Ecological Footprints of Hemp and Cotton: A Decisive Comparison

If the Gods of the Universe are maintaining a ledger, humans are their Non Performing Assets. 

That’s because we’re groaning under massive planetary debt. 

We have 1 Earth. But, we are using the resources of 1.75 Earths. And if we all started living like the average USA resident (which seems to be where we’re headed), we’d need more than 5 Earths!

Ecological Footprints of Hemp and Cotton: A Decisive Comparison

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One thing is clear, we need to cut down on how much land we are using. 

How? Be mindful of what we consume. An easy way of practicing this mindfulness is by switching your cotton products to hemp.

Research shows that the ecological footprint of hemp is half that of cotton.

Cotton represents the higher end of the ecological footprint – 2.17 gha for organic cotton in the USA to 3.57 gha for conventional cotton in Punjab. 

The ecological footprint of hemp is lower – 1.46 gha and reaching 2.01 gha. 

The global hectare (gha) measures our demands on the Earth (ecological footprint) and the ability of the Earth to supply our demands (biocapacity). So, as per the results, hemp requires almost half the land to produce the same amount as cotton. 

To become a conscious consumer, you need to understand what actually causes these variations among products. And we are going to help you with that. 

Why did we write this blog?

Because we believe you need the right info, to make the right decisions. 

And this blog will give you plain-English answers to complex questions.

We know that you’d want to understand stuff like:

  • What causes these variations
  • How you can shop for eco-friendly garments
  • How you can detect half-truths in the claims of fashion labels

How to benefit from this blog?

To make that information accessible to you, we have broken down complicated research data into simpler bits.

This article will cover:

  • The factors that affect the ecological footprint of the crops 
  • Difference between organic and non-organic crops 
  • Energy requirements
  • CO2 emissions 
  • ecological footprint

Factors that determine the ecological footprint of the above-mentioned crops:

  • Type of crop
  • The local soil conditions
  • The local climate conditions 
  • Choice of cultivation
  • Choice of processing methods

Difference between cotton and organic cotton

Organic cotton does not use toxic, persistent agro-chemicals, and GM organisms.

Instead of using conventional methods, crop rotation is practiced to maintain soil fertility. Leguminous plants, cover cropping, animal manure, and compost additions, and naturally occurring rock powders are used.

Pesticides are subsidised by weed and a natural balance is restored between pest and natural enemy populations. 

Difference between hemp and organic hemp

There is very little difference between cultivation of hemp and organic hemp. This is because hemp grows faster than weed and is usually not plagued by pests.

What research tells us

This study by BioRegional Development Group and World Wide Fund for Nature calculated ecological footprints of  five textiles: cotton, organic cotton, hemp, organic hemp and polyester. 

The paper is titled ‘Ecological Footprint and Water Analysis of Cotton, Hemp and Polyester’ and it found that hemp has the lowest ecological footprint.  

Ecological Footprints of Hemp and Cotton: A Decisive Comparison

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But how did the researchers determine that? 

Keep reading to find out detailed information of how ecological footprint was calculated for cotton and hemp, and the variations between the two. 

Research parameters:

  • Data was collected from different regions.
  • The results vary depending on cultivation practices. 
  • All the hemp case studies were based in the UK.
  • Traditional and experimentation methods of cultivating hemp were also compared. 
  • In the experimental methods processing was done using Fibrenova technology green decortication and a non-aligned system with chemical de-gumming.
  • In the traditional method hemp was cultivated by Hemcore, dew retted and processed through a non-aligned system with experimental chemical de-gumming. 
  • The study took account of not only crop growth water requirements but also water use in cultivation, pesticide and fertiliser application and harvesting.
  • The data used for water calculations was from secondary resources. 

Energy requirements: hemp vs cotton

Ecological Footprints of Hemp and Cotton: A Decisive Comparison

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Energy requirements of Cotton

  • The range of energy required for cotton varies from 11,711MJ to 25,591MJ.
  • 11,711MJ energy went into cultivating organic cotton in a low energy use system in Punjab.
  • In a high energy use system in the USA, the figure rose to 25,591MJ for regular cotton.This is because regular cotton requires greater energy inputs into the crop cultivation stage.
  • If synthetic fertilisers, herbicides, and energy intensive irrigation schemes were omitted a total of 12,929MJ of energy consumption could be reduced. 

Energy requirements of Hemp

  • The energy range for hemp is from 15,009MJ to 32,622MJ.
  • Traditionally processed organic hemp requires 15,009MJ of energy. 
  • Conventionally grown hemp processed through a green decortication system requires 32,622MJ of energy. This means, energy savings of 6,596MJ are still achieved when hemp is cultivated organically instead of conventionally.
  • In contrast to cotton, the greatest energy requirements for hemp are in the fibre production stage, as the cultivation of the crop requires fewer inputs. 
  • The hemp fibre production process that requires the least energy at 13,500MJ is the traditional system of scutching, hackling, roving, drawing and wet spinning.

The paper also studied the experimental green decorticated non-aligned fibre production process. This process involves scouring, drying, carding and dry spinning. 

The study found that this process is much more energy intensive requiring 21,449MJ per tonne of spun fibre. A large proportion of this energy (13,863MJ) is required to heat water to temperatures up to 110°C.

Carbon Dioxide emissions: hemp vs cotton

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The CO2 emissions associated with the production of one tonne of spun fibre are closely linked to the energy requirements of producing that fibre. 

This means that CO2 emissions and energy requirements are heavily influenced by each other. 

Carbon Dioxide emissions by Cotton

  • CO2 emissions associated with cotton range widely from 2.35 to 5.89 kg of CO2 per tonne of fibre.
  • Organic cotton in the USA produced 2.3kg of CO2 emissions and regular cotton produced 5.89kg. 
  • Organic cotton in the Punjab produced 2.3kg of CO2 emissions and regular cotton produced 5kg. 

As seen in the ‘energy requirement section’, the model followed by Punjab was a low energy one. However, when the study calculated energy requirements,  organic cotton grown in the USA has the lowest value. 

This could be because of the different fuel use in both the countries. This implies that type of fuel used to generate energy in India produces greater CO2 emissions per unit of fuel than that used in the USA, which in turn produces greater CO2 emissions.

Carbon Dioxide emissions by Hemp

  • The range of CO2 emissions from 4kg to 6kg. 
  • Traditional organic hemp produced almost 4kg of CO2 emissions and the experimental method of production produced almost 5kg of CO2 emissions. 
  • Traditional hemp produced almost 5kg of CO2 emissions and the experimental method of production produced almost 6kg of CO2 emissions. 

Ecological footprint: hemp vs cotton

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The ecological footprint is represented in global hectares (gha), of producing one tonne of spun fibre.

Ecological footprint of Cotton

  • The ecological footprint of cotton represents the higher end. The results ranged from 2.17 gha for organic cotton in the USA to 3.57 gha for conventional cotton in Punjab.
  • Crop cultivation represented the greatest proportion of the ecological footprint in the cotton case study. 

This means that the cotton system, particularly in Punjab, is the least productive, especially when the inputs are reduced at the cultivation stage to grow organic cotton. To put it simply, Punjab required a greater land area to yield the same amount of cotton as the USA.  

Ecological footprint of Hemp

  • Hemp represents the lowest ecological footprint. 
  • Footprint of hemp does not vary significantly in the different case studies. It starts at 1.46 gha and reaches 2.01gha.
  • Hemp productivity levels are much greater with yields of up to 3 tonnes of dry fibre per hectare compared to 1.35 tonnes of cotton lint per hectare.

Other insights from the results

Let’s put this data into perspective to better understand what these figures mean when it comes to the individual textiles. 

  • Crop cultivation is responsible for a huge proportion of the ecological footprint. ‘Organic Cotton–USA’ – 84% and ‘Cotton–Punjab’ – 90%.
  • Land area is the major contributor to the ecological footprint. 75% in USA and 69% in Punjab.
  • For organic cotton, the spinning process plays the next greatest role at 12% of the total ecological footprint. In cotton, fertilisers and pest control make up 11% of the total.
  • Harvesting and picking represents 22% of the ‘Traditional Organic Hemp–UK’ total. The drying process makes up 27% of the ‘Green Decortication Hemp’ total.

It’s no secret that hemp is much better than other textiles on the market. However, it is often pitted against organic cotton. While organic cotton has its charms, hemp is by far the superior textile. It requires less energy, and water, releases less carbon dioxide and the ecological footprint of hemp is lower.

If you want to lower your ecological footprint, hemp is the way to go. With increasing knowledge about the benefits of hemp, you can begin substituting your everyday products with hemp-based items. The easiest place to start is with hemp fabric. The clothes are soft, last longer, and are better for you and the environment.

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