Why does wool get such high embodied energy ratings?

4 08 2009

The more I learn about organic farming the more impressed I become with the dynamics of it all.   As Fritz Capra has said, we live in an interconnected and self-organizing universe of changing patterns and flowing energy. Everything has an intrinsic pattern which in turn is part of a greater pattern – and all of it is in flux.  That sure makes it hard to do an LCA, and it makes for very wobbly footing if somebody takes a stand and defends it against all comers.

For example, I have been under the impression (based on some published LCA’s) that the production of wool is very resource inefficient, largely based on the enormous need for water: it’s generally assumed that 170,000 litres of water is needed to produce 1 KG of wool    (versus anywhere from 2000 to 5300 to produce the same amount of cotton).  That’s because the livestock graze on land and depend on rainwater for their water – and some LCA’s base the water use on the lifetime of the sheep (reminding me to check the research parameters when referring to published LCA’s).

In addition, industrial agricultural livestock production often results in overgrazing.  As we now see in the western United States, overgrazing in extreme cases causes the land to transform from its natural state of fertility to that of a desert. At the very least, it severely limits plant reproduction, which in turn limits the soil’s ability to absorb water and maintain its original nutrient balance, making overgrazing difficult to recover from. And then there’s methane: livestock are often vilified for producing more greenhouse gases than automobiles.

The exciting thing is that what is known as “holistic management” of the soil makes it possible to use animals to improve, rather than degrade, land.  What’s consistently ignored in the research  is the failure to distinguish between animals raised in confined feedlots and animals grazing on rangeland  in a holistic system.  Research on holistic land management is, in fact, showing that large grazing animals are a vital and necessary part of the solution to climate change and carbon sequestration. Read about holistic land management on the Holistic Managmeent Institute (HMI) website.

The reason holistic practices work, according to HMI, is that grazing animals and grassland co-evolved.  According to the HMI website, hooves and manure accomplish what mechanical tilling and petrochemical fertilizers cannot: healthy, diverse grassland with abundant root systems and improved soil structures that makes highly effective use of existing rainfall.  Domestic animals can be managed in ways that mimic nature, called “planned grazing”:  rather than allowing animals to linger and eat from the same land repeatedly,  animals are concentrated and moved according to a plan which allows the land long periods of rest and recovery.   This planned grazing allows the animals to till packed soil with their hooves, distribute fertilizer and seed in their manure and urine, and move from one area to another before they can overgraze any one spot. In fact, the animals help maintain the soil, rather than destroying it, and increase the amount of organic matter in the soil, making it function as a highly effective carbon bank. Properly managed, grazing animals can help us control global climate change:  soil carbon increased 1% within a 12 month period  in a planned grazing project (a significant increase).

This carbon is essential to not only feeding soil life and pasture productivity, but it also affects water infiltration rates. On one trial site where planned grazing was implemented, within two years, the  soil water infiltration rate increased eightfold in comparison to the conventional grazing treatment.

In addition, holistic management of grazing animals eliminates the need for the standard practice of burning crop and forage residues.  That burning currently sends carbon directly into the atmosphere.  If we convert just 4 million acres of land that’s operating under the traditional, conventional agriculture model to holistically managed land – so the residue is not burned – the carbon is captured rather than released.   Look at the difference in erosion in the picture below: compare the severely eroded, conventionally managed riverbank on the left with the Holistically Managed bank on the right.  All the shrubbery and grass means abundant root systems and healthy soil infrastructure underground – both of these sequester CO2.

HOLISTIC mgmtWhat you see on the right is the result of managed animal impact.                     Source: Holistic Management International

According to Christine Jones, Founder, Australian Soil Carbon Accreditation, “The fabulous thing about sequestering carbon in grasslands is that you can keep on doing it forever – you can keep building soil on soil on soil… perennial grasses can outlive their owners; they’re longer-lived than a lot of trees, so the carbon sequestration is more permanent than it is in trees: the carbon’s not going to re-cycle back into the atmosphere if we maintain that soil management… and there’s no limit to how much soil you can build… for example, we would only have to improve the stored carbon percentage by one percent on the 415 million hectares (1,025,487,333 acres) of agricultural soil in Australia and we could sequester all of the planet’s legacy load of carbon. It’s quite a stunning figure.”

 

Data from a demonstration project in Washington State is confirming other worldwide research that grazing could be better for the land than growing certain crops in dryland farming regions – it reverses soil decline (erosion and desertification), restores soil health, and instead of losing carbon through tilling or systems requiring inputs (like wheat farming) planned grazing sequesters carbon; biomass to soak up carbon is increased, and the use of fossil fuel has been reduced by more than 90%.  Wildlife habitat has improved.  The Washington State project even sells carbon credits.

In April of this year, Catholic Relief Service, one of the country’s largest international humanitarian agencies, is launching a worldwide agricultural strategy that adopts a holistic, market oriented approach to help lift millions of people out of poverty.   Read more about this here.

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Elephants Among Us

29 06 2009

 

Although most of the current focus on lightening our carbon footprint revolves around transportation and heating issues, the modest little fabric all around you turns out to be from an industry with a gigantic carbon footprint. The textile industry, according to the U.S. Energy Information Administration, is the 5th largest contributor to CO2 emissions in the United States, after primary metals, nonmetallic mineral products, petroleum and chemicals.[1]

The textile industry is huge, and it is a huge producer of greenhouse gasses.  Today’s textile industry is one of the largest sources of greenhouse gasses (GHG’s) on Earth, due to its huge size.[2] In 2008,  annual global textile production was estimated at  60 billion kilograms (KG) of fabric.  The estimated energy and water needed to produce that amount of fabric boggles the mind:

  • 1,074 billion kWh of electricity  or 132 million metric tons of coal and
  • between 6 – 9 trillion liters of water[3]

Fabrics are the elephant in the room.  They’re all around us  but no one is thinking about them.  We simply overlook fabrics, maybe because they are almost always used as a component in a final product that seems rather innocuous:  sheets, blankets, sofas, curtains, and of course clothing.  Textiles, including clothing,  accounted for about one ton of the 19.8 tons of total CO2 emissions produced by each person in the U.S. in 2006. [4] By contrast, a person in Haiti produced a total of only 0.21 tons of total carbon emissions in 2006.[5]

Your textile choices do make a difference, so it’s vitally important to look beyond thread counts, color and abrasion results.

How do you evaluate the carbon footprint in any fabric?  Look at the “embodied energy’ in the fabric – that is, all of the energy used at each step of the process needed to create that fabric.  To estimate the embodied energy in any fabric it’s necessary to add the energy required in two separate fabric production steps:

(1)  Find out what the fabric is made from, because the type of fiber tells you a lot about the energy needed to make the fibers used in the yarn.  The carbon footprint of various fibers varies a lot, so start with the energy required to produce the fiber.

(2) Next, add the energy used to weave those yarns into fabric.  Once any material becomes a “yarn” or “filament”, the amount of energy and conversion process to weave that yarn into a textile is pretty consistent, whether the yarn is wool, cotton, nylon or polyester.[6]

Let’s look at #1 first: the energy needed to make the fibers and create the yarn. For ease of comparison we’ll divide the fiber types into “natural” (from plants, animals and less commonly, minerals) and “synthetic” (man made).

For natural fibers you must look at field preparation, planting and field operations (mechanized irrigation, weed control, pest control and fertilizers (manure vs. synthetic chemicals)), harvesting and yields.  Synthetic fertilizer use is a major component of the high cost of conventional agriculture:  making just one ton of nitrogen fertilizer emits nearly 7 tons of CO2 equivalent greenhouse gases.

For synthetics, a crucial fact is that the fibers are made from fossil fuels.   Very high amounts of energy are used in extracting the oil from the ground as well as in the production of the polymers.

A study done by the Stockholm Environment Institute on behalf of the BioRegional Development Group  concludes that the energy used (and therefore the CO2 emitted) to create 1 ton of spun fiber is much higher for synthetics than for hemp or cotton:

KG of CO2 emissions per ton of spun fiber:

crop cultivation

fiber production

TOTAL

polyester USA

0.00

9.52

9.52

cotton, conventional, USA

4.20

1.70

5.89

hemp, conventional

1.90

2.15

4.10

cotton, organic, India

2.00

1.80

3.75

cotton, organic, USA

0.90

1.45

2.35

The table above only gives results for polyester; other synthetics have more of an impact:  acrylic is 30% more energy intensive in its production than polyester [7] and nylon is even higher than that.

Not only is the quantity of GHG emissions of concern regarding synthetics, so too are the kinds of gasses produced during production of synthetic fibers.  Nylon, for example, creates emissions of N2O, which is 300 times more damaging than CO2 [8] and which, because of its long life (120 years) can reach the upper atmosphere and deplete the layer of stratospheric ozone, which is an important filter of UV radiation.  In fact, during the 1990s, N2O emissions from a single nylon plant in the UK were thought to have a global warming impact equivalent to more than 3% of the UK’s entire CO2 emissions.[9] A study done for the New Zealand Merino Wool Association shows how much less total energy is required for the production of natural fibers than synthetics:

Embodied Energy used in production of various fibers:

energy use in MJ per KG of fiber:
flax fibre (MAT)

10

cotton

55

wool

63

Viscose

100

Polypropylene

115

Polyester

125

acrylic

175

Nylon

250

SOURCE:  “LCA: New Zealand Merino Wool Total Energy Use”, Barber and Pellow,      http://www.tech.plym.ac.uk/sme/mats324/mats324A9%20NFETE.htm

Natural fibers, in addition to having a smaller carbon footprint in the production of the spun fiber, have many additional  benefits:

  1. being able to be degraded by micro-organisms and composted (improving soil structure); in this way the fixed CO2 in the fiber will be released and the cycle closed.   Synthetics do not decompose: in landfills they release heavy metals and other additives into soil and groundwater.  Recycling requires costly separation, while incineration produces pollutants – in the case of high density polyethylene, 3 tons of CO2 emissions are produced for ever 1 ton of material burnt.[10] Left in the environment, synthetic fibers contribute, for example, to the estimated 640,000 tons of abandoned fishing nets in the world’s oceans.
  2. sequestering carbon.  Sequestering carbon is the process through which CO2 from the atmosphere is absorbed by plants through photosynthesis and stored as carbon in biomass (leaves, stems, branches, roots, etc.) and soils.  Jute, for example, absorbs 2.4 tons of carbon per ton of dry fiber.[11]

Substituting organic fibers for conventionally grown fibers is not just a little better – but lots better in all respects:  uses less energy for production, emits fewer greenhouse gases and supports organic farming (which has myriad environmental, social and health benefits).  A study published by Innovations Agronomiques (2009) found that 43% less GHG are emitted per unit area under organic agriculture than under conventional agriculture.[12] A study done by Dr. David Pimentel of Cornell University found that organic farming systems used just 63% of the energy required by conventional farming systems, largely because of the massive amounts of energy requirements needed to synthesize nitrogen fertilizers. Further it was found in controlled long term trials that organic farming adds between 100-400kg of carbon per hectare to the soil each year, compared to non-organic farming.  When this stored carbon is included in the carbon footprint, it reduces the total GHG even further.[13] The key lies in the handling of organic matter (OM): because soil organic matter is primarily carbon, increases in soil OM levels will be directly correlated with carbon sequestration. While conventional farming typically depletes soil OM, organic farming builds it through the use of composted animal manures and cover crops.

Taking it one step further beyond the energy inputs we’re looking at, which help to mitigate climate change, organic farming helps to ensure other environmental and social goals:

  • eliminates the use of synthetic fertilizers, pesticides and genetically modified organisims (GMOs) which is  an improvement in human health and agrobiodiversity
  • conserves water (making the soil more friable so rainwater is absorbed better – lessening irrigation requirements and erosion)
  • ensures sustained biodiversity
  • and compared to forests, agricultural soils may be a more secure sink for atmospheric carbon, since they are not vulnerable to logging and wildfire.

Organic agriculture is an undervalued and underestimated climate change tool that could be one of the most powerful strategies in the fight against global warming, according to Paul Hepperly, Rodale Institute Research Manager. The Rodale Institute Farming Systems Trial (FST) soil carbon data (which covers 30 years)  provides convincing evidence that improved global terrestrial stewardship–specifically including regenerative organic agricultural practices–can be the most effective currently available strategy for mitigating CO2 emissions.

At the fiber level it is clear that synthetics have a much bigger footprint than does any natural fiber, including wool or conventionally produced cotton.   So in terms of the carbon footprint at the fiber level, any natural fiber beats any synthetic – at this point in time.   Best of all is an organic natural fiber.

 

And next let’s look at #2, the energy needed to weave those yarns into fabric.

There is no dramatic difference in the amount of energy needed to weave fibers into fabric depending on fiber type..[14] The processing is generally the same whether the fiber is nylon, cotton, hemp, wool or polyester:   thermal energy required per meter of cloth is 4,500-5,500 Kcal and electrical energy required per meter of cloth is 0.45-0.55 kwh. [15] This translates into huge quantities of fossil fuels  –  both to create energy directly needed to power the mills, produce heat and steam, and power air conditioners, as well as indirectly to create the many chemicals used in production.  In addition, the textile industry has one of the lowest efficiencies in energy utilization because it is largely antiquated.

 

But there is an additional dimension to consider during processing:  environmental pollution.  Conventional textile processing is highly polluting:

  • Up to 2000 chemicals are used in textile processing, many of them known to be harmful to human (and animal) health.   Some of these chemicals evaporate, some are dissolved in treatment water which is discharged to our environment, and some are residual in the fabric, to be brought into our homes (where, with use, tiny bits abrade and you ingest or otherwise breathe them in).  A whole list of the most commonly used chemicals in fabric production are linked to human health problems that vary from annoying to profound.
  • The application of these chemicals uses copious amounts of water. In fact, the textile industry is the #1 industrial polluter of fresh water on the planet.[16] These wastewaters are discharged (largely untreated) into our groundwater with a high pH and temperature as well as chemical load.

Concerns in the United States continue to mount about the safety of textiles and apparel products used by U.S. consumers.  Philadelphia University has formed a new Institute for Textile and Apparel Product Safety, where they are busy analyzing clothing and textiles for a variety of toxins.  Currently, there are few regulatory standards for clothing and textiles in the United States.  Many European countries,  as well as Japan and Australia, have much stricter restrictions on the use of chemicals in textiles and apparel than does the United States, and these world regulations will certainly impact world production.

There is a bright spot in all of this:  an alternative to conventional textile processing does exist.  The new Global Organic Textile Standard (GOTS) is a  tool for an international common understanding of environmentally friendly production systems and social accountability in the textile sector; it covers the production, processing, manufacturing, packaging, labeling, exportation, importation and distribution of all natural fibers; that means, specifically, for example:  use of certified organic fibers, prohibition of all GMOs and their derivatives; and prohibition of a long list of synthetic chemicals (for example: formaldehyde and aromatic solvents are prohibited; dyestuffs must meet strict requirements (such as threshold limits for heavy metals, no  AZO colorants or aromatic amines) and PVC cannot be used for packaging).

A fabric which is produced to the GOTS standards is more than just the fabric:

It’s a promise to keep our air and water pure and our soils renewed; it’s a fabric which will not cause harm to you or your descendants.  Even though a synthetic fiber cannot be certified to  GOTS, the synthetic mill could adopt the same production standards and apply them.   So for step #2, the weaving of the fiber into a fabric, the best choice is to buy a GOTS certified fabric or to apply as nearly as possible the GOTS parameters.

At this point in time, given the technology we have now, an organic fiber fabric, processed to GOTS standards, is (without a doubt) the safest, most responsible choice possible in terms of both stewardship of the earth, preserving health and limiting toxicity load to humans and animals, and reducing carbon footprint – and emphasizing rudimentary social justice issues such as no child labor.

And that would be the end of our argument, if it were not for this sad fact:  there are no natural fiber fabrics made in the United States which are certified to the Global Organic Textile Standard (GOTS).  The industry has, we feel, been flat footed in applying these new GOTS standards.  With the specter of the collapse of the U.S. auto industry looming large, it seems that the U.S. textile industry would do well to heed what seems to be the global tide of public opinion that better production methods, certified by third parties, are the way to market fabrics in the 21st Century.


[1] Source: Energy Information Administration, Form EIA:848, “2002 Manufacturing Energy Consumption Survey,” Form EIA-810, “Monthly Refinery Report” (for 2002) and Documentatioin for Emissions of Greenhouse Gases in the United States 2003 (May 2005). http://www.eia.doe.gov/emeu/aer/txt/ptb1204.html

[2] Dev, Vivek, “Carbon Footprint of Textiles”, April 3, 2009, http://www.domain-b.com/environment/20090403_carbon_footprint.html

[3] Rupp, Jurg, “Ecology and Economy in Textile Finishing”,  Textile World,  Nov/Dec 2008

[4] Rose, Coral, “CO2 Comes Out of the Closet”,  GreenBiz.com, September 24, 2007

[5] U.S. Energy Information Administration, “International Energy Annual 2006”, posted Dec 8, 2008.

[6] Many discussions of energy used to produce fabrics or final products made from fabrics (such as clothing) take the “use” phase of the article into consideration when evaluating the carbon footprint.  The argument goes that laundering the blouse (or whatever) adds considerably to the final energy tally for natural fibers, while synthetics don’t need as much water to wash nor as many launderings.  We do not take this component into consideration because

  • it applies only to clothing; even sheets aren’t washed as often as clothing while upholstery is seldom cleaned.
  • is biodegradeable detergent used?
  • Is the washing machine used a new low water machine?  Is the water treated by a municipal facility?
  • Synthetics begin to smell if not treated with antimicrobials, raising the energy score.

Indeed, it’s important to evaluate the sponsors of any published studies, because the studies done which evaluate the energy used to manufacture fabrics are often sponsored by organizations which might have an interest in the outcome.  Additionally, the data varies quite a bit so we have adopted the values which seem to be agreed upon by most studies.

[7] Ibid.

[8] “Tesco carbon footprint study confirms organic farming is energy efficient, but excludes key climate benefit of organic farming, soil carbon”, Prism Webcast News, April 30, 2008, http://prismwebcastnews.com/2008/04/30/tesco-carbon-footprint-study-confirms-organic-farming%E2%80%99s-energy-efficiency-but-excludes-key-climate-benefit-of-organic-farming-%E2%80%93-soil-carbon/

[9] Fletcher, Kate, Sustainable Fashion and Textiles,  Earthscan, 2008,  Page 13

[10] “Why Natural Fibers”, FAO, 2009: http://www.naturalfibres2009.org/en/iynf/sustainable.html

[11] Ibid.

[12] Aubert, C. et al.,  (2009) Organic farming and climate change: major conclusions of the Clermont-Ferrand seminar (2008) [Agriculture biologique et changement climatique : principales conclusions du colloque de Clermont-Ferrand (2008)]. Carrefours de l’Innovation Agronomique 4. Online at <http://www.inra.fr/ciag/revue_innovations_agronomiques/volume_4_janvier_2009>

[13] International Trade Centre UNCTAD/WTO and Research Institute of Organic Agriculture (FiBL);    Organic Farming and Climate Change; Geneva: ITC, 2007.

[14] 24th session of the FAO Committee on Commodity Problems IGG on Hard Fibers of the United Nations

[15] “Improving profits with energy-efficiency enhancements”, December 2008,  Journal for Asia on Textile and Apparel,  http://textile.2456.com/eng/epub/n_details.asp?epubiid=4&id=3296

[16] Cooper, Peter, “Clearer Communication,” Ecotextile News, May 2007.





More reasons to find a replacement for polyester.

22 06 2009

plastic trap The mass of  debris in the photo is, apparently, a tiny part of what the Wall Street Journal reports is afloat in the Pacific.   Nobody really knows how big it is:   “Some say it is about the size of Quebec, or 600,000 square miles — also described as twice the size of Texas. Others say this expanse of junk swept together by currents is the size of the U.S. — 3.8 million square miles. Or, it could be twice that size.”

Called The Great Pacific Garbage Patch, it’s a mass of floating plastic.  Nobody seems to be able to agree on the size, or even whether the plastic is dangerous or serving a function.   Plastics can harm ocean birds and mammals who eat it, because they carry toxins, can pierce internal organs and can trick animals into thinking they are full. But hard numbers are tough to come by. “It’s so hard to say a bird died due to plastic in its stomach,” says Holly Bamford, director of the National Oceanic and Atmospheric Administration’s marine-debris program. “We have seen birds mature and live out their whole life, and necropsies show plastic in their stomach.”  On the other hand, David Karl, an oceanographer at the University of Hawaii, says that the plastics have a high concentration of microorganisims clinging to them which are producing oxygen.

Polyester, or PET, is  a major component of this trash because PET is the major component of beverage containers (like bottled water).  But most PET (60% of global production) is used to make fibers and textiles.  In addition to the fact that this polyester remains in our oceans and landfills for around 1,000 years, it’s a very expensive way to spend our energy resources:

Polyester production, running at around 50 million tons  per year, consumes about 104 million barrels of oil for production (and that doesn’t include the energy needed for transportation).

We have called for research into substitutes for polyester fabrics and still insist that we  (a people which have sent men to the moon, after all) should be able to find a substitute for our plastic obsession.  Recycled polyester seems to have been crowned the Queen of Green by decorative fabrics distributors because it is claimed that by recycling the polyester we can have a lighter footprint.  I’ve outlined our arguments against that in other posts, not least of which is the fact that there are no workable takeback programs in place.

The argument in favor of recycling is that if consumers have an “easy” way to recycle their plastic, and are educated and reminded on the need to do so, most will, resulting in a cleaner environment.   However, Americans recycle only about 20% of their plastic bottles – and this in a nation where it’s relatively easy to throw a used bottle into a recycling container.   What percentage of fabrics do you think will be torn off sofas or delivered to a recycling facility?  How many project managers will tear out banquettes and order the separation of the fabric from the wooden frame?

Add to those arguments the fact that there has been a history of corporations collecting plastics and sending them overseas to be processed, such as the famous case of Pepsi Cola exporting tons of PET bottles to India in the 1990s.  This case amounts to an indictment of much of what passes for recycling in the United States and elsewhere – putting the plastic waste out of sight, out of mind.  The plastics industry is exporting their waste to less industrialized countries, avoiding domestic regulations, avoiding community opposition to waste handling facilities, paying their workers pennies a day, and maintaining a “green” image at home.  People in developed countries can lower their ecological guilt by depending on environmental injustice in Asia.  This is not recycling; this is, at best, a type of reprocessing that delays the eventual dumping of the plastic.  And at worst it encourages consumers to buy more plastic because their environmental concerns are lessened by the promise that the goods are being recycled.





What is the energy profile of the textile industry?

16 06 2009

carbon_footprint

If you’ve been following along you’ll know we haven’t even reached the point where we begin weaving – everything up till now dealt only with producing the raw materials (the fiber) and spinning into yarn!

So, the yarns are at the mill.  And that’s the kicker: we’ve been talking about how much energy it takes to produce the various fibers – and it varies dramatically – but there is no dramatic difference in the amount of energy needed to weave fibers into fabric depending on fiber type.[1] The processing is generally the same whether the fiber is nylon, cotton, hemp, wool or polyester:

  • thermal energy required per meter of cloth is 4,500-5,500 Kcal and
  • electrical energy required per meter of cloth is 0.45-0.55 kwh. [2]

This translates into huge quantities of fossil fuels  –  both to create energy directly needed to power the mills, produce heat and steam, and power air conditioners, as well as indirectly to create the many chemicals used in production.  In addition, the textile industry has one of the lowest efficiencies in energy utilization because it is largely antiquated.

So let’s go with the energy used to produce one KG of fabric (which is 92 MJ per KG as the New Zeland Merino Wool LCA study found).   Keeping  the energy needed for production as a  constant the synthetic fabrics still top the list:

Embodied Energy in production of various fibers + processing:
energy use in MJ per KG of fiber: energy use in MJ per KG of fabric TOTAL energy use in MJ per KG of fabric to produce fiber + weave into cloth
flax 10 92 102
Cotton, convt’l. 55 92 147
wool 63 92 155
Viscose 100 92 192
Polypropylene 115 92 207
Polyester 125 92 217
acrylic 175 92 267
Nylon 250 92 342

 

That means that it takes 3,886 MJ of energy to produce 25 yards of nylon fabric, which is  about enough to cover one average sofa.  That compares to 1,158 MJ if the fiber you used was flax (linen).  To put that into perspective, 1 gallon of gasoline equals 131 MJ of energy; driving a Lamborghini from New York to Washington D.C. uses approximately 2266 MJ of energy.(4)

Textile_total_energy_input

In addition to the energy requirements for textile production,  there is an additional dimension to consider during processing:  environmental pollution.  Conventional textile processing is highly polluting:

  • Up to 2000 chemicals are used in textile processing, many of them known to be harmful to human (and animal) health.   Some of these chemicals evaporate, some are dissolved in treatment water which is discharged to our environment, and some are residual in the fabric, to be brought into our homes (where, with use, tiny bits abrade and you ingest or otherwise breathe them in).  A whole list of the most commonly used chemicals in fabric production are linked to human health problems that vary from annoying to profound.  And new research is linking many diseases and disorders to exposure to chemicals.  Through the new science of environmental health science, we are learning that exposure to toxic chemicals (at levels once thought to have been safe) is increasing the  chronic disease burden for millions of us.  For more information about this disturbing concept,  check out the National Institute of Environmental Health Sciences, part of the National Institutes of Health.
  • The application of these chemicals uses lots  of water. In fact, the textile industry is the #1 industrial polluter of fresh water on the planet.[3] These wastewaters are discharged (largely untreated) into our groundwater with a high pH and temperature as well as chemical load.  I wrote about a documentary which catalogues the ravages brought on by water pollution and how it impacts those downstream, called (interestingly enough), DOWNSTREAM.

We are all downstream.


[1] 24thsession of the FAO Committee on Commodity Problems IGG on Hard Fibers of the United Nations

[2] “Improving profits with energy-efficiency enhancements”, December 2008,  Journal for Asia on Textile and Apparel,  http://textile.2456.com/eng/epub/n_details.asp?epubiid=4&id=3296

[3] Cooper, Peter, “Clearer Communication,” Ecotextile News, May 2007.

(4)  from Annika Carlsson-Kanyama and Mireille Faist, 2001, Stockholm University Dept of Systems Ecology, htp://organic.kysu.edu/EnergySmartFood(2009).pdf

Embodied Energy in production of various fibers + processing:
beach image energy use in MJ per KG of fiber: energy use in MJ per KG of fabric TOTAL energy use in MJ per KG of fabric to produce fiber + weave into cloth
flax 10 92 102
Cotton, convt’l. 55 92 147
wool 63 92 155
Viscose 100 92 192
Polypropylene 115 92 207
Polyester 125 92 217
acrylic 175 92 267
Nylon 250 92 342




What about using organic fabrics in the carbon footprint calculation?

9 06 2009

I’m so glad you asked!

From the previous post I hope I made it clear that natural fibers (whether organic or conventionally produced) have a lighter footprint than do synthetics – both in terms of emissions of greenhouse gasses and in terms of energy needed to manufacture the fibers.  And natural fibers have the added benefits of being able to be degraded by microorganisims and composted,  and  also of sequestering carbon.  According to the United Nations, they’re also a responsible choice, because by buying natural fibers you’re supporting the economies of many developing countries and supporting the livelihoods of many low-wage and subsistence workers.  The United Nations has declared 2009 the Year of Natural Fibers and they have a great website if you’re looking for more information:  http://www.naturalfibres2009.org/en/index.html

Substituting ORGANIC fibers for conventionally grown natural fibers is not just a little better but lots better in all respects:  uses less energy for production, emits fewer greenhouse gases, and supports organic farming (which has myriad environmental, social and health benefits).  A study published by Innovations Agronomiques  (http://www.inra.fr/ciag/revue_innovations_agronomiques/volume_4_janvier_2009) found that fully 43% less greenhouse gasses are emitted per unit under organic agriculture than under conventional agriculture.  A study done by Dr. David Pimentel of Cornell University found that organic farming systems used just 63% of the energy required by conventional farming systems, largely because of the massive amounts of energy requirements needed to synthesize nitrogen fertilizers.  Further, it was found in controlled long term trials that organic farming adds between 100-400KG of carbon per hectare to the soil each year, compared to non-organic farming.  When this stored carbon is included in the carbon footprint calculation, it reduces total greenhouse gasses even further. The key lies in the handling of organic matter (OM): because soil organic matter is primarily carbon, increases in soil OM levels will be directly correlated with carbon sequestration. While conventional farming typically depletes soil OM, organic farming builds it through the use of composted animal manures and cover crops.

Slide1

Taking it one step further beyond the energy inputs we’re looking at, which help to mitigate climate change, organic farming helps to ensure other environmental and social goals:

  • eliminates the use of synthetic fertilizers, pesticides and genetically modified organisims (GMOs) which is not only an improvement in human health and agrobiodiversity but also for the associated off farm biotic communities
  • conserves water (making the soil more friable so rainwater is absorbed better – lessening irrigation requirements and erosion)
  • ensures sustained biodiversity
  • and compared to forests, agricultural soils may be a more secure sink for atmospheric carbon, since they are not vulnerable to logging and wildfire.

Agriculture is an undervalued and underestimated climate change tool that could be one of the most powerful strategies in the fight against global warming, according to Paul Hepperly, Rodale Institute Research Manager. The Rodale Institute Farming Systems Trial (FST) soil carbon data (which covers 30 years)  shows conclusively that improved global terrestrial stewardship–specifically including regenerative organic agricultural practices–can be the most effective currently available strategy for mitigating CO2 emissions. (http://www.rodaleinstitute.org/files/Rodale_Research_Paper-07_30_08.pdf

So just how much CO2 can organic farming take out of the air each year?  According to data from the Rodale Institute Farming Systems Trial (FST) :

  • If only 10,000 medium sized farms in the US converted to organic production, they would store so much carbon in the soil it would be equivalent to taking 1,174,400 cars off the road.
  • If we converted the U.S.’s 160 million acres of corn and soybeans to organic, we could sequester enough carbon to satisfy 73% of the Koyoto targets for CO2 reduction in the U.S.
  • Converting U.S. agriculture to organic would actually  wipe out the 1.5 trillion pounds of CO2 emitted annually and give us a net increase in soil carbon of 734 billion pounds.

carbon sequestratioon image 1

Paul Hepperly says that organic farming is a no brainer:  “Organic farming is not a technological fix, not an untried experiment that could have its own unforeseen consequences.” Instead, it may well be one of the most powerful tools we have in our fight against global warming that brings with it a wealth of other environmental benefits.





carbon footprints…

2 06 2009

Please be aware that our suggestions are just starting points for you to consider when looking at a fabric, because actually calculating a carbon footprint is very complex and time consuming.  Peter Tydemers, who is an ecological economist at Dalhousie University in Nova Scotia, has warned that many of the energy calculators we see should be taken with a pinch of salt – because every detail of where and how something is produced can change and therefore affect the outcome. For example, simply changing an animals feed can have an influence on its CO2 footprint. “It’s all very fluid”, he says, “There’s a tremendous hunger for these sorts of numbers and this has created the assumption that any existing figures are robust. They’re not.” We suggest that you examine carefully any studies to see the variables and the assumptions  made.  Something else to determine is who funded the study!  I was really perplexed to see a web site which had “data” on the energy used to create various fibers; the conclusions being drawn were just a bit outside the limits of any studies I had seen earlier.  But when I saw the industry group that funded the study it all became clear.

That being said, to begin to evaluate the carbon footprint of any fabric the first thing you have to do is  figure out what the fabric is made of  – the fiber.    The fiber tells you a lot about the energy needed to make the yarns, and then the fabric.  The energy needed to produce different fibers varies a lot.

To make it easy to compare the fibers, I”ll divide them into two types: “natural” (from plants, animals and – less commonly – minerals), and “synthetic” (man made)

For synthetics, it’s important to remember that most synthetic fibers  started as fossil fuel, an inherently non renewable resource.  Very high amounts of energy are needed to both extract the oil from the ground as well as to produce the polymers (as it is done under high temperatures).

For natural fibers you must look at field preparation, planting and field operations (mechanized irrigation, weed control, pest control and fertilizers (manure vs. synthetic chemicals)), harvesting and yields.  Synthetic fertilizer use is a major component of the high cost of conventional agriculture:  making just one ton of nitrogen fertilizer emits nearly 7 tons of CO2 equivalent greenhouse gases.

A study done by the Stockholm Environment Institute on behalf of the BioRegional Development Group  concludes that the energy used (and therefore the CO2 emitted) to create 1 ton of spun fiber is much higher for synthetics than for hemp or cotton:

KG of CO2 emissions per ton of spun fiber:

crop cultivation

fiber production

TOTAL

polyester USA

0.00

9.52

9.52

cotton, conventional, USA

4.20

1.70

5.89

hemp, conventional

1.90

2.15

4.10

cotton, organic, India

2.00

1.80

3.75

cotton, organic, USA

0.90

1.45

2.35

The table above only gives results for polyester; other synthetics have more of an impact:  acrylic is 30% more energy intensive in its production than polyester and nylon is even higher than that.

Not only is the quantity of GHG emissions of concern regarding synthetics, so too are the kinds of gasses produced during production of synthetic fibers.  Nylon, for example, creates emissions of Nitrous Oxide,  N2O, which is 300 times more damaging than CO2.[1] In fact, during the 1990s, N2O emissions from a single nylon plant in the UK were thought to have a global warming impact equivalent to more than 3% of the UK’s entire CO2 emissions.[2] A study done for the New Zealand Merino Wool Association shows how much more total energy is required for the production of  synthetics than any natural fibers:

Energy used in production of various fibers:

energy use in MJ perKG of fiber:
flax fibre (MAT)

10

cotton

55

wool

63

Viscose

100

Polypropylene

115

Polyester

125

acrylic

175

Nylon

250

SOURCE:  “LCA: New Zealand Merino Wool Total Energy Use”, Barber and Pellow,      http://www.tech.plym.ac.uk/sme/mats324/mats324A9%20NFETE.htm

Natural fibers, in addition to having a smaller carbon footprint in the production of the spun fiber, have the benefit of

  1. being able to be degraded by micro-organisms and composted; in this way the fixed CO2 in the fiber will be released and the cycle closed.  Synthetics do not decompose.
  2. sequestering carbon.  Sequestering carbon is the process through which CO2 from the atmosphere is absorbed by plants through photosynthesis and stored as carbon in biomass (leaves, stems, branches, roots, etc.) and soils.

As I said, looking at the production of the fiber is just the first part of the equation.  It is clear that, in terms of energy use and CO2 emissions, synthetics are  significantly higher in both cases than any natural fiber.  How the fibers are grown or managed also makes a huge contribution to energy use, and as you might have suspected, organic methods improve these results even more and widen the gap between synthetic and natural fibers.  That’s next week’s topic.


[1] “Tesco carbon footprint study confirms organic farming is energy efficient, but excludes key climate benefit of organic farming, soil carbon”, Prism Webcast News, April 30, 2008, http://prismwebcastnews.com/2008/04/30/tesco-carbon-footprint-study-confirms-organic-farming%E2%80%99s-energy-efficiency-but-excludes-key-climate-benefit-of-organic-farming-%E2%80%93-soil-carbon/

(2) Fletcher, Kate, Sustainable Fashion and Textiles,  Earthscan, 2008,  Page 13





Carbon footprint of the textile industry

25 05 2009

We’re starting a series of blogs on the carbon footprint of textiles.    Because it’s such a complex subject we’re breaking it into smaller portions, beginning with looking at the textile industry as a whole.   In other words, why the fuss over textiles?

Fabrics, believe it or not, have a large carbon footprint.  In other words, it takes a lot of energy to produce fabrics.  According to the U.S. Energy Information Administration, the U.S. textile industry is the 5th largest contributor to CO2 emissioins in the United States (after primary metals, nonmetallic mineral products, petroleum and chemicals).  In the developing world, where the textile industry represents a larger percentage of GDP and mills are often antiquated, the CO2 emissions are greater.

In fact, today’s textile industry is one of the biggest sources of greenhouse gasses on Earth, due to the huge size and scope of the industry as well as the many processes and products that go into the making of textiles and finished textile products. (See Vivek Dev, “Carbon Footprint of Textiles”, April 3, 2009, http://www.domain-b.com/environment/20090403_carbon_footprint.html)

Based on estimated annual global textile production of 60 billion kilogrms (KG) 0f fabric, the estimated energy and water needed to produce that 60 billion KG of fabrics boggles the mind:  1,074 billion KWh of electricity (or 132 million metric tons of coal) and between 6 – 9 trillion liters of water.

Fabrics have been the elephant in the room for too long.  Do we overlook them because they are almost always used as a part of a finished product, such as sheets, blankets, sofas, curtains, and of course clothing?  It’s estimated that clothing and textiles account for about one ton of the 19.8 tons of total CO2 emissions produced by each person in the U.S. in 2006 (see Jurg Rupp, “Ecology and Economy in Textile Finishing”, Textile World, Nov/Dec 2008).

In the U.K., the Carbon Trust, working with Continental Clothing, has developed the world’s first carbon label for clothing (http://www.environmentalleader.com/2009/03/27/uk-launches-first-carbon-footprint-label-for-retail-clothing/)  The new label will provide the carbon footprint of the garment, from raw materials and  manufacture to use and disposal.

carbon footprint label

carbon footprint label

The first point we want you to keep in mind is that the industry is huge, and because of its size it’s impacts are profound.  There is more to think about when buying a fabric than thread counts or abrasion ratings.