Washington’s indoor pot grows could be big power suck

A new study says all the indoor marijuana growing operations springing up in Washington state could put a significant demand on the region’s power supplies. Planners are keeping a close eye on the situation.

The Northwest Power and Conservation Council is currently updating its 20-year forecast of regional electricity demand as part of the Northwest Power Plan – which it issues every five years.

Pot growing caught the attention of planners after seeing what happened in Colorado, where the explosion of growers and large-scale industrial operations fueled massive energy consumption, says Tom Eckman, director of the council’s Power Planning Division.

Eckman says it takes the same amount of electricity to grow just four pot plants indoors as it does to power 29 refrigerators.

“You’re installing 1,000 watt lights over about every two plants and running those 16 to 18 hours a day to grow the product over a 10, 12, 14 week cycle. It’s a pretty significant consumption of electricity.”

The council studied a number of growers across the state earlier this summer after they were granted licenses by the Washington State Liquor Control Board. It determined demand for electricity could grow between 60 and 160 average megawatts over the next few years.

“That’s significant,” Eckman says. “That’s about half of the size of a new combustion turbine gas generating plant.”

To put it in perspective, the council compared marijuana production to aluminum. And Eckman says the findings were surprising.

“It takes about 5,000 kilowatt hours to produce a kilogram of cannabis. When we were looking in history it took about 15 to 20 kilowatt hours to produce a kilogram of aluminum in this region.”

The demand could be far greater if other states in the region legalize marijuana as well.

While the planning process is used to determine demand and the best way to deliver more power, the council also studied ways the industry can reduce energy use by improving efficiencies.

Growers could lower electricity used by about 30 percent by increasing their use of LED lighting and high efficiency heating and ventilation systems, Eckman says.

He also says the council found energy-efficient LED systems increased the yield of two strains of pot by 6 percent, which could be a big incentive for growers.

It’s all just part of what will become an increasing focus for the council in coming years as more growers go into business. But in the end, he says while it brings some societal issues with it, the council isn’t treating marijuana any differently than a data center or other industry.

“It’s different than a lot of the other things we look at that increase electrical consumption. The Facebook data center is pretty visible in the neighborhood. And this particular agricultural growth product tends to be a little more invisible in the neighborhoods,” he says. “But still, it’s just another use.”