Hemp - Carbon Sequestration

Hemp Carbon Sequestration, Pollution Solution



Sources: Hemp Tank (HT) Hemp Foods Australia (HFA) The Hemp Plastic Co (HPC) British Hemp Assoc (BHA) Green Flower (GF) Sunstrand (SS)



One hectare of industrial hemp can absorb approximately 15 tonnes of CO2 (Lhoist 2016) making it one of the fastest CO2-to-biomass conversion tools. Industrial hemp is the perfect carbon sink because it absorbs more CO2 per hectare, annually, than any other commercial crop or commercial forestry. (BHA  https://www.britishhempassociation.co.uk/ )


Hemp begins sequestering carbon the moment it is seeded; conservatively, hemp cultivation yields a sequestration ratio of about 1.5 units of sequestration per unit produced. In Layman’s terms, one ton of harvested hemp fiber should sequester 1.62 tons of CO2.

Hemp can also sequester carbon back into the soil through a process called, biosequestration. In this process, hemp captures carbon emissions from the atmosphere. When the crop is harvested, the hemp can be slow-smoldered, not burned, to create biochar. This charcoal-esque product can then be mixed with other nutrients and returned into the soil. According to a paper provided by Holon Ecosystem Consultants, hemp might give as much as 13 tons of charcoal per hectare annually, which would triple the output of Salix (a popular biomass crop) plantations.

The first hemp application that usually comes to mind is in building and construction. According to the United Nations Environment Programme, the building sector contributes up to 30% of global annual greenhouse gas emissions and uses up to 40% of all energy. In recent years, Europe has been leading the way back into energy-efficient, hemp-based buildings, with Canada and the US following suit. The most popular in this recent surge: hempcrete. Hempcrete is a fiber-reinforced material made from a combination of hemp hurd, lime, and water. This combination creates a bio-composite material that is lighter and more flexible than concrete while keeping the structural strength and thermal properties ideal for use in non-load bearing construction projects and insulation. But what about its carbon footprint? A life cycle analysis on a 120 square foot Hempcrete wall would find an emission of 3880 pounds of CO2, but this would not include the materials’ potential carbon sequestration. As we previously mentioned, one ton of hemp fiber should sequester 1.62 tons of CO2 over the growing process, but hemp doesn’t stop sequestering there. Over time, materials in hempcrete undergo calcination, absorbing more CO2. Calcination is the process where materials heat up, below its boiling point, to drive off volatile matter or to effect changes. During this process, and under the same circumstances previously mentioned, the 120 square foot hempcrete wall should sequester 2400 pounds of CO2, leaving only 1480 pounds of CO2 created by the process. Those 1480 pounds are easily offset by the carbon sequestered in hemp production, leaving the entire project carbon negative. Natural materials are used in hundreds of composite applications. One of the most popular composite applications is thermoplastics. These are a type of plastic made from polymer resins, like polyethylene, polypropylene, polystyrene, polycarbonate, and acrylic. These resins and natural materials can create anything from surfboards to eyeglass lenses. With this much potential, imagine the good that could be done by replacing a little plastic with natural fibers. A study in 2003 by the University of Toronto found that we could save 50 000 MJ, or 3 tons of CO2, per ton of thermoplastic by replacing 30% glass fiber reinforcement with 65% hemp fiber. We can also address the carbon storage capabilities in these natural fiber composites. The same writers of the University of Toronto’s study estimated a carbon storage potential of 715 pounds per metric ton of hemp-based polypropylene composite. This means that the carbon is not sent back into the atmosphere but trapped in the material for years and years. (SS  https://www.sunstrands.com/2019/hemp-the-solution-for-global-warming/ )


study by the Commonwealth Scientific and Industrial Research Organization and Imperial College of London found that 60% of seabirds today have plastic in their gut. By 2050, they expect that number could rise to 99%

How does this plastic end up in wildlife? 

When plastic is exposed to sunlight, it breaks down into smaller pieces. These small pieces of plastic end up being ingested by marine and other sea life. As plastic disintegrates, it moves down the food chain.

Animals, like humans, are not designed to consume plastic.

Ingesting plastic can lead to a number of detrimental health effects. Many of which we are likely still unaware of.

Hemp plastic, on the other hand, is biodegradable. It is also non-toxic. Instead of filling up our seas with deadly petrochemical plastics, we could create sustainable initiatives to recycle hemp plastic safely. (GF https://www.green-flower.com/articles/448/7-ways-hemp-plastic-could-change-the-world)


There is more carbon dioxide in the atmosphere today than at any point in history during the last 80,000 years.

Rising carbon dioxide concentrations are responsible for the warming of the earth’s atmosphere. Otherwise known as the greenhouse effect. Much of this rise in carbon dioxide can be attributed to the burning of fossil fuels.

Conventional plastics are made from fossil fuels like petroleum. Therefore, plastic is a big contributor to rising CO2 emissions.

Hemp plastic and products can actually reduce the greenhouse effect. This is because hemp absorbs carbon dioxide from the atmosphere and converts it into oxygen. In addition, hemp plastic generates zero toxic byproducts.

Seed to sale, hemp plastic is a sustainable process. This is the complete opposite from the toxic manufacturing process of petrochemical plastics. 


Even once hemp is manufactured into plastic, it continues to be sustainable. Hemp plastic is 100% biodegradable. Which means that under the right conditions it will decompose within a few months. (Unlike traditional plastics that take an indefinite amount of time while leeching toxins in the process.)

Conventional plastics are not worth the risk. The alternative is right in front of us.

No other natural resource offers the capabilities of hemp. Start to finish hemp is renewable. While hemp certainly isn’t the only answer to our environmental and health concerns, it’s a start.(GF)





Plastic Pollution

  • As of 2018, 335 million tons of plastics are produced globally each year.

  • 45% of all plastics are produced in the United States.

  • 29% of plastics produced in the US are used for packaging (15% building, 14% consumer).

  • The packaging market, in the United States alone is worth $100 billion, a quarter of the global market.

  • In the United States over 60 billion pounds of plastic are discarded into the waste stream each year (from 4 billion in 1970). Most of this is in Municipal Solid Waste.

  • One-half of all discarded plastic comes from packaging. Almost one-third comes from packaging that is discarded soon after use.

  • Beach litter is 40-60 percent plastic, much of which often floats in from the sea. Such beach litter is hazardous to birds, fish and animals who die from ingesting it or becoming entangled in it.

  • Wide-scale postconsumer recycling of plastics is relatively new. Modern plastics are becoming harder to recycle. (HPC  https://hempplastic.com/facts/ )



Scientific climate data shows that we have entered the sixth mass extinction (we have lost 60% of our wildlife since 1970). We have very little time in which to create a carbon zero economy. Hemp can be the catalyst to creating a Green Industrial Revolution in a short space of time.

Imagine a future with a green industry which is ethical, responsible, non corporate and led by the people of Great Britain.  .  (HT  https://www.hemptank.co.uk/news/upcoming-projects/)


Hemp grows readily in most temperate or subtropical climates and is even capable of growing in climates ranging from Nepalese mountains to the equator. This allows for local production resulting in shorter transportation, less carbon thereby emitted, and thus more sustainable supply chains.  (HT)

Cotton covers 2.5% of the world's cultivated land yet uses 16% of the world's pesticides- more than any other single major crop. Runoff from this chemical cocktail can destroy sensitive ecosystems, even if chemicals are “properly applied” The most prevalent socio-economic impacts documented with agrichemical use have been fatalities, build up of pesticides in human and animal food chains, contamination of drinking water and ground water, build up of immunity by pests, and soil mycorrhizal disruption  (HT)


Irrigation: WWF studies have shown that it takes more than 20,000 liters of water to produce 1 kg of cotton, the equivalent of a single T-shirt and pair of jeans. For hemp the amount of water required is just 300-500 litres. It is estimated that approximately 73% of global cotton is harvested from irrigated areas. Worldwide, irrigation efficiency is lower than 40 per cent. The second order problems beyond stress on the water supply from irrigation of cotton include negative impacts on the regional freshwater quality including eutrophication, salinisation, pollution, wildlife contamination, raising water tables and habitat destruction.  (HT)


Traditionally hemp was processed by hand. After retting in the fields, simple wooden tools were used to separate the fibres, which were combed and carded by hand. All major processing stages along the cotton value chain, such as dyeing, bleaching and finishing, use large amounts of chemicals of various toxicity. Most of these chemicals, such as heavy metals, formaldehyde, azo dyes, benzidine and chlorine bleach cause environmental pollution of the mills’ waste water and many can be found as residues in the finished product. Some of them affect consumers’ health and are suspected of causing allergies, eczema or cancer. Furthermore socio- economic factors, associated with sweatshop worker impacts, can be huge. Recent studies clearly demonstrate the considerably larger energy requirement for production of synthetic fibre in comparison to hemp and cotton. Hemp represents the lowest ecological footprint of the three textiles. (HT)


All major processing stages along the cotton value chain, such as dyeing, bleaching and finishing, use large amounts of chemicals of various toxicity. Most of these chemicals, such as heavy metals, formaldehyde, azo dyes, benzidine and chlorine bleach cause environmental pollution of the mills’ waste water and many can be found as residues in the finished product. Some of them affect consumers’ health and are suspected of causing allergies, eczema or cancer (HT)