There’s a few ambitious Australian outfits spruiking the benefits of indoor hydronic farming but one company says theirs is the first to do it on a commercial scale.
The company, Sprout Stack, which won the business leadership category at last week’s Green Globe awards, is using abandoned shipping containers to grow chemical-free vegetables in a hydroponic system that is 95 per cent more water efficient than traditional farming and uses 80 per cent less fertiliser.
It also uses solar energy where possible to power its operations.
Vegetables are grown under controlled conditions, harvested within one to four weeks, and delivered straight to grocery stores to be sold.
At the moment, the company is selling its product to retailers such as Harris Farm and Harbord Growers Market.
The company is growing its hydroponic vegetables at its indoor farm in Brookvale on Sydney’s northern beaches with a team of about 15. Chief executive officer Hugh McGilligan says scaling up operations is next on the agenda but the company is still working on a blueprint to show investors how it will do this.
The company is currently backed by one “patient” private investor but it will be looking for other investors as it progresses to its next stage of growth.
Eventually, it sees itself expanding internationally with investors from Asia taking interest in the company. McGilligan says this could still be a while off and the plan is to grow in Australia first.
How it all started
The Sydney-based startup, founded by an agronomist and an electrical engineer, started out with a vision to bring leafy greens to rural communities where fresh produce is hard to come by.
The idea was to create a distributed network of the shipping container farms where there’s plenty of sun for solar power but limited water for irrigation.
The vision has since evolved but its potential is certainly biggest in water-poor and inclement environments, as well as areas with limited land resources.
Starting in 2016, the founders spent about 18 months getting the production right. McGilligan says this was no walk in the park.
“It’s actually quite hard to grow vegetables indoors.”
How the farms work
Not only are the shipping containers portable but the perfect environments for controlled indoor farming, McGilligan told The Fifth Estate.
Shipping container are stripped and fitted out with multiple stacks of trays for growing seedlings, which are filled with a coconut husk byproduct from commercial coconut production. McGilligan says it has no nutritional value but it provides a structure for plant roots to grow.
There are LED lights above each tray and a pump system that floods the trays with a hydroponic solution between one and four times a day.
McGilligan says the tricky part is getting the “growth algorithm” right for each plant – that is, the right temperature, nutrients, light, and CO2 quantity. These formulas are the company’s proprietary information.
The end result is a near closed-loop system, even reusing waste material as a medium for growing mushrooms.
Sitting behind the hardware is a technology stack that controls the farms’ systems automatically. In the future the plan is to leverage machine learning so that the farms can adjust the conditions automatically according to how well the plants are growing – adding a little more water or lowering the temperature as necessary.
The farms can grow “pretty much anything” – strawberries, herbs, kale – but at this stage the focus has been on leafy greens because the fast growth makes them more economically viable.
It’s not a perfect figure but McGilligan says the farms are capable of outputting an equivalent of about one hectare of traditional farmland.
This is made possible by stacking the hydronic beds. McGilligan says each container produces several thousand units of produce at one time.
People are ready for urban farming
The response to the company’s system has been “universally positive”. McGilligan suspects this is because people are starting to think more about the provenance of their food.
Part of the company’s mission is to bring people closer to the means of production – something that he believes we’re missing in the modern world.
“What we are combating is the disconnect between food and the means of food production.”
Nutritional value of fresh produce “falls off a cliff” during the week it takes to get from harvest to stores
Indoor hydroponic farming under LED lights is big overseas but in its infancy in Australia, but with our cities set to swell in coming decades McGilligan says we’ll have no choice but to rethink how we produce fresh food.
He says existing agriculture systems are already “pretty strained” with the situation expected to worsen as populations grow.
With normal agriculture systems, it takes a week to get produce from paddock to plate. But with indoor farming techniques, it’s possible to harvest one day and deliver fresh produce the next morning.
Not only does this lighten the carbon footprint of transporting goods around, this fast turnaround means more nutritious and tasty produce.
McGilligan says the nutritional value of fresh produce “falls off a cliff” during the week it takes to get from harvest to stores. He claims the company’s product is around 50 per cent more nutritious than traditional produce.
Much of the flavour disappears during the week long journey, he adds.
He doesn’t see the company’s methods as a replacement to traditional farming but a complementary source of production.
Triple bottom line sustainability
The company is committed to triple bottom line sustainability, with profitability expected to come with scale.
The company is also committed to bringing the community along for the ride through a school education program and employing staff from disadvantaged backgrounds.
He says the energy use is still “quite high” and “not where we want it to be” but the plan is to leverage solar power as part of its expansion.