By Walter Stark
A 2015 Gallup poll found that 58% of Americans believe marijuana should be legal in the United States. Considering that in 1969, just 12% of Americans held this view, it’s fair to say the tide is turning for the marijuana legalization movement.
That’s good news for cannabis growers; however, the industry’s high energy consumption is already of great concern to utilities, municipalities and environmentally-conscious Americans. Research indicates marijuana growers are responsible for 1% of the country’s total electricity usage. With more commercial grow facilities starting, this percentage is expected to rise accordingly, leading utilities and municipalities to caution growers that continuing this trend could have serious repercussions.
For growers, there are several incentives for transitioning to more sustainable energy practices. Energy-efficient operations will not only cultivate a more positive image with the American public, but they will also reduce their operating costs and avoid future conflicts when government agencies and utilities clamp down on energy consumption.
Understanding the full scope of this problem is imperative for proactive cannabis growers who want success for their own businesses and for the broader industry.
A Closer Look
Although 1% of the nation’s total consumed energy might not sound like a lot, it’s the amount of energy needed to power 1.7 million American homes, based on data reported in The Carbon Footprint of Indoor Cannabis Production, by Evan Mills, Ph.D., a staff scientist at Lawrence Berkeley National Laboratory.
At the regional level, the Northwest Power and Conservation Council projects that if the current rate of energy consumption by cannabis growers in the Northwestern states continues, it will double from 130 megawatts in 2015 to 237 megawatts in 2035. This calculation was based on the projected increase of Americans’ use of marijuana.
To gain some perspective for how things look on a state level, consider Colorado, which legalized marijuana in 2012. By 2014, data from Xcel Energy officials indicated that grow facilities in the state had consumed 200 million kilowatt-hours (kwh) of electricity. In Denver, where the majority of the state’s grow facilities are located, the 354 grow facilities in operation at that time were tracked at using 121 million kwh — a significant increase from the 2012 figure of 86 million kwh for the 351 facilities operating that year. By 2014, Denver grow facilities were responsible for 2% of the city’s electricity consumption. As of 2015, Colorado had more than 1,200 licensed grow facilities, which were responsible for more than 50% of the increased energy demand across the state, according to a Bloomberg News story by Jennifer Oldham.
Here are some other statistics projecting the marijuana grow industry’s high energy consumption:
– Its consumption of 1% of the nation’s electrical output represents a cost of $6 billion annually and produces the equivalent of 15 million tons of greenhouse gas emissions, which is equal to that produced by 3 million average cars in a year (The Carbon Footprint of Indoor Cannabis Production, Evan Mills);
– The U.S. marijuana grow industry’s energy consumption is six times that of the U.S. pharmaceutical industry and eight times more than the amount of energy required per square foot in the average U.S. commercial building (Columbia Environmental Law Journal, “Regulating Pot to save the Polar Bear: Energy and Climate Impacts of the Marijuana Industry,” Gina S. Warren, 2015).
– In Denver, the monthly electric bill for Colorado Harvest Company’s 10,000-square-foot grow facility was reported by the company to be $12,000. Other facilities in Colorado have reported bills almost double that amount (Colorado Public Radio, “How Much Electricity Does It Take To Grow Marijuana?” Grace Hood, 2015).
For cannabis cultivation facilities, lighting accounts for the greatest consumption of energy — typically about 40% of its total electricity usage. Not only does it represent the highest energy usage in an indoor growing facility, but it’s also the biggest contributor to the facility’s cooling requirements.
Currently, a variety of lighting manufacturers are developing energy-efficient lighting solutions for the cannabis industry, including ceramic metal halide, double-ended high-pressure sodium, LED and plasma fixtures.
Also being studied are fiber-optic energy systems capable of streaming and channeling sunlight into grow facilities.
Call to Action
To encourage the industry’s proactive pursuit of energy-saving methods, both the utilities and municipalities have responded with their own forms of motivation. Municipalities are offering both incentives and penalties to promote energy conservation. In 2015, Boulder County, Colorado, started requiring marijuana grow facilities to use renewable energy sources for half of their production in 2015 and all of their output starting in 2016. The county is levying a surcharge of 2.16 cents per kwh and applying the fees to the Energy Impact Offset Fund for programs focusing on more efficient ways to grow marijuana.
In Oregon, the Energy Trust of Oregon is providing cash incentives to marijuana grow facilities that are actively reducing their energy consumption, while many utility districts in Washington state have done the same. Other municipalities encourage the development of new building codes and/or LEED or Energy Star standards to be applied in the design of new grow facilities or retrofitting of existing facilities.
The utilities are encouraging grow facilities to modify their operations, where possible, by rescheduling their power draws to avoid peak demand periods. Utilities are also asking grow facilities to consider upgrading to more energy-efficient lighting, as well as offering incentives for energy-efficient upgrades. Seattle City Light established an incentive program for this purpose, and it’s also rewarding growers for the use of other energy-saving devices. One example is variable-frequency drives that manage a facility’s total HVAC energy consumption by slowing the supply-air fan and/or compressor to decrease energy consumption when cooling demand is lower than the HVAC equipment’s capacity. Other technologies being recommended for their energy-saving role are economizers, which are integrated with remote terminal units (microprocessor-controlled electronic devices) to draw in cool outside air to reduce cooling energy requirements.
To help grow facilities reduce their energy consumption, some utilities, such as Xcel, consult with grow facilities regarding these various technologies and lighting and their related levels of energy usage. Xcel also offers significant rebates for the application of energy-saving products and technologies, such as wrap-around plate dehumidification technology with atmospheric water generation for irrigation (see sidebar).
Moving forward, it’s safe to expect increased regulations as demands for energy conservation and sustainable practices become amplified. Agencies like Oregon’s Task Force on Cannabis Environmental Best Practices are cropping up in states across the country, ushered in by legislators who are intent on gaining control of the cannabis cultivation industry’s high energy consumption.
In the meantime, responsible grow facilities are doing their part to learn more about measures they can take to contain their energy usage and, at the same time, gain valuable operational and competitive advantages by doing so.
Walter Stark is the president of MSP Technology and a widely-recognized thought leader in dehumidification solutions. He has more than 50 years of experience in the heating, ventilating and air conditioning industry. During his career, he has won numerous awards, including the ASHRAE Regional Award for An Energy Efficient Project and the New York Governor’s Award of Energy Excellence. He was also featured in Popular Science magazine’s “Best of What’s New.”