Roots’ cooling technology allows US luxury cannabis producer to double yield and lower energy costs

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By Imelda Cotton - 
Roots Sustainable Agricultural Technologies ASX ROO cannabis yield Canndescent RTZO

Roots has increased the yield of dry cannabis flowers by up to 118% compared to uncooled crops from various strains.


A cooling system developed by Roots Sustainable Agricultural Technologies (ASX: ROO) has increased the yield of dry cannabis flowers by up to 118% at a premium production facility in Southern California.

The Israeli company installed its Root Zone Temperature Optimisation system into a climate-controlled greenhouse owned by luxury cannabis cultivator Canndescent to stabilise the roots of its cannabis plants at an optimal temperature of 21oC.

The recreational and medicinal cannabis producer customises its plant-growing environment by stage and strain, with flowers picked and trimmed by hand.

Ambient air temperatures within its greenhouse can reach up to 30oC, with outside temperatures topping 43oC.

In May, Canndescent paid Roots $28,000 to supply and install the RZTO system and achieved increases of between 30% and 118% during the US summer on cannabis strains of 400 and 200 cooled plants respectively utilising wet mattresses and fans within the greenhouse.

The system has helped the producer battle Southern California’s dry desert climate, where temperatures can fluctuate during the summer months between 20oC and 40oC.

Extreme heat can have detrimental impacts on cannabis production and crop quality.

Doubling yield

Roots chief executive officer Dr Sharon Devir was impressed with Canndescent’s results.

“These results verify the effectiveness of our root zone technology on greenhouse-grown cannabis,” she said.

“It allows growers to more than double their dry flower yield in certain strains to quickly generate a return on investment while lowering energy costs associated with traditional heating and cooling systems.”

Dr Devir said the results also reinforced the “uniqueness of our offering” within the highly competitive cannabis market and were consistent with those achieved by cannabis growers in North America and Israel.

Stabilising temperatures

Roots’ patented optimisation technology promotes growth, productivity and quality by stabilising a plant’s root zone temperature.

The system leverages the principles of ground source heat exchange using a network of closed-loop pipes.

The lower pipes are installed at a depth where soil temperature is stable and not affected by weather extremes, and the upper in the target crop’s root zone just below the soil surface.

Water flowing through the lower pipes is charged by the soil’s stable temperature.

The heated (or cooled) water is then pumped through the pipes installed in the root zone, where the heat (or cold) is discharged.

Dr Devir said the system can significantly increase yields and growing cycle planting options, while improving quality, mitigating extreme heat and cold stress.

It can also reduce energy consumption by stabilising and optimising root zone temperatures.

Demonstration greenhouse

Earlier this week, Roots signed a collaboration agreement with Perth-based ClearVue Technologies (ASX: CPV) to explore complementary sales opportunities within the growing greenhouse sector, including the construction of a world-first demonstration greenhouse in Israel.

Under the terms of the agreement, the companies will jointly pursue sales opportunities with new and existing clients, leveraging each other’s industry-leading technologies to bring a combined offering to the greenhouse market.

The planned demonstration greenhouse will utilise ClearVue’s energy-generating, photovoltaic, solar glazing glass panels to power Roots’ RZTO and Irrigation-by-Condensation technologies.

The off-grid structure will be designed, developed and constructed at Roots’ research hub in Israel and will be available to both companies for demonstrations and display purposes.

Roots will utilise the greenhouse year-round to conduct RZTO and IBC testing on various crops and plants.

IBC was launched in May 2018 to enable small and medium-scale farmers to grow food crops irrigated only from humidity in the air, and was specifically targeted to users in remote areas with water scarcity and quality issues and no access to grid electricity or irrigated water.

“This [greenhouse] collaboration will enable our customers to access a fully-integrated, self-sustaining solution which improves crop yield and quality, lowers operational costs and improves profitability for growers,” Dr Devir said.

Technology project

The companies have also agreed to collaborate on the deployment of Roots’ RTZO technology into a $1.6 million greenhouse being progressed by ClearVue at WA’s Murdoch University under a federal government Co-operative Research Centre Project grant.

The commercial-scale greenhouse will test the effectiveness of ClearVue’s PV glass technology to generate renewable energy and will be located close to other greenhouses within the university’s new agricultural precinct.

At midday, shares in Roots were 12.77% higher at $0.053, while shares in ClearVue were down 2.78% to $0.175.