Growing greener weed: How a B.C. pot producer is working to limit its environmental load

Canada is just one year away from legalizing recreational marijuana — and so far, national conversations about legal pot have mainly revolved around issues of safety and access.

But one British Columbia-based producer says it's time to bring the environment into the equation, because when it comes to sustainability weed actually isn't all that green.

Dan Sutton is the managing director of the B.C.-based Tantalus Labs, a major licensed producer of medical marijuana. He believes marijuana's environmental footprint is one of the industry's dirtiest secrets.

"About 90 per cent of the aggregate cannabis production is cultivated indoors, in bunkers and in basements," he tells Day 6 host Brent Bambury. 

"This requires a huge demand for electricity, and this results in a massive environmental footprint for the cannabis plant."

Large-scale indoor marijuana operations typically rely on heavy-duty artificial lighting — sometimes up to 24 hours a day, not to mention the costs associated with heating, air conditioning, and ventilation.

People were using old schools of thought, old principles. And we need to wake up to the fact that the future of cannabis is sun-grown.- Dan Sutton, Managing Director of Tantalus Labs

Cannabis is also a notoriously water-intensive crop. A single plant can consume up to 23 litres of water per day — almost twice as much as a wine-producing grape plant.

"Cannabis producers are using AC units, re-humidification, and a variety of other energy-intensive technologies to essentially borrow from Peter to pay Paul to reduce the symptoms of these energy-intensive indoor cultivation strategies," Sutton says.

All told, indoor marijuana cultivation consumes six times as much energy as the pharmaceutical industry and at least one per cent of all electricity consumption in the U.S.

But Sutton says it doesn't have to be that way.

Getting out of the warehouse

Legal marijuana producers probably won't be moving their cannabis crops into outdoor farmer's fields anytime soon, Sutton says.

"Today, the regulations of the ACMPR have to harmonize both safe and consistent cannabis production with a very stringent quality-assurance standard," he explains.

"As a result, indoor cultivation is the only methodology that's currently legislated."

But Sutton says it's still possible to make marijuana operations more environmentally-friendly — by taking cannabis out of the warehouse, and into a greenhouse.

"Greenhouses are a really great piece of infrastructure to cultivate cannabis with, because they combine the … environmental monitoring and control of an indoor environment with the ability to use natural sunlight to fuel the plant growth."

We rely on sunlight. And as a result, we save about 4600 kilograms of carbon output per kilo of cannabis plant produced.- Dan Sutton, Managing Director of Tantalus Labs

Sutton and his team at Tantalus Labs have fully embraced greenhouse technology at their own marijuana-growing facility in Maple Ridge, B.C.

Their "SunLab" facility, which has the capacity to grow 10,000 kilograms of cannabis per year, is one of the first purpose-built cannabis greenhouses in Canada.

And while the SunLab does use some artificial lighting in the shoulder seasons when the days are shorter, Sutton says it only amounts to roughly 3 per cent of the crops' light.

Ultimately, Sutton says the technology has enabled them to reduce their electricity demands by up to 90 per cent.

"It's a really interesting phenomenon," Sutton says.

"We've got a four-and-a-half-billion-year-old fusion reactor that hangs in our sky. And so in our environment, instead of relying on those lights, we rely on sunlight. And as a result, we save about 4600 kilograms of carbon output per kilo of cannabis plant produced."

The "hangover effect"

Sutton points to other established commercial cannabis producers like Aphria and Hydropothecary as proof that opting for greenhouse technology doesn't compromise product quality or consistency.

"This is greenhouse technology that's been mature for 15 or 20 years, and it continues to get better as greenhouses evolve."

Still, Sutton says, less than 20 per cent of Canada's licensed producers are currently using greenhouse technology. He attributes those low numbers to a "hangover effect" from decades of illegal, underground cultivation.

"A lot of these indoor production technologies have become really exciting to black market producers over the last 30 years, and the quality coming out of indoor producers is very high," he says.

"As a result, in the production infrastructure for the legal regime, people were using old schools of thought, old principles, and we need to wake up to the fact that the future of cannabis is sun-grown."

Sutton says cost needn't be a concern for producers who want to move beyond the warehouse model.

He says the SunLab's building costs were up to 80 per cent lower than the capital expenditures typically accrued by other major commercial producers.

"There are front-end savings, there are operational savings. The economic argument for greenhouse cannabis cultivation is substantial, and very well-grounded in logic."

To hear the full interview with Dan Sutton, download our podcast or click the 'Listen' button at the top of this text.