Wednesday, March 14, 2012


Synthetic X Organic Textiles

The textile industry, according to the U.S. Energy Information Administration, is the 5thlargest contributor to CO2 emissions in the United States, after primary metals, nonmetallic mineral products, petroleum and chemicals.[

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 andbetween 6 – 9 trillion liters of water.

 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]

The carbon footprint of various fibers varies a lot.

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.

For natural fibers you must look at field preparation, planting and field operations (mechanized irrigation, weed control, pest control and fertilizers (manure or synthetic), 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.

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
5.90
hemp, conventional
1.90
2.15
4.05
cotton, organic, India
2.00
1.80
3.80
cotton, organic, USA
0.90
1.45
2.35

Acrylic is 30% more energy intensive in its production than polyester [7] and nylon is even higher than that.

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



Natural Fibers decompose, while synthetic fibers do not.
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.


PRODUCTION ENERGY
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)

Organic fibers uses less energy for production, emits fewer greenhouse gases and supports organic farming. 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. 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.
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

WEAVING ENERGY

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. 

BUT, we have to consider 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.  • 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.

Organic Fibers 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.

At this point in time, given the technology we have now, an organic fiber fabric, processed to GOTS (Global Organic Textile Standard (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.

There are no natural fiber fabrics made in the United States which are certified to the Global Organic Textile Standard (GOTS).

In 2006, their work was published as the Global Organic Textile Standard (GOTS) , which has since evolved into the leading set of criteria in the field of organic textile processing.  A main achievement of this group was the ability to compromise and to find even consensus GOTS aims to define a universal standard for organic fabrics—from harvesting the raw materials, through environmentally and socially responsible manufacturing, to labeling—in order to provide credible assurance to consumers. Standards apply to fiber products, yarns, fabrics and clothes and cover the production, processing, manufacturing, packaging, labeling, exportation, importation and distribution of all natural fiber products.   GOTS provides a continuous quality control and certification system from field to shelf.  A GOTS certified fabric is therefore much more than just a textile which is made from organic fibers.

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