When you smoke a blunt, you are responsible for two pounds of carbon dioxide emissions. At least according to a study from Lawrence Berkeley National Laboratory. The same study, by energy analyst Evan Mills, reports that US pot growers are responsible for one percent of national electricity consumption. In California, the top pot-producing state, that percentage increases to 3% for all electricity use and 8% of household use.
Minimal information and producer consideration of energy use, coupled with adaptations for security and privacy, lead to particularly inefficient configurations and correspondingly large energy consumption and greenhouse-gas emissions. If improved practices applicable to commercial agricultural greenhouses are any indication, the energy use for indoor Cannabis production can be reduced dramatically. Cost-effective efficiency improvements of 75% are conceivable, which would yield energy savings of about $25,000/year for a generic 10-module growing room. Shifting cultivation outdoors eliminates most energy uses (aside from transport), although the practice can impose other environmental impacts."Energy up in Smoke: The Carbon Footprint of Indoor Cannabis Production" (via National Geographic)