Category: Cannabis

Five ways cannabis can contribute to a green future

24K-Production/Shutterstock

by Julyan Levy, Coventry University

Cannabis legalisation could raise £1.5 billion for the UK economy, according to a recent report from the charity Transform. But aside from this plant’s economic benefits, cannabis also has many ecological advantages.

My research into the potential role of cannabis in shaping a fairer and healthier world never fails to excite me. Cannabis flowers became legally allowed as a medicine in the UK in 2018, but its origins as a medicinal herb in Britain dates back to at least Anglo-Saxon times. Its popularity is evident in the many place names scattered across the country, from Hemel Hempstead in Hertfordshire to Littlehempston in Devon.

Hemp is a colloquial term for the cannabis plant, Cannabis sativa. Hemp often refers to strains of cannabis that have had its main psychoactive chemical, tetrahydrocannabinol (THC), bred out of the female flowers.

Due to the negative associations cannabis has picked up over the past 50 years of prohibition, hemp farmers have distanced themselves from using the term cannabis. In the UK, this association has resulted in strict conditions for growing hemp creating a barrier for farmers.

In recent years, cannabidiol (CBD), the main non psychoactive chemical found in female cannabis flowers, has become popular as a wellness product. CBD is abundant in low-THC hemp flowers, so it’s easy for the lines between hemp and cannabis to become blurred.

It’s all cannabis. This plant has some incredible environmental benefits, from improving soil health to storing carbon. Here are five ways that cannabis plants can contribute to a greener planet:

1. Productive harvests

Hemp stems have a woody core, known as shivs, that can be mixed with lime to make hempcrete, a carbon-neutral alternative to concrete. Concrete production is one of the major sources of global greenhouse gas emissions. Hempcrete could be used to build eco-friendly social housing across the UK.

Hemp seeds are a nutritious food source, high in protein and omega-3. With the UK’s food system in crisis, hemp seeds and the oil they produce could be a more widespread sustainable homegrown food source if hemp could be grown on an industrial scale.

But industrial monocultures of crops are harmful to biodiversity. One alternative is agroecology – working with nature to prioritise biodiversity through small-scale farming.

Hemp is ideally suited to agroecology, but it’s not an easy crop to grow in the UK because licensing laws make it very difficult for hemp farmers to tap into a global market worth billions.

Farmers at one community farm, Hempen in Oxfordshire, sowed their first hemp crop over an area of 30 acres. In 2019, Hempen were forced to destroy their CBD harvest as their licence wasn’t renewed.

In California, THC strains are allowed. One farming community started producing its own CBD-based medicines on just one acre of land. Others use the plant in other interesting ways, from rehabilitating formally incarcerated people to off-grid market gardens.

man farmer wearing hat kneels by tall green hemp crop
Hemp offers potential as a fast-growing crop that enriches soil health. MAR007/Shutterstock

2. Healthy soils

Hemp seedling. Julyan Levy

Soil is essential for growing 98.8% of our food. Yet, it is often contaminated with toxic chemicals from industrial processes or the legacies of war.

A process known as phytoremediation cleans the soil of these toxic contaminants. Hemp’s deep roots have a high tolerance for absorbing dangerous heavy metals. It is also a great break crop – this is a way for farmers to rotate the types of crops they grow to keep the soil healthy.

3. Plastic alternatives

Plastic is poisoning our bodies and our planet. Recent reports suggest that the human brain may contain enough microplastics to make a spoon.

Bioplastics made from hemp are biodegradable, composting down into organic matter leaving no microplastics. Hemp bioplastics are already being used by a number of commercial companies from building cars to packaging.

Bioplastics do not offer a complete solution, but with the right infrastructure they could help reduce the need to derive more plastics from fossil fuels.

4. Carbon storage

The stems and roots of hemp are fibrous and hardy. Julyan Levy

Trees and other plants remove carbon dioxide from the air through the process of photosynthesis. Hemp is great at this, storing twice as much carbon dioxide than trees.

Hemp is easy to grow without synthetic chemical inputs. It requires virtually no pesticides and reaches maturity much more quickly than trees. Once it absorbs the carbon, it’s easily stored in hempcrete blocks that can be used in construction.

5. Energy storage

It’s very difficult to store excess energy from renewable sources for use at a later date when the sun might not be shining or the wind isn’t blowing. Big batteries are one solution but these require mining precious metals.

Another solution are supercapacitors – mega-efficient energy storage solutions that can be as small as a coin. Graphene, a flat material stronger than steel, is an essential element in the production of supercapacitors but it’s expensive and energy-intensive to make.

The whole stem biomass (unused plant waste) from cannabis could provide a low-cost way to make graphene. Research shows that supercapacitors using hemp-based graphene perform much more efficiently than current commercial models.

Hemp has many other known uses, from textiles to paper. The UK could lead the way in hemp innovation. The previous UK government did announce some minor changes to hemp licensing. Now, further changes to legislation could help farmers to harness the potential of this wondercrop in the fight against climate change.

Julyan Levy, PhD Candidate, Social Sciences, Coventry University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Growing weed takes more energy than mining bitcoin. Can it go green?

Read the full story in the Washington Post (gift article).

Growing weed inside uses about 1 percent of U.S. energy and pollutes more than cryptocurrency mining. There’s a better way to fuel America’s high.

New pesticide exposure test developed to protect inexperienced cannabis farmers

Read the full story from the University of Toledo.

Chemists created a more reliable, robust and efficient way to monitor pesticide exposure and help protect the health and safety of agricultural workers, especially for emerging sectors like the cannabis industry.

A Legal pot problem that’s now plaguing the streets of America: Plastic litter

Read the full story at Inside Climate News.

Waste packaging from a burgeoning and newly legalized marijuana industry litters streets across the country, adding to a global crisis of plastic waste.

In New York, regulators who are making the state’s first-ever rules for the retail sale of recreational marijuana hope they have answers to limit their state’s contribution to the problem. They’ve been working to include sustainable packaging requirements into the licenses that businesses will need to open by the end of this year.

However, at least one prominent environmental advocate fears New York—and other states grappling with a new and booming industry—aren’t requiring enough producer responsibility for the environmental impacts of their products.

A primer on composting cannabis residuals

Read the full story at Biocycle. [Part 1][Part 2]

The rapid legalization of cannabis in the U.S. has created a new urgency to compost cannabis residuals versus disposing of them in landfills and incinerators.

Illegal marijuana farms take West’s water in ‘blatant theft’

Read the full story from the Associated Press.

From dusty towns to forests in the U.S. West, illegal marijuana growers are taking water in uncontrolled amounts when there often isn’t enough to go around for even licensed users. Conflicts about water have long existed, but illegal marijuana farms — which proliferate despite legalization in many Western states — are adding strain during a severe drought.

An inconvenient truth (about weed)

Read the full story from Politico.

Federal laws bar cannabis from crossing state lines, driving up the cost — and the emissions — of an industry using indoor grow operations.

Episode 25: The ebb and flow of cannabis waste

Via Waste360.

The U.S. cannabis industry is expected to add $92 billion to the country’s economy in 2021, according to MJBizDaily. As the industry continues its upward momentum, producers of cannabis products that range from mints to gummies to dissolvable powders are seeking ways to reduce plastic packaging while remaining compliant. In this episode of Stef Talks Trash, Brooks Allman, founder of cannabis brand ebb, discusses the state of waste management in the cannabis industry and the challenges that come with sustainably-minded packaging.

As a crop, cannabis has enormous carbon emissions

Read the full story at Ars Technica.

Back in the pre-legalization days, cannabis production meant finding a rarely visited patch of land and growing outside, or it meant taking cultivation indoors—typically to a basement where your product wouldn’t be visible from the outside world. But the power-use involved in lighting a basement growing space was legendary.

With legalization, it’s really only the scale that has changed. Most legal marijuana is grown indoors, with some pretty hefty electrical use to match. Now, researchers have attempted to quantify the greenhouse gases emitted, and they came up with some impressive figures. Based on their calculations, cannabis production results in over 2,000 kilograms of carbon dioxide emitted for every kilogram of product (defined as dried flowers), and its legalization has had a measurable effect on Colorado’s greenhouse gas output.

Growing cannabis indoors produces a lot of greenhouse gases – just how much depends on where it’s grown

Growing cannabis indoors is an energy-intensive process. Plantlady223 via Wikimedia Commons, CC BY-SA

The Research Brief is a short take about interesting academic work.

by Jason Quinn and Hailey Summers (Colorado State University)

The big idea

Indoor cannabis production is a major source of greenhouse gas emissions, and the environmental effects vary significantly depending on where it is being grown, according to our new study.

The lights used to grow weed indoors use a lot of electricity, but facilities require a lot of energy to maintain a comfortable environment for the plants. That means air conditioners or heaters to maintain proper temperatures. Producers also pump carbon dioxide inside to increase plant growth. This accounts for 11% to 25% of facilities’ greenhouse gas emissions.

But the biggest energy use comes from the need to constantly bring fresh air into growing facilities. All of this outside air needs to be treated so that it is the correct temperature and humidity. This is a very energy-intensive process since the air exchange rate is typically so high.

All of these inputs contribute to greenhouse gas emissions, a lot more in some regions than others.

Using Department of Energy, Environmental Protection Agency and industry data, we found that growing pot indoors leads to higher greenhouse gas emissions in the Mountain West, Midwest, Alaska and Hawaii than compared to the Pacific and Atlantic coasts. This is because climates are milder on the coasts, so you need less heating or air conditioning and because the electric grids use more clean energy

Cannabis grown in Southern California has the lowest emissions, at 143 pounds of carbon dioxide equivalent per ounce of dried cannabis. Meanwhile, eastern O’ahu in Hawaii has the highest emissions, at 324 pounds of carbon dioxide equivalent per ounce. That’s roughly equivalent to burning 16 gallons of gasoline.

A map showing the midwest and rocky mountains in dark red while the coasts are pale red or white.
Places with more extreme temperatures and fewer renewable energy sources had the highest greenhouse gas emissions. Jason Quinn, CC BY-ND

Why it matters

Policymakers and consumers aren’t paying much attention to environmental impacts of the cannabis industry. In Colorado, the weed industry accounts for 1.3% of the state’s total annual emissions. This is similar to emissions from coal mining and trash collection for the entire state.

Currently, there is little to no regulation on emissions for growing cannabis indoors. Consumers aren’t thinking about the environmental effect either. As a whole, this industry is developing and expanding very quickly without consideration for the environment.

What still isn’t known

The cannabis industry is so new that researchers don’t even know how much is grown indoors. Additionally, every indoor operation is unique. Some are old warehouses using outdated equipment, while others are much more energy-efficient.

Growing cannabis outdoors or in greenhouses could be one way to remove the need for lights and environmental controls. However, researchers don’t know the greenhouse gas emissions associated with these growth methods either. All these unknowns make it hard to develop polices or best management practices.

What’s next

Our team’s goal is to better quantify and communicate the environmental impact of cannabis production so that those who want to reduce greenhouse gas emissions will be better informed.

We aim to show greenhouse gas emissions per serving of tetrahydrocannabinol, the chemical that produces the “high.” Our preliminary results show that one serving of THC – roughly 10 mg of dried flower – is likely to have higher greenhouse gas emissions than a serving of beer, wine, spirits, coffee or cigarettes, regardless of the location the weed was grown.

Our team is also interested in understanding where weed could be grown if federal legalization happens. Legalization might allow policymakers and producers to grow weed in places and in ways that are much more environmentally friendly, but they need the knowledge to do so.

Jason Quinn, Associate Professor in Mechanical Engineering and Director of the Sustainability Research Laboratory, Colorado State University and Hailey Summers, Ph.D. Student in Mechanical Engineering and Sustainability, Colorado State University

This article is republished from The Conversation under a Creative Commons license. Read the original article.