Using Hemp to Halt Climate Change

October 25th, 2009 – The hemp plant can be used in thousands of different products, including large-scale things such as houses and cars. Hemp is also able to be made into smaller goods aswell, from health products to paints.

An extremely important goal that hemp must be applied to immediately is the reversal of global warming. Upon first hearing such a statement, it may seem ridiculous that one thing could solve a world problem. However, utilizing hemp on a massive scale could indeed achieve this objective.

To understand how hemp can stop global warming, you need to understand how climate change is occurring. Greenhouse gases, primarily carbon dioxide, build up in the atmosphere. This high concentration of gas traps heat inside the Earth, leading to a general increase in temperature.

The negative effects of the advanced stages of global warming would be devastating and destructive. We cannot afford to wait; we must act now to counter these horrible consequences.

When you are young, you learn that for plants to grow, they must photosynthesize. This involves taking CO2 from the air and converting it to oxygen. The nature of the hemp plant enables it to absorb incredible amounts of carbon dioxide from the atmosphere, much more than all other plants.

Hemp can not only absorb carbon dioxide, but it puts much of it into the soil. This not only permanently removes it from the atmosphere, but it enhances the soil. Few other plants actually leave the soil healthier after they have grown, rather than depleting it.

Not only is hemp effective at reversing global warming through its growth, but the processing of it into products is “green” as well. Hemp is especially efficient when it comes to paper. Essentially no chemicals are required, unlike the many toxic ones that are necessary for tree paper.

It is stunning to realize how amazing hemp is, yet it is still illegal. Is the human race really trying to kill itself? That is what it appears, being we have a truly miraculous resource almost literally right at our feet, and instead of embracing it, we destroy it. What kind of policy is that?

 

Hemp, and Lots of It, Could Be One Climate Solution

October 21, 2009 – In New Zealand, the tiny political party Aotearoa Legalise Cannabis Party (ALCP) promotes a platform that it says can “reverse” damaging climate change by planting hundreds of thousands of hectares of cannabis hemp, ALCP says, at a density of around 300 plants per square meter, to replace NZ’s energy and fuel needs.

Yes, it sounds far-fetched, especially since in the US farmers have labored long and hard to get lawmakers to stop confusing non-cannabis industrial hemp grown for its myriad uses in industrial fibers and foods with its cannabis cousin.

Longtime hemp activist Jack Herer is offering $100,00 to anyone who can disprove his hypothesis that hemp is a silver bullet for climate change. Here’s Herer:

“If all fossil fuels and their derivatives, as well as trees for paper and construction, were banned in order to save the planet, reverse the Greenhouse Effect and stop deforestation, then there is only one known annually renewable natural resource that is capable of providing the overall majority of the world’s paper and textiles; meet all of the world’s transportation, industrial and home energy needs, while simultaneously reducing pollution, rebuilding the soil and cleaning the atmosphere all at the same time. That substance is the same one that has done it before: Cannabis Hemp.”

Anyone who can prove this statement wrong is entitled to $US 100,000. http://www.jackherer.com/challenge.html

Herer’s mixing of cannabis hemp with industrial hemp is a little unfortunate, for according to Hemp Global Solutions, hemp could be a good short term climate tool, because the crop is rapid-growing for carbon dioxide uptake, less vulnerable to climate variations than agro-forestry, and might be a good cash crop for farmers. HGS calculates each ton of hemp grown represents 1.63 tons of CO2 absorption.

Whether in the U.S. the Industrial Hemp Farming Act of 2009 can come to a vote during this session is uncertain. But Jack Herer isn’t the only person to espouse hemp. Dr. Bronner’s president, David Bronner, is among a small group of hemp farmers hoping to get more coverage for the bill.

Eight states (including Oregon as the most recent) have allowed industrial (non cannabis) hemp research or production, but thus far implementation has been hampered by the Drug Enforcement Agency.

Bronner, whose company has used hemp oil in its products for over a decade, was arrested in Washington, DC last week for planting hemp on the DEA front lawn. He said he’d rather buy his hemp from U.S. farmers instead of importing it, and “save on both import and freight charges.”

Source.

 

The Science behind Carbon Dioxide Reduction with Hemp

September 28, 2009 – A realistic, globally scalable plan to transfer CO2 from the atmosphere into soil and raw materials is already available – it’s called industrial hemp…

Our basic premise is that hemp is far more productive than typical agro-forestry projects, producing annual, versatile biomass alongside more rapid CO2 uptake. It can produce a vast range of sustainable raw materials with an overall low environmental impact, as well as improving soil structure, using low fertilizer and no other chemical inputs (i.e. reduced agrochemical residues).

Hemp can be grown on existing agricultural land (unlike most forestry projects), and can be included as part of a farm’s crop rotation with positive effects on overall yields of follow on crops. This, along with super versatility in diverse soil conditions and climates, makes hemp cultivation a viable and genuine potential large scale contributor to GHG mitigation.

Replacing Unsustainable Raw Materials

The vast quantities of hemp derived products and raw materials created by large scale cultivation could replace many oil-based unsustainable products and materials, particularly in construction, locking in captured CO2 and creating secondary benefits to the global environment. In particular, hemp could be used to replace significant quantities of tree-derived products, allowing reduced use of existing tree populations, thus maintaining their CO2 uptake.

Hemp also produces much higher quantities of stronger and more versatile fibre than cotton, and many other fibre crops, which often have very high chemical residue and water footprints. Extra processing required by hemp is also at least partially offset by its recycling potential.
Carbon Absorption of Hemp – HGS Preliminary Conclusions

Our carbon uptake estimates are calculated by the examining the carbon content of the molecules that make up the fibres of the hemp stem. Industrial hemp stem consists primarily of Cellulose, Hemicellulose and Lignin, whose chemical structure, carbon content, (and therefore absorbed CO2) are shown in the following section:

* Cellulose, 70% of stem dry weight:

Fig 1: Chemical structure of Cellulose (Hon, 1996).

Cellulose is a homogeneous linear polymer constructed of repeating glucose units. The carbon content of cellulose accounts for 45% of its molecular mass.

* Hemicellulose, 22% of stem dry weight:

Fig 2 : Chemical structure of Hemicellulose (Puls and Schuseil, 1993).

Hemicellulose provides a linkage between cellulose & lignin. It has a branched structure consisting of various pentose sugars. Based on an example of hemicellulose structure like the acetylated xylan chain with ? – 1, 2 bond to 4 – O – methyl glucuronic acid & an ? – 1, 3 bond to L – arabinofuranose pictured above the carbon content of hemicellulose accounts for 48% of its molecular mass.

* Lignin, 6% of stem dry weight:

Fig 3. Chemical structure of Lignin (Hon, 1996).

Lignin is a strengthening material usually located between the cellulose microfibrils. The lignin molecule has a complex structure that is probably always is variable (3). Using the example above, the carbon content is calculated to be 40% of the molecular mass.

To summarise the above, one tonne of harvested stem contains:

0.7 tonnes of cellulose (45% Carbon)
0.22 tonnes of hemicellulose (48% Carbon)
0.06 tonnes of lignin (40% Carbon)

It follows that every tonne of industrial hemp stems contains 0.445 tonnes Carbon absorbed from the atmosphere (44.46% of stem dry weight).

Converting Carbon to CO2 (12T of C equals 44T of CO2(IPCC)), that represents 1.63 tonnes of CO2 absorption per tonne of UK Hemp stem harvested. On a land use basis, using Hemcore’s yield averages (5.5 to 8 T/ha), this represents 8.9 to 13.4 tonnes of CO2 absorption per hectare of UK Hemp Cultivation.

For the purposes estimation, we use an average figure of 10T/ha of CO2 absorption, a figure we hold to be a reasonably conservative estimate. This is used to predict carbon yields, but CO2 offsets will be based on dry weight yields as measured at the weighbridge.

The roots and leaf mulch (not including the hard to measure fibrous root material) left in situ represented approximately 20% of the mass of the harvested material in HGS’ initial field trials. The resulting Carbon content absorbed but remaining in the soil, will therefore be approximately 0.084 tonnes per tonne of harvested material. (42% w/w) (5).

Using Hemcore’s UK yield estimates (5.5 – 8 T/ha) this represents 0.46 to 0.67 tonnes of Carbon per hectare (UK) absorbed but left in situ after Hemp cultivation.

That represents 1.67 to 2.46 T/ha of CO2 absorbed but left in situ per hectare of UK Hemp Cultivation.

Final figures after allowing 16% moisture (Atmospheric ‘dry’ weight) are as follows:

CO2 Absorbed per tonne of hemp stem 1.37t
CO2 Absorbed per hectare (stem) (UK) 7.47 to 11.25t
CO2 Absorbed per hectare (root and leaf) UK) 1.40 to 2.06t

Hemp ‘Self Offsetting.’

According to Defra, UK Farming emits a total CO2 equivalent of 57 millions tonnes in GHG’s. UK agricultural land use is 18.5 million hectares. This amounts to an average of around 3.1 tonnes of CO2 per hectare total embodied emissions. As a low fertiliser and zero pesticide/herbicide crop, with little management input, the carbon emissions of hemp cultivation is well below the average. Therefore we can assume the matter remaining in soils roughly offsets the cultivation and management emissions.

References

1. Hon, D.N.S. (1996) A new dimensional creativity in lignocellulosic chemistry. Chemical modification of lignocellulosic materials. Marcel Dekker. Inc. New York.(5)

2. Puls,J., J. Schuseil (1993). Chemistry of hemicelluloses: Relationship between hemicellulose structure and enzymes required for hydrolysis. In: Coughlan M.P., Hazlewood G.P. editors. Hemicellulose and Hemicellulases. Portland Press Research Monograph, 1993. (5)

3. Bjerre, A.B., A.S. Schmidt (1997). Development of chemical and biological processes for production of bioethanol: Optimization of the wet oxidation process and characterization of products, Riso-R-967(EN), Riso National Laboratory, Roskilde, Denmark. (5)

4. Anne Belinda Thomsen, Soren Rasmussen, Vibeke Bohn, Kristina Vad Nielsen and Anders Thygese (2005) Hemp raw materials: The effect of cultivar, growth conditions and pretreatment on the chemical composition of the fibres. Riso National Laboratory Roskilde
Denmark
March 2005. ISBN 87-550-3419-5.

5. Roger M Gifford (2000) Carbon Content of Woody Roots, Technical Report N.7, Australian Greenhouse Office.

These figures do not include the additional carbon dioxide that is saved by substituting unsustainable raw materials, to end products derived from harvested hemp that effectively locks in CO2. Such products include, building materials, plastics, cosmetics, composite boards and insulation materials. According to Limetechnology Ltd, Hemcrete locks up around 110kg of CO2 per m3 of wall, compared to the 200kg of CO2 emitted by standard concrete. It also excludes the carbon savings of replacing tree-derived products and leaving trees to continue to absorb CO2

Accurate Validation

Biomass is produced by the photosynthetic conversion of atmospheric carbon. The carbon uptake of hemp can be accurately validated annually by calculations derived from dry weight yield. This yield is checked at the weighbridge for commercial reasons prior to processing.

Highly accurate figures for total biomass yield and carbon uptake can then be made, giving a level of certainty not available through any other natural carbon absorption process.

Sources: http://mrgreenbiz.wordpress.com/2009/09/28/hemp-co2-the-science/
http://www.hempglobalsolutions.com/science2.php