
Presently, the facility is producing 1,000 heads of lettuce a week and 100 pounds of fish a month. Guerdat said that traditionally, some of this food goes to the food bank. The amount of food produced, however, means that it is something that is sellable, and according to Guerdat, “it costs money to run the greenhouses.” He added that a lot of the food is getting sent over to the students who are actually growing it, meaning that it is being sent to dining services and it is being put into the dining halls.
Guerdat said that the new aquaponic research facility is providing a roadmap for environmental sustainability while also answering economic needs.
“We are minimizing our environmental impact and maximizing our likelihood for sustainability through economic evaluations of these types of processes… the big sell is being able to show that we can be environmentally conscious and economically sustainable at the same time,” he explained.