Energy And Sustainability Implications Of Aquaponics

Calculating energy usage is difficult, especially when you are comparing conventional farming with all its energy inputs (energy to make chemical fertilizers, pesticides and herbicides; energy to apply these; fuel for tractors for plowing, cultivating, spreading herbicides and pesticides; and so on) to aquaponics farming (whose energy inputs are electricity and the energy required to make the fish food). But a thumbnail comparison of energy usage for our original HD systems that were built in 2007 as energy-saving adaptations from UVI’s system design is around 70% less than a conventional farm for the same vegetable production.

(Below) Our Energy Future graphic, from oneinabillionblog.com (thanks!).

This was only our first energy-saving design modification; our newer LD systems use around 92% less energy than a conventional farm does, because one of the things they’re designed to do is grow a maximum amount of vegetables using a minimum amount of fish. This includes the energy required for the fish production, a produce item the conventional vegetable farm does not have. All energy used is electrical, so alternate energy systems such as solar, wind, and hydroelectric can be used to fully power this farm.

I am certain that some people reading this will gasp at my saying “minimum amount of fish” in the previous paragraph. Yes, a minimum amount of fish! Why would you want to grow a minimum amount of fish? Because the fish are a net loss item, except under certain very specific circumstances. Please see the discussion about “LD versus HD systems” in the Fish Category for reasons why this is the case.

Aquaponics is the only way we know (other than using draft animals or humans for power) to farm without requiring oil. When the cost of oil goes up, market forces will unavoidably drive the cost for alternate energy systems down, making them more affordable (after an initial spike in prices caused by short supply). LD aquaponics and similar systems will become the standard for the farmer, because it will be too expensive to farm with oil. We will see more aquaponics farms and other alternate farming systems powered by wind, solar, and private hydroelectric systems.

Add in the rising cost of chemical fertilizer (the manufacture of which is incredibly energy-intensive; to find out more, purchase a book called The Alchemy of Air, which is the history of ammonium nitrate. It’s fascinating!), and at some point, organic produce from aquaponics systems and other energy-efficient farming systems will be the only thing on the market because it costs the same or less to grow than conventionally-farmed produce. Most consumers will switch to organic anyway when the price difference is minimal because the benefits are clear.

Many people mistakenly think “Organic soil-based agriculture is sustainable, and the way to go; why do you need to mess with aquaponics at all?” When you are talking about commercial scale organic agriculture (not someone raising vegetables in the back yard with a spade and a rake), then organic agriculture uses just as much petrochemical energy as conventional agriculture, and is no more sustainable! Why? Where the conventional farmer buys energy-intensive chemical fertilizers and spreads them on his fields, the organic farmer uses just as much petrochemical energy on his diesel-powered compost shredder and spreader, on diesel-fueled transportation to bring in manure and other compost components he doesn’t grow on his own land, and in the tractor he uses to plant and plow in cover crops to enrich the soil. Organic agriculture makes healthy food for us, but it is NOT sustainable!!! How much clearer can we be about this?

The bottom line is: Aquaponics is the number one sustainable candidate to grow our food when oil becomes too expensive to burn in tractors on organic farms and make fertilizer with. And we better start figuring out how to maximize aquaponic production and efficiency now, because many estimates show that without chemical fertilizer and cheap plentiful oil, world food production will be half (or less) what it currently is.