Growing cannabis the energy-efficient way

As the medical and recreational cannabis industries grow, Ontario producers have a big opportunity to increase profits. Doing it successfully in this fast-paced and competitive sector requires making energy efficiency a priority.
 
The energy it takes to power lighting, heating, pumps and ventilation for growing cannabis all adds up. Producing one pound of cannabis takes about 2,000 kWh - around what an average Canadian household uses over two and a half months. In fact, experts estimate that energy makes up roughly 20 to 50 per cent of the total production cost.
  
Luckily, there are plenty of opportunities for cannabis producers to find energy savings.

The power of energy monitoring

For Ontario's Canopy Growth Corporation, energy efficiency has become a competitive advantage.
 
"The cannabis industry is growing incredibly fast and it's becoming increasingly competitive," says Hilary Black, the company's director of patient education and advocacy. "As demand grows, we need more infrastructure and we use more energy. It's important for us to prioritize sustainability, while also keeping our operating costs down. That's why we consider energy efficiency throughout our operations."

Click below to watch the short video of how Ontario cannabis grower saves money.

It all started with prioritizing energy management, including implementing stronger energy monitoring. Now, the Ontario grower uses systems to collect detailed energy use, so it has a better picture of where and when it is using the most electricity. This allows the company to continually improve its design as it expands its facilities.
 
Along with regularly reviewing your energy usage data through your local hydro company, think about getting a comprehensive energy audit.

Once you have the tools in place to gather data, set metrics to measure for your operations and goals for your energy consumption. It may even prove worthwhile to hire your own energy manager to focus on finding savings and making the right decisions about upgrades based on how and when you're using energy.

A bright way to save

Like flowers and vegetable growers, cannabis operations have significant lighting needs.
 
Growing cannabis can require up to 18 to 20 hours of lighting per day, accounting for as much as 70 per cent of a producer's energy costs. To put it in perspective, vegetable growers typically keep their lights on for just eight or nine hours per day.
 
Greenhouse operators growing produce and flowers have historically used high-pressure sodium lights to help mimic sunlight during the colder, darker months. However, LED lighting is much more efficient, using up to 50 per cent less energy than high-pressure sodium lights.
  
LED lighting also lasts between five to 10 times longer than high-pressure sodium, cutting down on the costs to replace equipment. In many cases, greenhouse operators who invest in energy-efficient LED lighting see a payback within two to three years.
 
Canopy Growth made the switch to LED lighting, allowing it to increase its growing footprint without increased electricity costs. Using more efficient lighting allowed the company to introduce night shifts, so it could continue its operations when electricity costs are typically lower because demand is lower.

More efficiency, more control

LEDs also allow for greater lighting control, which may lead to higher yields. Growers can customize spectral light for the crop or growth stage. For example, a grower may find that more blue light than red light at a certain stage improves quality. LEDs allow for that control.
 
In the case of cannabis, the plants require a different intensity of light at different growing stages. More control over the type of lighting at every growth stage may help cut down on the effort of moving plants or lighting sources around.
 
One LED lighting manufacturer, Lumigrow, even estimates that its "precision" lighting allows growers to cut costs by 50 per cent and even control plant properties by controlling the ratios of light. LEDs also run cooler than alternative lighting sources, so growers can place them closer to plants, which may help improve crop yield.

Getting heat and humidity in hand

Reducing the heat that comes from lighting also helps growers manage humidity levels better and reduce the load on their HVAC equipment - meaning even more potential energy savings.
 
Dehumidification, which requires mechanical cooling, is crucial for cannabis growers to avoid mold and mildew which requires mechanical cooling, and like lighting needs, that can drive up energy use. Traditional HVAC systems typically bring in outdoor air to save on cooling the ambient air. This isn't ideal for cannabis growers, though, since introducing outdoor air into a controlled environment can also mean introducing pests and contaminants or causing mildew and disease. Cannabis growers also often inject CO₂ into their growing environments, and introducing outdoor air may throw off those elevated levels.
 
For these reasons, some growers opt for rooftop HVAC units, since they're designed to reduce the use of outdoor air. However, there are alternatives.

Smaller growers with between 4,000 and 6,000 square feet of canopy may want to consider high-efficiency split ductless air conditioning and heat pump units. By design, these systems use less fan energy than rooftop units since they're smaller. They're best for smaller operations, but if needed, multiple units can be installed for more capacity.

Keep in mind that both rooftop systems and split ductless systems require separate dehumidification units. For smaller growers, portable in-room dehumidifiers can help maintain the ideal humidity levels, too. However, dehumidifiers can add heat to the space and contribute to cooling costs.
 
Larger growers (with more than 6,000 square feet of canopy) may potentially find more cost savings with a chilled water system. In this system, chilled water in coils circulates and removes heat from the building before returning to a chiller to cool again. In a chilled water system, you can slow the fan speed and reduce the water temperature for better heat removal, without a separate dehumidifier.

Start your energy-efficiency journey

Whichever upgrades you take on first, remember that as more growers enter Ontario's cannabis market, saving on energy is ultimately a competitive advantage. Whether you're taking on energy-efficient lighting projects, upgrading your heating and cooling system or adding an energy manager to your team, saving energy will only help you grow.

Source and Photo Courtesy of Save on energy

Source: Save on energy