Can a nozzle provide the breakthrough indoor farming has been waiting for?

Horticulture Week ^ | May 3, 2018 | Gavin McEwan

[2ndDivisionVet]

A British company says it can greatly extend the range of crops grown in indoor growing formats beyond the established leafy greens and herbs.

Discussions on the potential of urban and indoor farming invariably mention the need to feed a growing global population, forecast to reach 10 billion by the middle of the century, against a backdrop of climate change and depleted land and other resources.

But so far, for technical and economic reasons, the movement has largely targeted leafy greens and herbs — relatively high-value but low-mass, low-calorie crops. Indeed, one successful London grower specialises in "micro-salads" sought by higher-end retailers and restaurants that, for all their merits, are unlikely to displace much conventional farming or address food supply in the developing world.

This may be about to change though, thanks to a technological breakthrough by a British company. West London-based Airponix says it has overcome an obstacle to growing more high-calorie crops, thanks to spray nozzles adapted from printers.

Aeroponics is a variant of hydroponic growing in which plants’ roots are exposed to a nutrient-rich mist within a chamber, rather than sitting in a circulating water-and-nutrient solution. Like other indoor growing technologies, aeroponics has so far found a market in hobby growing more readily than in commercial horticulture, with several UK suppliers offering variants on the format on a range of scales.

That said, aeroponics is also the basis of what is claimed to be the world's largest commercial indoor growing facility, run by AeroFarms in a former steel mill in New Jersey, USA, and employing its own multi-tiered variant of the technology in combination with LED lighting to produce up to 900 tonnes of fresh produce a year.

But this too grows only salads. What has so far restricted aeroponic growing to such crops, Airponix explains, is that the size of the droplets in the chamber causes them to coalesce, precipitate out of the air and form larger droplets on the roots, inhibiting the uptake of nutrients and encouraging the growth of wastefully long roots.

Nutrient-rich 'fogs'

To address this, Airponix has worked with a developer of piezoelectric inkjet technology to engineer print heads that can emit nutrient-rich "fogs" — a term that Airponix contrasts with the "mists" of conventional aeroponics — comprising droplets that can be greatly reduced in size to below 20 microns, and indeed optimised to the needs of the particular crop.

These print heads also require less energy than other fog-making methods, are highly reliable and easy to install or replace under field conditions, says Airponix.

This allows the technology to extend into growing soft fruits, grapes, brassicas, root crops and even the cereal staples of rice, wheat and maize. Airponix says its own small-scale potato-growing trials show typical yields are around 50 times greater per hectare per year than from conventional farming, without the expense of heavy machinery, diesel or crop-protection products. Rather than capital-intensive glasshouses, or tech-heavy enclosed controlled growing environments, the growing system can be housed in simple polytunnels.

Airponix chief executive Michael Ruggier says: "Trials of our breakthrough technology show that we can produce crops such as potatoes with lower production costs and higher quality, competing strongly against conventionally grown new baby potatoes."

He adds: "The potential cost of the system is very low and requires little energy to operate. Manual labour is also greatly reduced because harvesting is a simple, clean process and root crops don't need washing."

Ruggier co-founded the company in 2016 with John Prewer, now its technical director, who developed and patented an early form of aeroponic growing more than 40 years ago, while its horticulturist and operations manager Barry Robertson was previously head of controlled environment horticulture at the John Innes Centre.

The technology has already garnered awards, including being named the overall winner in the Rushlight Awards for novel, clean technologies in January.

A-frame units

Airponix has now equipped a 1,000sq m glasshouse in Norfolk with its A-framed potato-growing units for development, testing and demonstration, thanks to a half-million-pound loan from Centrica Innovations. The glasshouse incorporates further growth-enhancement techniques such as imparting an electrostatic charge on the droplets for better adherence to and absorbption by the plants’ leaves and roots. A smart, fully automated system, operated by a mobile phone app, is also being developed.

The aim initially is "to demonstrate the yield quantities and the costs associated so that next year Airponix will be in a position to licence the technology", says a company representative, adding that it will also provide samples of the first crop, due next month, to supermarket retailers for evaluation.

"The type of potatoes that Airponix can grow and harvest are unlike anything currently being sold anywhere and has huge potential in both the fresh-produce and snacks categories," he points out. The company also hopes that selling this year’s remaining crop will provide revenue to enable it to extend its own glasshouse space and growing facilities next year.

[T-Bone Texan]

My first thought was “How can this be used to grow pot?”

[ptsal]

Have the Dutch farmers and Rabobank endorsed the concept?

[FLT-bird]

Interesting and potentially useful in many places to have indoor farming. It will also be essential to master this if we are going to colonize the Moon, Mars etc etc.

[volunbeer]

The hydroponic set-up with tilapia is pretty neat and I expect we will see more of that in the future. Technology continues its march in just about every field of endeavor.

[Moonman62]

Added the mention “climate change” and every sane bs detector should ring loudly.

...

I know mine did.

And if this technology were really as good as claimed they’d be looking to quietly use it themselves, rather than doing press releases saying they are going to license it.

[woodbutcher1963]

There was a NH Cronicle show on about a month ago about a company in NH that was growing lettuce by the same/similar method. They can grow it a lot faster indoors than outside. Plus they grow it all year round. They stated that all their product was sold out to various restaurants in New England. It is called Lef- Farms.

http://www.wmur.com/article/tuesday-april-4th-lef/9213567

[trebb]

So spake the SecDef in "Independence Day" before the Pres in the movie fired the "It'll never work" weasel.....and people cheered......Not much progress was ever made in the world by those who concentrated on finding reasons why something would never work - always those who work hard to make it work coming up with the best stuff.....

Have a great day - unless you find it too tedious......

[imardmd1]

Oh! I get you regarding the sol system. But I didn't write my thesis clearly. What I meant was that overuse of soil through planting potatoes without renitrogenizing and sufficienr remineralizing exhausts the soil so that even peas and beans and clover won't grow on it profitably for some time. I'm no farmer, but my grandparents were dairy farmers with potatoes as a cash crop, and they took care of their land by using it properly. But back in and before the Great Depression days, the growers that used migrant pickers bought unused land throughout the Southern Tier of New York State, came in and exhausted the land, them left the used-up land without taking the hit for fallow years, leaving the poor soil to grow wild mustard and silvertop and ragweed, never leaving it even sown with cow-edible crops of hay or alfalfa.

On the other hand, after reading the notes on the aerosols generated acoustically, I thought this was a great way to grow nutritious red-skinned marble potatoes that have a high specific surface area, without using much real estate to do it.

While mulling it over, I remembered that fifty years ago I was engaged in designing and making erosion-resistant sonic nozzles for the paper-making industry to recover the sulfites from the mill liquor by evaporating the water from it.

I hot-pressed silicon carbide rings in graphite molds at about 2000 degC, then subsequently milled the ring ultrasonically with boron nitride slurry and sacrificial Hastelloy tool tips (B₄N grit is harder even than diamond paste). This formed the chamber which under high pressure flow developed cavitation in the gas and hence dispersion into droplets of the liquor injected into the flow.

These fabricated rings were then mounted in 430 Ti-stabilized stainless steel enveloping rings by heating the assembly of nested rings to fuse the glass frit powder placed between the outer SiC wall and the inner stainless ring wall, such that on cooling, the differential shrinkage brought the brittle carbide ring under such compression that it was impossible to break it under normal pressure generated by the ultrasonic generation while in use, and extremely resistant to chemical corrosion or solids wear by the hot sulfite liquor being dispersed by the nozzle (I hope this makes sense to you).

I don't see how the inkjet-activated mist generating orfice can remained unclogged and/or unworn in the kind of application and in the kind of volumes this article describes.

[miniTAX]

The dust bowl during the Great Depression was probably due more to a combination of financial, social and climatic problems (very frequent drought) rather than to the depletion of soils. Because if it’s due to the latter, it should have happened also in other parts of the world where there are much more population densities and intensive agriculture than in the US.

Soil depletion is one of the preferred myths of greenies, but like anything from them, it’s a dead wrong misconception. There is a simple index that demonstrates it is bunk : productivity per acre, which has increased year after year for decades, for each and every big crops (corn, wheat, potatoes). Even better (or worse for the malthusians’ lie), productivity per unit mass of fertilizer has also increased, showing that not only farmers are more skilled (not a scoop) but that soils are improving not depleted (by producing more per unit mass of fertilizer, but the atmospheric CO2 fertilization factor plays a big part too).

Your know-how in precision mechanics and materials is fascinating. I have zero doubt about your assessment of their mist generator wearing out.

[imardmd1]

Thank you for your lucid description of the status of growing good food. As I said, I am no farmer, but it is in my heritage and I grew up in small country towns with lots of rugged farm boys and girls in my classes. One thing I learned is that they are not easily misled by bullshooters.

But I see that the whole character of it has required changes from what it was in the mid-20th-century. The transition to electricity and the petroleum engine as energy sources have affected all of life, especially the chemistry of fertilizers and their production.

I hope that we leave a better world to our children than the one we entered.