Marijuana advocates are fond of calling their favorite weed a natural product, the epitome of a green commodity. But commercial pot cultivation — increasingly done indoors with 1,000-watt lamps substituting for sunlight — has a Godzilla-sized carbon footprint, according to a UC Berkeley energy analyst's report.
California's indoor pot crop, estimated at more than 2,000 tons a year, consumes $3 billion worth of electricity, or as much as 1 million average homes. It also produces as many greenhouse gas emissions as 1 million cars, according to the report by analyst Evan Mills, titled "Energy Up in Smoke."
A single marijuana joint represents two pounds of carbon dioxide emissions, the same as running an ordinary 100-watt light bulb for 30 hours in California, the report said.
Humboldt County pot activists, a Sonoma County medicinal marijuana dispensary owner, an Oakland pot lab operator and a narcotics officer agree that indoor pot cultivation consumes an inordinate share of kilowatts.
"Medical cannabis is supposed to be the greenest of all green industries," said Robert Jacob, proprietor of the Peace In Medicine Healing Center dispensaries in Sebastopol and Santa Rosa. "Instead, it's one of the largest (environmental) impacts that we have."
In marijuana-rich Humboldt, Mendocino and Lake counties, average household power consumption ranges from 20 percent to 40 percent above the norm for the PG&E service area. Sonoma County households match the systemwide average, according to PG&E.
All along the North Coast, pot's power grab is gaining attention.
"We here think of it as our Frankenstein monster," said Charley Custer of Redway, in the heart of Humboldt County's pot belt.
He's part of a group called Grow it in the Sun, formed a year ago to discourage medical marijuana users from puffing indoor-grown pot.
"We live in an agricultural paradise," Custer said, recalling the birth of Humboldt's marijuana industry in the 1970s, originally all outdoors. Indoor growing "just seems literally insane to us," he said.
Custer estimates the Humboldt pot crop value at more than $1 billion, about equally divided between indoor and outdoor production.
Indoor weed typically costs more than outdoor varieties, and enjoys a reputation for higher potency that experts say is not necessarily deserved.
Mills' report, released earlier this month, says that indoor production of a kilogram (2.2 pounds) of marijuana in California results in 2,000 kilograms of carbon dioxide emissions, with high-intensity grow lamps accounting for one-third of the carbon footprint.
Air conditioners, dehumidifiers, ventilation fans, water pumps and heaters, space heaters and carbon dioxide generators add to the power drain.
The impact is heightened by the use of diesel generators to power indoor grow sites that are off the electrical grid and account for about half of Humboldt County's indoor production, as well as occasional fuel spills, Custer said.
<NO1><NO>Jacob and Custer contend that law enforcement, especially helicopter surveillance by the state's Campaign Against Marijuana Planting, or CAMP program, established in 1983, drove pot cultivation indoors.
Proposition 19, the marijuana legalization ballot measure rejected by state voters last year, had Oakland and other cities anticipating warehouse-scale indoor cultivation with taxes to enrich city coffers, Jacob said.
Jacob, who said he is a "big advocate of outdoor cultivation" himself, lists indoor or outdoor origin on the labels of all the medical pot his dispensaries sell.