LettUs Grow

Food that’s grown in the air instead of soil could soon appear on plates in Britain and other parts of the world.

A new investment deal worth $1.8 million to build indoor farms uses technologies developed by a company called LettUs Grow, a Bristol, UK-based startup that designs irrigation and control technology for vertical farms.

The startup will partner with ECH Engineering, which manufactures controlled environment technology, traditionally in refrigeration, and urban agriculture experts from Grow Bristol. Bristol has made a name for itself as Britain’s greenest city.

The company is one of a number of startups in the fast-expanding area of indoor growing who are supplying farm management software, crop analysis and testing services, through to full indoor farm design and build.

A glimpse of the pilot aeroponics project in Bristol showing a variety of produce being tested using the system.

Following earlier seed funding, if you’ll pardon the expression, it’s now scaling up operations to produce its aeroponic system, which suspends plants in the air and feeds the roots via a nutrient-dense mist. This technique results in faster growth rates than conventional hydroponics.

“The nutrients we use are made with mineral salts, not chemicals,” co-founder and managing director of LettUs GrowCharlie Guy told The Fifth Estate.

“They’re formulated for the vegetative stage of growth in hydroponics and aeroponic systems and precisely balanced and manufactured for great results.

“In our system we reclaim and recycle most of our water and any nutrients not absorbed by the plants.  Due to this recapture and reuse, we use about 95 per cent less water than traditional field-based agriculture and 30 per cent less than typical hydroponics with our unique aeroponic technology.”

Since the plants are indoors, pest control is possible without pesticides and fungicides, making the production process organic. Previous trials have seen crop yield increases of over 70 per cent compared to conventional techniques for leafy greens, salads and herbs.

Yields and crop cycle times vary from crop to crop. The shortest is just five days for certain microgreens, to just over 30 days for head lettuce from seed.

A pilot project involving Grow Bristol involved an indoor hydroponic vertical farm that produced 100 kilograms of nutrient dense leafy greens every month without the use of pesticides and with minimal environmental impact. It tested over 50 crop varieties and sold the products to over 60 customers.

Having tested over 40 different varieties LettUs Grow’s core crops are: coriander (micro), fennel (micro), leek (micro), kale, pea shoots, sunflower shoots, radish, red cabbage, lettuce (many varieties), coriander, watercress, basil, and pak choi. “They’re our main crops, but we’re also growing rooting and fruit crops too (strawberries, spring onions and carrots, for example),” Guy says.

“We are expanding this facility in 2019 by over 10 times, to allow the testing of more and more crops and to expand our work into strawberries and root crops,” he adds.

Government funding

The $718,810 government funding is derived from the UK’s innovation agency, Innovate UK, and will be matched by $157,918 from other sources and research grants.

The grants came hot on the heels of the disruptive startup’s most recent investment round, where they raised $835,179 from ClearlySo, Europe’s leading impact investment bank, which has an extensive network of high-net-worth individual and institutional investors.

“Our investors see the value, both in terms of financial and environmental/social returns from tackling this systemic global problem. That’s why they got involved in LettUs Grow. LettUs Grow provides the technological innovation piece to the vertical smart farming movement that is currently trending rapidly in the urban context,” investment manager at ClearlySo Matias Wibowo says.

The company has ambitions to supply a rapidly growing global market for efficient and sustainable farming technology.

By 2050, humanity has to increase food production by 70 per cent to feed over 9 billion people without breaking the planet’s life-support systems, which would happen if present agricultural and food industry logistics trends continue. Aeroponics can help to address the colossal degree of waste that presently exists throughout the supply chain.

“The global agri-tech industry is very exciting right now, all stemming from the necessity to improve the economic and environmental sustainability of food production. We are fielding enquiries from all around the world from food producers and farmers who want to experience the benefits of our technology across a growing range of crops,” Charlie Guy says.

The environmental footprint

The Fifth Estate asked Charlie Guy about the environmental footprint of the technology and the energy used in a given system, compared to a soil based or hydroponic system.

He says that it depends on a number of factors, including choice of crop, choice of technology, retail route, geography, climate and season. “One of the key benefits of indoor growing, over traditional methods, is the massively reduced supply chain length. This cuts the carbon footprint of produce substantially.”

LettUs Grow are working on integrating indoor and vertical growing with renewable energy technologies to further reduce energy costs and the carbon footprint.

“Indoor, vertical growing generally acts as a substitute for imported produce,” Guy says, quoting studies claiming that CO2 reductions of up to 90 per cent are achievable by growing produce at its point of consumption using hydroponics, compared to the carbon cost of importing the same product from Europe.

He also refers to independent, academic studies into the startup’s technology that have shown that its patent-pending aeroponic technology can reduce the carbon cost of production against traditional hydroponic vertical farms by between 60 and 90 per cent.

But can the operation scale up? “Scale of operation is one of these determining factors and the vertical growing industry is still some way off the scale currently reached in glasshouse growing,” Guy says.

“The productivity increases demonstrated by LettUs Grow’s aeroponic technology represent another step-change in economic viability of farms. This enables smaller farms to deliver a return on investment up to 50 per cent faster than traditional hydroponic indoor farms.

“Energy and labour are two of the greatest operational costs of running an indoor farm and LettUs Grow are working on solutions to bring these two costs down substantially. LED lighting continues to fall in price and increase in efficiency and advanced automation processes are reducing labour costs further still.”

However, Guy says his system is “lighting agnostic”. “Anyone can use our system with any lighting. In fact, you can use our aeroponic technology without any lights, such as in glasshouses.”

To reduce costs, the company is investigating automation, not dissimilar to that found in giant Amazon warehouses. “We have designed our own automated farm management system called Ostara. It is breaking down barriers to entry for indoor farming and aeroponics. Aeroponic technology has historically been seen as complex and difficult to implement. Ostara makes aeroponics easy.”

The company plans to license its technology in the future. Watch out for indoor farms springing up near you in the not too distant future.

David Thorpe is the author of the book The One Planet Life and the forthcoming book One Planet Cities.

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  1. Hey Phil,
    Just read your comment! Aeroponics It’s coming to Brisbane
    Very soon. Our company will be producing it here, our main target market is apartment living people, as this system is made from fully sustainable material and uses the latest technology in solar power, and much more efficient and flexible like paper. Sourced o/s, not from China.
    Will be launching Shibui mid this year.

  2. Id be fascinated to see something like this take off in Australia. My moral compass is always a bit twitchy when I think about refrigerated trucks rumbling along bumpy Australian highways leaking refrigerant to deliver produce that is out of season in other states. Ive not thought about the full impact of vertical farms so would love to hear other’s thoughts.