We'll admit it. The funnest part about reporting this week's revelation that the nation's indoor marijuana crop has the same annual carbon footprint as 3 million cars was being able to those rib self-righteous, eco-conscious medicinal users who think just because it's green, well, it's green.

But we talked to the man behind the international-headline-making research today, and he doesn't want to turn this into a prosecution of the hippie cannabis club.

No, in fact, says Lawrence Berkeley National Laboratory researcher Evan Mills, his work points, perhaps, to the need for further decriminalization efforts. Say what?

Yeah, maybe he's right. Here's his rationale:

If cultivating hydroponic weed is bad for the environment (and it is — indoor production is the equivalent of half of America's household computer use, Mills says), then maybe we should encourage eco-friendly grow methods.

Gas guzzlers?

Gas guzzlers?

But, Mills points out, that would be hard to do since one of the primary reasons for indoor growing is that it is out of site of law enforcement. “Criminalization certainly contributes to the problem in forcing it indoors,” he says.

In fact, cultivating large amounts of cannabis is a legal gray area in California, where you're really only allowed to grow enough for the other seriously ill people in your collective.

Yeah, right.

Some cities such as Berkeley have recognized the folly of trying to follow the letter of the law and now allow grow operations that are “carbon neutral,” thus encouraging them to find more fuel- and electricity-efficient grow appliances (lights, fans, heaters).

One of the great inefficiencies of the grow house, Mills says, is that some operators have turned to using diesel and gas portable generators so they'll stay off the grid and away from the cross-hairs of the law.

(A tried-and-true method of tracking grow houses is simply to check for unusually high electricity bills compared to those of neighbors').

A garden of green.

A garden of green.

But those generators make things worse, environmentally: Diesel generators use 70 gallons per plant, Mills says; gas is 140 gallons per plant. Not to mention emissions. That's four times the carbon footprint as would be used if growers just plugged into the grid, Mills says.

Smoking a hydroponic “joint is like having a 100 watt light on for 30 hours,” he says.

It would be better, he says, to stay on the grid and get an agricultural-use rate from the utilities with incentives to be environmentally efficient (just like other businesses).

What's more, if the industries producing those grow appliances had incentive to churn out more eco-friendly devices (a la EnergyStar), things would improve quickly. But getting government-backed rebates for electricity efficient grow lights seems a way off.

“That's a take away,” Mills says. “Whatever you think about criminalization, the reality is that it has contributed to this prodigious energy use and made it harder.”

There's always outdoor growing — if the law would back off of that. Although mass outdoor operations have their own environmental issues, including toxic runoff from pesticides and fuel-run generators.

Back to the small, backyard operation?

Sounds like a slow-food-like movement for marijuana. Mills even suggests that growers and dispensaries could capitalize on eco-consciousness and market their wares as more eco-friendly — green green:

“It's a call to action for this industry and maybe a business opportunity, too.”

LA Weekly