Producing a kg of cannabis in an indoor cultivation emits 4600 kg of carbon dioxide and producing a marijuana cigarette is like leaving a bulb on during 25 hours. These kinds of cultivations need so much water and energy to work that it could be harmful to the environment. However, there are many ways to minimize their carbon footprint.
On average, producing one kg of processed cannabis indoors leads to the emission of 4600 kg of CO2 to the atmosphere. This measure is what is known as carbon footprint, a variable that measures the total amount of greenhouse gas emissions produced by human activities. For example, producing 1 kilogram of cannabis is equivalent to crossing the USA from coast to coast seven times by car. If we're talking about a single joint, instead, we could say that it's like leaving a light bulb on for 25 hours or like elaborating 8.5 L of beer. There's also the issue of water because, despite being surprisingly resistant, cannabis may need to be provided with lots of it, depending on the structure and the pot size. More and more countries are removing all restrictions regarding the use of cannabis, both for recreational and therapeutic use. In the States, where many territories have actually removed those restrictions, almost 2 out of 3 citizens are in favor of decriminalizing it, according to a recent report made by the consulting company Gallup. The figures, about 65 % of the population, are the highest in the last 50 years. With less fear of possible reprisals, an ever-growing market and an increasingly-open society, the cannabis industry has to increase its production levels. It is also true that more and more cannabis users are starting to grow their own plants, either at home or in the open air. This trend is driven by the pursuit of security and the desire to have a better control over the process and the yields. Unfortunately, though, this growing tendency can also lead to severe environmental damage: in order to grow, plants need a lot of energy that costs not only the owners but also the planet a lot. According to an investigation, published in 2011, the cannabis industry consumed 1 % of the total amount of energy consumed in the entire USA, a figure that supported another research study made last year claiming cannabis cultivations to consume $6 billion every year in energy, which is the amount of energy needed to supply 1.7 million homes.