Fabric and your carbon footprint

3 10 2013

In considering fabric for your sofa, let’s be altruistic and look at the impact textile production has on global climate change.  (I only use the term altruistic  because many of us don’t equate climate change with our own lives, though there have been several interesting studies of just how the changes will impact us directly, like the one in USA Today that explains that wet regions will be wetter, causing flash flooding;  dry regions will get drier, resulting in drought. And  …  a heat wave that used to occur once every 100 years now happens every five years (1)).

Bill Schorr

Bill Schorr


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.[2]  And the US textile industry is small potatoes when compared with some other countries I could mention.  Last week we explained that a typical “quality” sofa  uses about 20 yards of decorative fabric, plus 20 yds of lining fabric, 15 yds of burlap and 10 yds of muslin, for a total of 65 yards of fabric – in one sofa.

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.[3] 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[4]

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. [5] By contrast, a person in Haiti produced a total of only 0.21 tons of total carbon emissions in 2006.[6]

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.   Not an easy thing to do!  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,  or synthetic.[7]

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 5.90
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

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 [8] 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 [9] 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.[10] 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.[11] 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.[12]

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.[13] 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.[14] 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.[15] 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. [16] 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.

(1)    http://www.usatoday.com/story/news/nation/2013/02/28/climate-change-remaking-america/1917169/

(2)    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

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

(4)    Rupp, Jurg, “Ecology and Economy in Textile Finishing”,  Textile World,  Nov/Dec 2008

(5)    Rose, Coral, “CO2 Comes Out of the Closet”,  GreenBiz.com, September 24, 2007

(6)     U.S. Energy Information Administration, “International Energy Annual 2006”, posted Dec 8, 2008.

(7)    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

  1. it applies only to clothing; even sheets aren’t washed as often as clothing while upholstery is seldom cleaned.
  2. is biodegradeable detergent used?
  3. Is the washing machine used a new low water machine?  Is the water treated by a municipal facility?
  4. 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.

(8)     Ibid.

(9)    “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/

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

(11) “Why Natural Fibers”, FAO, 2009: http://www.naturalfibres2009.org/en/iynf/sustainable.html

(12)  Ibid.

(13) 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>

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

(15) 24th session of the FAO Committee on Commodity Problems IGG on Hard Fibers of the United Nations

(16)  “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





GMOs and nanotechnology – hope for the future

6 06 2013

I ran into some interesting ideas that seem to display why we should not immediately discredit new science – like genetic engineering or nanotechnology – because it might well provide clues to how we can continue to live on this planet.  So rather than taking a global stand against GMOs or nanotechnology perhaps we should look at how the science is used.

Carbon dioxide (CO2)  – the natural gas that allows sunlight to reach the Earth -  also prevents some of the sun’s heat from radiating back into space, thus trapping heat and warming the planet. Scientists call this warming the greenhouse effect. When t­his effect occurs naturally, it warms the Earth enough to sustain life. In fact, if we had no greenhouse effect, our planet would be an average temperature of minus 22 degrees Fahrenheit (minus 30 degrees Celsius)[1].  My kids would love the skiing, but they’d be too dead to enjoy it.  So carbon dioxide and the greenhouse effect are necessary for Earth to survive. But human inventions like power plants and cars, which burn fossil fuels, release extra CO2 into the air. Because we’ve added (and continue to add) this carbon dioxide to the atmosphere, more heat is stored on Earth, which causes the temperature of the planet to slowly rise, a phenomenon called global warming.

Carbon dioxide isn’t the only greenhouse gas (GHG) – others include water vapor, methane, nitrous oxide, hydrofluorocarbons, perfluorocarbons and sulfur hexafluoride – but it’s the most important.  And it’s going up as a direct result of human activity.[2]  Just recently, we passed a milestone that climate scientists have warned is impressively scary – for the first time in human history, atmospheric carbon dioxide levels will surpass 400 ppm.[3]

So what to do? Traditionally, we’ve relied on natural systems to deal with this extra CO2 – like trees and other plants which soak up the stuff through photosynthesis.  But the amounts being generated exceed the capacity of natural systems to deal with it.  So we look to technological solutions, which basically consist of:  capture (i.e., trapping the gas at its emission source and then putting it someplace where it won’t escape) and geologic sequestration or storage (putting it someplace where it won’t escape.)  But I’m not a believer in these measures – after all, captured CO2 must be transported (by rail, truck or ship) to its final storage place.  And where is there a storage place that will not leak and can accommodate the 30 billion metric tons of CO2 we generate every year – without dire environmental consequences.

We have to look outside the box.  There have been many such ideas, from the more outlandish (i.e., create man-made volcanoes to pump sulfur dioxide into the atmosphere to block sunlight and cool the planet[4]) to several I’ve outlined below that just might help.  But they depend  on the use of GMO and nano science.

As Technology.org describes it:  “It is not widely appreciated that the most substantial process of carbon sequestration on the planet is accomplished by myriad marine organisms making their exoskeletons, or shells.   Shells are produced biologically from calcium and magnesium ions in sea water and carbon dioxide from the air, as it is absorbed by sea water. When the organisms die, their shells disintegrate and form carbonate sediments, such as limestone, which are permanent, safe carbon sinks.”[5]

from ecoco: sustainable design

from ecoco: sustainable design

By studying how sea urchins grow their own shells, scientists at Newcastle University in the UK have discovered a way to trap CO2 in solid calcium carbonate using nickle nanoparticles.  “It is a simple system,” said Dr Lidija Siller from Newcastle University. “You bubble CO2 through the water in which you have nickel nanoparticles and you are trapping much more carbon than you would normally—and then you can easily turn it into calcium carbonate.”[6]  Most carbon capture and storage programs must first trap the CO2 and then pump it into holes deep under ground, which is both expensive and has a high environmental risk.    Lead author, PhD student Gaurav Bhaduri, is quoted: “ [the nickel catalyst]  is very cheap, a thousand times cheaper than carbon anhydrase”.  The two researchers have patented the process and are looking for investors.

Meanwhile, MIT professor Angela Belcher, who had done her thesis on the abalone,   and graduate students Roberto Barbero and Elizabeth Wood are also looking into this.  They have  created a process that can convert carbon dioxide into carbonates that could be used as building materials. Their process, which has been tested in the lab, can produce about two pounds of carbonate for every pound of carbon dioxide captured.

Their process requires using genetically modified yeast.

Yeast don’t normally do any of those reactions on their own, so Belcher and her students had to engineer them to express genes found in organisms such as the abalone. Those genes code for enzymes and other proteins that help move carbon dioxide through the mineralization process.

The MIT team’s biological system captures carbon dioxide at a higher rate than other systems being investigated. Another advantage of the biological system is that it requires no heating or cooling, and no toxic chemicals.

Dr. Belcher has also used genetically modified viruses so they would have a binding affinity with carbon nanotubes – which allowed them to build a high-powered lithium ion battery cathode that could power a green LED.  Dr. Belcher thinks that she might one day drive a virus-powered car.

I think these two examples demonstrate that we should always keep an open mind.  And remember that it’s not always the science that’s causing a problem, but rather how we use it.  The idea that GMO seeds are intellectual property (owned largely by Monsanto) for example, is one of the wrong ways to use this technology.  But let’s not throw the baby out with the bath water.





Is biomass carbon neutral?

8 05 2012

Global climate change is the major environmental issue of current times. Evidence for global climate change is accumulating and there is a growing consensus that the most important cause is humankind’s interference in the natural cycle of greenhouse gases. (Greenhouse gases get their name from their ability to trap the sun’s heat in the earth’s atmosphere – the so-called greenhouse effect.)

CO2 emissions are recognized as the most important contributor to this problem. Since the turn of the 20th century the atmospheric concentration of greenhouse gases has been increasing rapidly, and the two main causes have been identified as:

  1. burning of fossil fuels and
  2. land-use change, particularly deforestation.

And now the world has discovered plants.  People seem to think there is some magic in nature – that they can keep taking and things will grow back.  We can buy “carbon offsets” to mitigate our guilt – trees planted to “offset” our energy consumption for, maybe, a plane ride to Hawaii.

Because the carbon emitted when plants are burned is equal to that absorbed during growing, it seems self-evident that biomass is a zero carbon (or carbon neutral) fuel.[1]  The thinking goes like this:  Plants are busy converting CO2 to stored (“sequestered”) carbon in their branches, roots, stems and leaves – so when that plant is burned, the carbon which is released (as CO2) is replaced by another plant which is busy sequestering that carbon.

Why is burning fossil fuel – which  also releases CO2 when burned  – not considered to be carbon neutral?  As far as I can tell, it’s a matter of definition.  Today, the definition of carbon neutral means that the greenhouse gases released  by burning fuel is the same or less than the carbon that was stored in recent history (translation = plants, which grow and mature within 100 years or so, i.e., “recent history”). Releasing carbon that was stored in ancient history, such as  burning fossil fuels (which comes from plant material millions of years old)  introduces extra carbon to the environment. Because fossil fuels contain carbon that was in the environment in ancient times, by burning fossil fuels we release greenhouse gasses that wouldn’t naturally be there!

That concept took off.  Beginning with the Koyoto Protocol, which overlooked reduction targets for biomass, others embraced the concept of using biomass as a carbon neutral fuel:  the EU Emissions Trading Scheme counts biomass as “carbon neutral” as do UK Building Regulations, the World Business Council for Sustainable Development and the World Resources Institute –  despite the recognition that this definition is problematic.[2]  Biomass burning is being ramped up all around the world in the name of green energy.

The concept of biomass as being carbon neutral is so popular that the European Union’s energy objectives for 2020 include the requirement that 20% of the total be from renewable sources, made up from biomass such as wood, waste and agricultural crops and residues.[3]  And the biomass industry in the US asked for an exemption from the Environmental Protection Agency’s greenhouse gas regulations because, it claims, biomass is carbon neutral.  In January 2011, the EPA gave them a 3 year exemption.

This loophole gives oil companies, power plants and industries that face tighter pollution limits a cheap means to claim reductions in greenhouse gas emissions. According to a number of studies, applying this incentive globally could lead to the loss of most of the world’s natural forests as carbon caps tighten.  A very frightening scenario indeed, since deforestation is responsible for up to 20% of the world’s greenhouse gas emissions – more than all cars, trains, planes, boats and trains in the world combined. [4]

I found a great blog post on this subject by Jeff Gibbs on Huffington Post Green, and I’ve relied on it for much of this post.  Here are just two of the issues:

Issue 1:  “Trees not harvested will eventually die and be decomposed by insects, fungi, bacteria, and other microorganisms which will release all the carbon dioxide that burning would. This cycling process has been going on for half a billion years, long before humans had a hand in it, and will continue with or without us.”

Here’s what Jeff Gibbs has to say:

  • “Actually nature has plans for that dead tree. For one it’s food for the next generation of forest life. And it turns out trees are pretty good at transferring their CO2 to the soil rather than the atmosphere when they fall over dead. Underground roots of mushrooms called mycorrhiza digest the wood and keeps the carbon the trees had sucked from the air in the forest soil.   The proof? It’s called coal.  Millions of generations of plants and trees have taken in carbon from the air and deposited it as mountains of coal. It’s what trees and plants do. Because trees and plants took the CO2 out of the atmosphere we have the nice comfortable climate we enjoy today. It’s not their fault we’re releasing everything they worked so hard to lock away, and if we cut then down they are going to have that much more difficult of a time soaking the carbon back up.”

Issue 2:  “Carbon dioxide –  released by burning biomass – is carbon dioxide that was taken from the air as the trees grew, and the trees that replace the harvested biomass will grow by taking in carbon dioxide again.”

This is so fraught with different issues that we have to break it down into manageable segments to understand why this is not as simple as it seems:

  1.   When you cut down a fully mature, multi-ton tree, how long do you think it will be before the one-ounce sapling that replaces it will be able to replicate the carbon uptake of the multi-ton tree?  Some trees take 100 years or more to mature.  When burned for energy, a mature tree (80-100 years old) takes minutes to release its full load of carbon into the atmosphere, but its replacement, if grown, takes a full century to re-sequester that carbon. For those 100 years, the CO2 is still aloft in the atmosphere helping push the climate toward the point of dangerous change, and yet carbon accounting rules treat it as non-existent.  After the initial release of carbon sequestered in a standing forest, a well-managed forest will start re-growing and at some point in time will achieve approximately the same concentration of carbon sequestration as the original forest.  But during that time, the atmospheric concentration of heat trapping gasses has been higher than it would otherwise have been, increasing associated environmental damages, and we have foregone the sequestration that would have happened in the original forest![5]
  2.  Chopping down forests to burn for ethanol production — even if replanted as tree plantations — is like biting the hand that feeds you. “Natural forests, with their complex ecosystems, cannot be regrown like a crop of beans or lettuce,” reports the nonprofit Natural Resources Defense Council (NRDC), a leading environmental group. “And tree plantations will never provide the clean water, storm buffers, wildlife habitat and other ecosystem services that natural forests do.”[6]
  3.  Recent studies show that there is more biomass contained IN the soil than in what grows ON the soil above ground.   This soil carbon can be disturbed and released by harvesting and reforestation activities.[7]
  4.  In a study published by the Manomet Center for Conservation Sciences, it was found that burning  trees emits about 30% more carbon pollution than coal, which the report calls the “carbon debt” of biomass. [8]   According to the study,  under normal forest management   it takes over 21 years just to re-absorb the extra pollution that is released in the first year of burning the wood.    Also, the energy content of biomass is about 40% lower than that of regular fossil fuels, so you need to burn more of it to get the same power, which means more CO2. (to read more about this, click here.)
  5.  It is simply not possible to plant sufficient numbers of trees to deal with the increased carbon dioxide emissions that are expected over the next half century.  According to Harpers Index, the number of years the United States could meet its energy needs by burning all its trees is … 1.
  6.  Recent evidence suggests that global warming itself is stressing ecosystems and turning forests and forest soils into failing forests and, in the long run, into net sources of CO2. Thus, if we don’t curb our use of fossil fuels, it won’t matter how many trees we plant because these forests will be overcome and die as the climate continues to warm.[9]
  7.  Old-growth forests are often replaced by tree-farm plantations that are heavily managed (including with chemicals and fossil fuel-intensive machinery) and do not offer the same biodiversity benefits as natural forests.
  8.  Investment in forestry offsets does not contribute to reducing society’s dependence on fossil fuels, something that is ultimately needed to address climate change. Responding to climate change means fundamentally changing the way we produce and use energy.
  9.  All biomass is not created equal.  According to Jeff Gibbs, some biomass plants burn old tires; others shovel in old houses and creosote soaked railroad ties. I don’t know what’s “bio” about all this but the energy you get is considered carbon neutral and renewable.

Here are Jeff Gibb’s seven truths that the Lorax would have us remember:

  1. Saving our forests (and that doesn’t mean more tree plantations) is the best way to stop global warming and save humanity.
  2. Deforestation is just as likely to result in the end of humanity as climate change and it’s right on track to do so.
  3. Burning things is the most insane way to stop global warming since doctors drilled holes in skulls to let the demons out and gave you a bill for it.
  4. There is no extra in nature and there is not enough “bio” on the planet to be burned, turned to ethanol, biodiesel or jet fuel, or bio-charcoal.
  5. Woody biomass falsely deemed renewable energy increases the CO2 in the atmosphere, destroys forests, and prevents renewables from being fully explored.
  6. Geo-engineering the forests, atmosphere or oceans to stop global warming isn’t going to work. We can’t even figure out how to stop carp from taking over a river or bugs from eating a forest.
  7. There is a possibility that the only way to heal the planet is to get control of our own numbers and consumption while letting nature do the work she has done for three billion years: run the planet.

[2] Johnson, Eric, “Goodbye to carbon neutral:  Getting Biomass footprints right”, Atlantic Consulting, Gattikon, Switzerland, November 2008.

[3] Neslan, Arthur, Guardian Environment Network, April 2, 2012. http://www.guardian.co.uk/environment/2012/apr/02/eu-renewable-energy-target-biomass

[4] Greenpeace, “Solutions to Deforestation”;  http://www.greenpeace.org/usa/en/campaigns/forests/solutions-to-deforestation/

[5] Natural Resrouces Defense Council comments with respect to draft Policy DAR-12, June 17, 2010.

[8] “Biomass Sustainability and Carbon Policy Study”, Manomet Center for Conservation Sciences, June 2010

[9] David Suzuki Foundation, Ibid.





Climate change and extreme weather

23 04 2012

I just saw this powerful video based on a recent editorial by Bill McKibben  in the Washington Post on May 23, 2011.   Narritation is  by Stephen Thomson of Plomomedia.com, who accompanies the piece with striking footage of the events Bill wrote about.





Estimating the carbon footprint of a fabric

19 01 2011

We published this blog almost two years ago, but the concepts haven’t changed and we think it’s very important.   So here it is again:

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 5.90
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

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.





Volatile Organic Compounds (VOCs)

17 03 2010

What are Volatile Organic Compounds (VOC’s) that we hear so much about?

Simply, they are chemicals which are carbon-based (hence the “organic” in the name, as organic chemistry is the study of carbon containing compounds) and which volatilize – or rather, evaporate or vaporize – at ordinary (atmospheric) temperatures.  This is a very broad set of chemicals!

These volatile organic compounds (VOC’s) are ubiquitous in the environment.  You can’t see them, but they’re all around us.  They’re not  listed as ingredients on the products you bring home, but they’re often there.   The most common VOC is methane, which comes from wetlands and rice agriculture to …well, “ruminant gases” (or cow farts – which are actually not a trivial consideration:  cows are responsible for 18% of all greenhouse gasses – read more here).  We ourselves contribute to CO2 emissions each time we breathe out.  They’re also in paint, carpets, furnishings, fabrics and cleaning agents.

The evaporating chemicals from many products contribute to poor indoor air quality, which the U.S. Environmental Protection Agency estimates is two to five times worse than air outside – but concentrations of VOC’s can be as much as 1,000 times greater indoors than out.  These chemicals can cause chronic and acute health effects, while others are known carcinogens.   Hurricane Katrina proved a lesson in what happens when we don’t pay attention to indoor air quality:  The trailers which were provided to refugees of Katrina proved, in a test done by the Centers for Disease Control and Prevention, to have formaldehyde levels that were 5 times higher than normal; with some levels as high as 40 times higher.  Other airborne contaminants were found to be present.  The result? This is from Newsweek, November 22, 2008:

”  …the children of Katrina who stayed longest in ramshackle government trailer parks in Baton Rouge are “the sickest I have ever seen in the U.S.,” says Irwin Redlener, president of the Children’s Health Fund and a professor at Columbia University’s Mailman School of Public Health. According to a new report by CHF and Mailman focusing on 261 displaced children, the well-being of the poorest Katrina kids has “declined to an alarming level” since the hurricane. Forty-one percent are anemic—twice the rate found in children in New York City homeless shelters, and more than twice the CDC’s record rate for high-risk minorities. More than half the kids have mental-health problems. And 42 percent have respiratory infections and disorders that may be linked to formaldehyde…”

There is no clear and widely supported definition of a VOC.   Definitions vary depending on the particular context and the locale.  In the U.S., the EPA defines a VOC as any compound of carbon (excluding carbon monoxide, carbon dioxide, carbonic acid, metallic carbides or carbonates  and ammonium carbonate)  which reacts with sunlight to create smog  –   but also includes a list of dozens of exceptions for compounds “determined to have negligible photochemical reactivity.” 

Under European law, the definition of a VOC is based on evaporation into the atmosphere, rather than reactivity, and the British coatings industry has adopted a labeling scheme for all decorative coatings to inform customers about the levels of organic solvents and other volatile materials present. Split into five levels, or “bands”, these span minimal, low, medium, high, and very high.

These differences in definition have led to a lot of confusion.  Especially in the green building community, we think of VOCs as contributors to indoor air quality (IAQ) problems—and the amount of VOCs is often our only IAQ metric for a product. But there are lots of compounds that meet a chemist’s definition of VOC   but are not photoreactive (as in the EPA definition)  so are not defined as VOCs by regulators. Some of these chemicals—including formaldehyde, methyl chloride, and many other chlorinated organic compounds—have serious health and ecological impacts.  Manufacturers can advertise their products as being “low-VOC” – while containing extremely toxic  volatilizing chemicals, such as perchloroethane in paint, which is not listed as a VOC by the EPA and therefore not required to be listed!

The Canadian government  (bless em) has an extensive list of which chemicals are considered VOC’s and you can access it here.  When products are identified as to which might contain VOC’s, furnishings are often cited and formaldehyde is the chemical highlighted, because it’s the chemical used most widely in fabric finishes.  However, there are many other chemicals on the list which are used in textile production, such as benzenes and benzidines;  methylene chloride, tetrachloroethylene, toluene and pentachlorophenol.

Some manufacturers advertise the amount or type of VOC in their products – and that may or may not be a good indication of what is actually released into the air, because sometimes these chemicals morph into something new as they volatilize.  The key word to remember is: reactive chemistry.  The chemicals don’t exist in a vacuum – heat, light, oxygen and other chemicals all have an effect on the chemical.

VOC’s are also found in our drinking water – the EPA estimates that VOC’s are present in 1/5 of the nation’s water supplies.  They enter the ground water from a variety of sources  – from textile effluents to oil spills.  The EPA lists VOC’s currently regulated in public water supplies (see that list here); they have established a maximum contaminant level (MCL) for each chemical listed.  But little is known about the additive effects of these chemicals.

Another point to remember is that the evaporation doesn’t happen in a pouf!  Chemicals evaporate over time – sometimes over quite long periods of time.  The graph below is of various evaporating chemicals at ground zero (GZ)  of the World Trade Center after the September 11 attacks:

For indoor air quality purposes we should look to results from chamber testing protocols that analyze key VOC’s individually.  Most of these protocols – such as California’s Section 01350, GreenGuard for Children and Schools, Indoor Advantage Gold and Green Label Plus – reference California’s list of chemicals for which acceptable exposure limits have been established.  But even this is not a comprehensive list.

Indoor air quality is certainly important, but in the case of fabrics there are many chemicals used in production which do not volatilize and which are certainly not beneficial to human health!  These include the heavy metals used in dyestuffs and many of the polymers (such as PVC).  So VOC considerations are just one part of the puzzle in evaluating a safe fabric.





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.





Organic agriculture and climate change

29 07 2009

global6

The debate over sustainable agriculture has gone beyond the health and environmental benefits that it could bring in place of conventional industrial agriculture. For one thing, conventional industrial agriculture is heavily dependent on oil, which is running out; and it is getting increasingly unproductive as the soil is eroded and depleted. Climate change will force us to adopt sustainable, low input agriculture to ameliorate the worst consequences of conventional agriculture, and to genuinely feed the world.

And climate change is upon us.  I’m sitting in Seattle experiencing an “historic heat wave” while reading that the Hadley Center of the British Meteorological Organization has said the world’s temperature will increase by 8.8 degrees F rather than 5.8 degrees F this century.

The Inter-Governmental Panel on Climate Change (IPCC) has said we can expect a considerable increase in heat waves, storms, floods, and the spread of tropical diseases into temperate areas, impacting  the health of humans, livestock and crops. It also predicts a rise in sea levels up to 35 inches this century, which will affect something like 30% of the world’s agricultural lands (by seawater intrusion into the soils underlying croplands and by temporary as well as permanent flooding). If the Hadley Center is right, the implications will be even more horrifying: Melting of the Antarctic, the Arctic, and especially the Greenland ice-shields is occurring far more rapidly than was predicted by the IPCC. This will reduce the salinity of the oceans, which in turn  weakens (if not diverts) oceanic currents such as the Gulf Stream from their present course . And if that continues, it would eventually freeze up areas that at present have a temperate climate, such as Northern Europe.

According to the Institute of Science in Society, “It is becoming clear that climate change and its different manifestations (as mentioned above) will be the most important constraints on our ability to feed ourselves in the coming decades. We cannot afford to just sit and wait for things to get worse. Instead, we must do everything we can to transform our food production system to help combat global warming and, at the same time, to feed ourselves, in what will almost certainly be far less favorable conditions.”

But before we tackle the question of how best to feed ourselves during these “less favorable” times: how can organic agriculture help with global warming?

It’s generally assumed that various Greenhouse Gases (GHG) are responsible for
global warming and climate change.   On a global scale, according to a study commissioned by IFOAM, agriculture has been responsible for approximately 15% of all GHG emissions:

  • 25% of all CO2 emissions come from agriculture
  • 60% of CH4 (methane) emissions come from agriculture
  • 80% of N2O (nitrous oxide) emissions  come from agriculture

About 60% of the CO2 emissions from human and animal activities is absorbed by the oceans and plants; the remaining 40% builds up in our atmosphere.    So what to do about the 40% that’s building up in our atmosphere?  Where can it be stored?

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In  looking at ways to “defuse” this CO2 build up, scientists began looking at carbon “sinks”.  Carbon sinks are natural systems that suck up and store carbon dioxide from the atmosphere. The main natural carbon sinks are plants, the ocean and soil. Plants grab carbon dioxide from the atmosphere to use in photosynthesis; some of this carbon is transferred to soil as plants die and decompose. The oceans are a major carbon storage system for carbon dioxide. Marine animals also take up the gas for photosynthesis, while some carbon dioxide simply dissolves in the seawater.

Initially forests were thought to be the most efficient way to sequester (or absorb) this carbon.  It was thought that escalating fossil fuel consumption could be balanced by vast forests breathing in all that CO2.   But  these sinks, critical in the effort to soak up some of our greenhouse gas emissions, may be maxing out, thanks to deforestation, and human-induced weather changes that are causing the oceanic carbon dioxide “sponge” to weaken.

New data is beginning to show that it may be that the soil itself makes more of a difference (in terms of carbon sequestration)  than what’s growing on it.  On a global scale, soils hold more than twice as much carbon as does vegetation (1.74 trillion tons for soil vs. 672 billion tons for vegetation) – and more than twice as much as is contained in our atmosphere.

The Rodale Institute Farming Systems Trial (FST), launched in 1981, is a 12 acre side by side experiment comparing three agricultural management systems: one conventional, one legume-based organic and one manure-based organic.  In 23 years of continuous recordkeeping,  the FST’s two organic systems have shown an increase in soil carbon of 15 – 23%, with virtually no increase in non-organic systems.

carbonsoil

This soil carbon data  shows  that improved global terrestrial stewardship–specifically including regenerative organic agricultural practices–can be the most effective currently available strategy for mitigating CO2 emissions. [2]

But although it is well established that organic farming methods sequester atmospheric carbon, researchers have yet to flesh out the precise mechanisms by which this takes place.   One of the keys seems to be in the handling of organic matter – while conventional agriculture typically depletes organic matter, organic farming builds it thru the use of composed animal manures and cover crops.  In the FST, soil carbon levels increased more in the manure-based organic system than in the legume-based organic system, presumably because of the incorporation of manures, but the study also showed that soil carbon depends on more than just total carbon additions to the system–cropping system diversity or carbon-to-nitrogen ratios of inputs may have an effect. “We believe that the differences in decay rates [of soil organic matter] have a lot to do with it,” says Hepperly, since “soluble nitrogen fertilizer accelerates decomposition” in the conventional system.

The people at Rodale put the carbon sequestration argument into an equivalency we can all understand: think of it in terms of the number of cars that would be taken off the road each year by farmers converting to organic production.  Organic farms sequester as much as 3,670 pounds of carbon per acre-foot each year. A typical passenger car, according to the EPA, emits 10,000 pounds of carbon dioxide a year (traveling an average of 12,500 miles per year). Here’s how many cars farms can take off the road by transitioning to organic:  car

U.S. agriculture as currently practiced emits a total of 1.5 trillion pounds of CO2 annually into the atmosphere. Converting all U.S. cropland to organic would not only wipe out agriculture’s massive emission problem, but by eliminating energy-costly chemical fertilizers, it would actually give us a net increase in soil carbon of 734 billion pounds.

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.  In addition to emitting fewer GHGs while sequestering carbon, organic agriculture uses less energy for production.  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.

Taking it one step further beyond the energy inputs we’re looking at, which help to mitigate climate change, organic farming:

  • eliminates the use of synthetic fertilizers, pesticides and genetically modified organisms (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 production has a strong social element and includes many Fair Trade and ethical production principles.  As such it can be seen as more than a set of agricultural practices, but also as a tool for social change.[3] For example, one of the original goals of the organic movement was to create specialty products for small farmers who could receive a premium for their products and thus be able to compete with large commercial farms.

And actually, it seems that modern industrial agriculture is on the way out.  The Food and Agriculture Organization of the United Nations (FAO) admitted in 1997 that wheat yields in both Mexico and the USA had shown no increase in 13 years  – blamed on the fact that fertilizers are becoming  less and less effective, as are pesticides.   The farmers are losing the battle.  Conventional agrochemical use (which includes many highly toxic substances) also has many immediate human impacts:  documented cases of short term illnesses, increased medical costs and the build up of pesticides in human and animal food chains.  The chemicals also contaminate the drinking and ground water.  And industrial agriculture is far too vulnerable to shortages in the availability of fuel and to increases in the price of oil.

That’s a lot to think about when looking for your next T shirt, so before you plunk down your money for another really cool shirt,  think about what you  will be getting in exchange.


[1] I should point out that although “sinks” in vegetation and soils  have a high
potential to mitigate increases of CO2 in the atmosphere, they are not
sufficient to compensate for heavy inputs from fossil fuel burning.  The long-term solution to global warming is simple:  reduce our use of fossil fuel, somehow, anyhow!
Yet the contribution from agriculture  could buy time during which
alternatives to fossil fuel can take affect – especially if that agricultural system is organic.

[2] http://www.rodaleinstitute.org/files/Rodale_Research_Paper-07_30_08.pdf

[3] Fletcher, Kate, Sustainable Fashion and Textiles, p. 19





Cotton is a good way to buy oil.

21 07 2009

Provocative title, isn’t it?  But I didn’t say it, the statement comes from Jim Rogers, one of the world’s most successful investors and co-founder of the Quantum Fund (with George Soros) from which he retired in 1980.  Since then he has been a college professor, world traveler, author, economic commentator and creator of the Rogers International Commodities Index.  And now, Jim Rogers says he’s investing in agriculture.

Jim Rogers is looking at cotton as a commodity (and an investment strategy), based on the fact that almost everything has some dependence on energy prices, based on  the embodied energy of the product.  He bases his decision on the fact that so many textiles today are made from synthetics – which come from oil.  Since the price of oil is going up (and will likely continue to go up) the price of synthetics is also going up.  So textile makers are reverting to natural fibers.  Cotton is the most popular natural fiber in the world, and the cotton – oil connection is both direct (through the use of synthetic fertilizers and pesticides), and indirect  (land formerly used to grow cotton can be shifted to other production to feed ethanol demand).  As Jim Rogers says,  “I hadn’t thought of this cotton-oil connection before, and it’s drawing these connections before others do that makes a great investor.”

If we are going to “reduce our dependence on foreign oil” (as the government likes to put it), shouldn’t we be looking at agriculture?  Dr. Albert Bartlett, Professor Emeritus in Nuclear Physics at Colorado University, Boulder, has said that the definition of “modern agriculture is the use of land to convert petroleum into food”.

I checked the web – and agriculture is really an energy hog.  According to the website Food and Water Watch:

  • 20% of the fossil fuel used in the US goes toward food production.
  • This inefficient system spends 10,551 quadrillion joules of energy each year – about the same as used by all of France.
  • The US EPA reported that US agriculture is responsible for the same amount of CO2 emissions per year as 141,000,000 cars.  Emissions DOUBLE when electricity usage is included.

Kenneth Watt, on the very first Earth Day in 1970, said that our very existence is dependent on the massive import of energy into industrial agriculture from petroleum, natural gas and coal – and this massive energy use creates a “fossil fuel subsidy”:  that means the use of petroleum has enabled fewer farmers to produce much more food on less land, so the population can grow.

Petroleum-based agriculture has reduced the proportion of the US population engaged in agriculture from about 50% about 75 years ago to less than 2% today.  In other words, the average American farmer feeds lots of people, as well as having enough left over to ship abroad. Petroleum also lets Floridians eat salmon from Alaska, and Alaskans enjoy orange juice from Florida. Between 1950 and 1970, the last 11 million horses were taken out of American agriculture and replaced by tractors powered by crude oil. Since it takes very roughly four times the acreage to support one horse as a person, this means we have been able to add 44 million people to the American population [in those twenty years] for that one cause alone, because of a fossil fuel subsidy.

According to Kenneth Watt, “mankind is embarked on an absolutely immense gamble. We are letting the population build up and up and up, by increasing the carrying capacity of the Earth for people, using a crude-oil energy subsidy, on the assumption that there’s no inherent danger in this because when the need arises we’ll be able to get ultimate sources of energy.”

But what happens if we don’t have alternate sources of energy,  when the oil crunch appears?  As oil production declines, prices will rise – especially commodities – and most especially food.

So how can organic agriculture help us with this dire picture.  You’ll be surprised!  Check in next week.





Why is recycled polyester considered a sustainable textile?

14 07 2009

 

plastic_bottles

Synthetic fibers are the most popular fibers in the world – it’s estimated that synthetics account for about 65% of world production versus 35% for natural fibers.[1] Most synthetic fibers (approximately 70%) are made from polyester, and the polyester most often used in textiles is polyethylene terephthalate (PET).   Used in a fabric, it’s most often referred to as “polyester” or “poly”.

The majority of the world’s PET production – about 60% – is used to make fibers for textiles; about 30% is used to make bottles.   It’s estimated that it takes about 104 million barrels of oil for PET production each year – that’s 70 million barrels just to produce the virgin polyester used in fabrics.[2] That means most polyester – 70 million barrels worth –  is manufactured specifically to be made into fibers, NOT bottles, as many people think.  Of the 30% of PET which is used to make bottles, only a tiny fraction is recycled into fibers.  But the idea of using recycled bottles – “diverting waste from landfills” – and turning it into fibers has caught the public’s imagination.

The reason recycled polyester (often written rPET) is considered a green option in textiles today is twofold, and the argument goes like this:

  1. energy needed to make the rPET is less than what was needed to make the virgin polyester in the first place, so we save energy.
  2. And  we’re keeping bottles and other plastics out of the landfills.

Let’s look at these arguments.

1) The energy needed to make the rPET is less than what is needed to make the virgin polyester, so we save energy:

 

It is true that recycling polyester uses less energy that what’s needed to produce virgin polyester.  Various studies all agree that it takes  from 33%  to 53% less energy[3].  If we use the higher estimate, 53%,  and take 53% of the total amount of energy needed to make virgin polyester (125 MJ per KG of ton fiber)[4], the amount of energy needed to produce recycled polyester in relation to other fibers is:

Embodied Energy used in production of various fibers:

energy use in MJ per KG of fiber:

hemp, organic

2

flax

10

hemp, conventional

12

cotton, organic, India

12

cotton, organic, USA

14

cotton,conventional

55

wool

63

rPET

66

Viscose

100

Polypropylene

115

Polyester

125

acrylic

175

Nylon

250

rPET is also cited as producing far fewer emissions to the air than does the production of  virgin polyester: again estimates vary, but Libolon’s website introducing its new RePET yarn put the estimate at 54.6% fewer CO2 emissions.  Apply that percentage to the data from the Stockholm Environment Institute[5], cited above:

KG of CO2 emissions per ton of spun fiber:

crop cultivation

fiber production

TOTAL

polyester USA

0

9.52

9.52

cotton, conventional, USA

4.2

1.7

5.89

rPET

5.19

hemp, conventional

1.9

2.15

4.1

cotton, organic, India

2

1.8

3.75

cotton, organic, USA

0.9

1.45

2.35

Despite the savings of both energy and emissions from the recycling of PET, the fact is that it is still more energy intensive to recycle PET into a  fiber than to use organically produced natural fibers – sometimes quite a bit more energy.

2) We’re diverting bottles and other plastics from the landfills.

 

That’s undeniably true,  because if you use bottles then they are diverted!

But the game gets a bit more complicated here because rPET is divided into “post consumer” PET and “post industrial” rPET:  post consumer means it comes from bottles; post industrial might be the unused packaging in a manufacturing plant, or other byproducts of manufacturing.  The “greenest” option has been touted to be the post consumer PET, and that has driven up demand for used bottles. Indeed, the demand for used bottles, from which recycled polyester fibre is made, is now outstripping supply in some areas and certain cynical suppliers are now buying NEW, unused bottles directly from bottle producing companies to make polyester textile fiber that can be called recycled.[6]

Using true post consumer waste means the bottles have to be cleaned (labels must be removed because labels often contain PVC) and sorted.  That’s almost always done in a low labor rate country since only human labor can be used.   Add to that the fact that the rate of bottle recycling is rather low – in the United States less than 6% of all waste plastic gets recycled [7].  The low recycling rate doesn’t mean we shouldn’t continue to try, but in the United States where it’s relatively easy to recycle a bottle and the population is relatively well educated in the intricacies of the various resin codes, doesn’t it make you wonder how successful we might be with recycling efforts in other parts of the world?

pet-recycling-graph-2 SOURCE: Container Recycling Institute

There are two types of recycling:  mechanical and chemical:

    • Mechanical recycling is accomplished by melting the plastic and re-extruding it to make yarns.  However, this can only be done  few times before the molecular structure breaks down and makes the yarn suitable only for the landfill[8] where it may never biodegrade, may biodegrade very slowly, or may add harmful materials to the environment as it breaks down (such as antimony).  William McDonough calls this  “downcycling”.
    • Chemical recycling means breaking the polymer into its molecular parts and reforming the molecule into a yarn of equal strength and beauty as the original.  The technology to separate out the different chemical building blocks (called depolymerization) so they can be reassembled (repolymerization) is very costly and almost nonexistent.

Most recycling is done mechanically (or as noted above, by actual people). Chemical recycling does create a new plastic which is of the same quality as the original,  but the process is very expensive and is almost never done, although Teijin has a new program which recycles PET fibers into new PET fibers.

The real problem with making recycled PET a staple of the fiber industry is this:  recycling, as most people think of it, is a myth.  Most people believe that plastics can be infinitely recycled  – creating new products of a value to equal the old bottles or other plastics which they dutifully put into recycling containers to be collected. The cold hard fact is that there is no such thing as recycling plastic, because it is not a closed loop.  None of the soda and milk bottles which are collected from your curbside are used to make new soda or milk bottles, because each time the plastic is heated it degenerates, so the subsequent iteration of the polymer is degraded and can’t meet food quality standards for soda and milk bottles.  The plastic must be used to make lower quality products.  The cycle goes something like this:

  • virgin PET can be made into soda or milk bottles,
  • which are collected and recycled into resins
    • which are appropriate to make into toys, carpet, filler for pillows, CD cases, plastic lumber products,  fibers or a million other products. But not new soda or milk bottles.
  • These second generation plastics can then be recycled a second time into park benches, carpet, speed bumps or other products with very low value.
  • The cycle is completed when the plastic is no longer stable enough to be used for any product, so it is sent to the landfill
    • where it is incinerated (sometimes for energy generation, which a good LCA will offset)  -
    • or where it will hold space for many years or maybe become part of the Great Pacific Garbage Patch![9]

And there is another consideration in recycling PET:  antimony, which is present in 80 – 85% of all virgin PET[10], is converted to antimony trioxide at high temperatures – such as are necessary during recycling, releasing this carcinogen from the polymer and making it available for intake into living systems.

Using recycled PET for fibers also creates some problems specific to the textile industry:

  • The base color of the recycled polyester chips vary from white to creamy yellow, making color consistency difficult to achieve, particularly for the pale shades.  Some dyers find it hard to get a white, so they’re using chlorine-based bleaches to whiten the base.
  • Inconsistency of dye uptake makes it difficult to get good batch-to-batch color consistency and this can lead to high levels of re-dyeing, another very high energy process.  Re-dyeing contributes to high levels of water, energy and chemical use.
  • Unsubstantiated reports claim that some recycled yarns take almost 30% more dye to achieve the same depth of shade as equivalent virgin polyesters.[11]
  • Another consideration is the introduction of PVC into the polymer from bottle labels and wrappers.
  • Many rPET fibers are used in forgiving constructions such as polar fleece, where the construction of the fabric hides slight yarn variations.  For fabrics such as satins, there are concerns over streaks and stripes.

Once the fibers are woven into fabrics, most fabrics are rendered non-recyclable  because:

  • the fabrics almost always have a chemical backing, lamination or other finish,
  • or they are blends of different synthetics (polyester and nylon, for example).

Either of these renders the fabric unsuitable for the mechanical method of recycling, which cannot separate out the various chemicals in order to produce the recycled yarn; the chemical method could  -   if we had the money and factories to do it.

One of the biggest obstacles to achieving McDonough’s Cradle-to-Cradle vision lies outside the designers’ ordinary scope of interest – in the recycling system itself. Although bottles, tins and newspapers are now routinely recycled, furniture and carpets still usually end up in landfill or incinerators, even if they have been designed to be  recycled [12] because project managers don’t take the time to separate out the various components of a demolition job, nor is collection of these components an easy thing to access.

Currently, the vision that most marketers has led us to believe, that of a closed loop, or cycle, in which the yarns never lose their value and recycle indefinitely is simply that – just a vision.  Few manufacturers, such as Designtex (with their line of EL fabrics designed to be used without backings) and Victor Innovatex (who has pioneered EcoIntelligent™ polyester made without antimony),  have taken the time, effort and money needed to accelerate the adoption of sustainable practices in the industry so we can one day have synthetic fabrics that are not only recycled, but recyclable.


[1]“New Approach of Synthetic Fibers Industry”, Textile Exchange,  http://www.teonline.com/articles/2009/01/new-approach-of-synthetic-fibe.html

[2] Polyester, Absolute Astronomy.com: http://www.absoluteastronomy.com/topics/Polyester and Pacific Institute, Energy Implications of Bottled Water, Gleick and Cooley, Feb 2009, http://www.pacinst.org/reports/bottled_water/index.htm)

[3] Website for Libolon’s RePET yarns:  http://www.libolon.com/eco.php

[4] Data compiled from:  “LCA: New Zealand Merino Wool Total Energy Use”, Barber and Pellow,                                                                       http://www.tech.plym.ac.uk/sme/mats324/mats324A9%20NFETE.htm and  “Ecological Footprint and Water

Analysis of Cotton, Hemp and Polyester”, by Cherrett et al, Stockholm Environment Institute

[5] “Ecological Footprint and Water Analysis of Cotton, Hemp and Polyester”, by Cherrett et al, Stockholm Environment Institute

[6] The Textile Dyer, “Concern over Recycled Polyester”,May 13, 2008,

[7] Watson, Tom, “Where can we put all those plastics?”, The Seattle Times, June 2, 2007

[8] William McDonough and Michael Braungart, “Transforming the Textile Industry”, green@work, May/June 2002.

[9] See http://www.greatgarbagepatch.org/

[10] Chemical Engineering Progress, May 2003

[11] “Reduce, re-use,re-dye?”,  Phil Patterson, Ecotextile News, August/September 2008

[12] “Taking Landfill out of the Loop”, Sarah Scott, Azure, 2006








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