Biofuels: not so groovy after all
Bill WeinbergFrom World War 4 Report
Although still blind to the related human rights violations, the scientific community finally acknowledges that "biofuels" fuel deforestation—and thereby result in a net increase in greenhouse gas emissions. Here's the abstract of the story that appears in the Oct. 22 edition of Science, "Fixing a Critical Climate Accounting Error":
The accounting now used for assessing compliance with carbon limits in the Kyoto Protocol and in climate legislation contains a far-reaching but fixable flaw that will severely undermine greenhouse gas reduction goals. It does not count CO2 emitted from tailpipes and smokestacks when bioenergy is being used, but it also does not count changes in emissions from land use when biomass for energy is harvested or grown. This accounting erroneously treats all bioenergy as carbon neutral regardless of the source of the biomass, which may cause large differences in net emissions. For example, the clearing of long-established forests to burn wood or to grow energy crops is counted as a 100% reduction in energy emissions despite causing large releases of carbon.
The standard "does not count CO2 emitted from tailpipes and smokestacks when bioenergy is being used"? What's up with that? Turns out the folks who wrote the Kyoto Protocol just took the biofuel industry's word for it! From Reuters, Oct. 22:
U.S. ethanol industry group the Renewable Fuels Association said biofuels are by definition emissions neutral because their tailpipe carbon output is absorbed by growing plants.
A cute little propaganda scam, eh? Obviously panicked that their cover has been blown, Biomass Magazine quickly retorts:
Biofuels produced from biomass feedstocks (i.e. plant matter) are, by definition, carbon neutral because carbon dioxide tailpipe emissions from the combustion of biofuels are readily absorbed by growing plants. As such, the tailpipe emissions resulting from the use of a gallon of ethanol produced from corn grown on U.S. farmland are negated by the growing of the corn itself.
Yet, in a newly published article in Science, frequent biofuel critics Tim Searchinger, Dan Kammen, and others argue that this widely held scientific convention is erroneous. They argue that biofuels and other biobased energies should be accountable for the biogenic tailpipe and "smokestack" CO2 emissions that are absorbed by growing feedstocks and carbon emissions that could result from land clearing. The authors argue that existing and proposed regulations, such as the so-called U.S. cap and trade bill, create an accounting loophole that will lead to increased deforestation. They conceptually propose an unnecessary and impossible system that would trace actual flows of carbon.
However, the release of CO2 from recently living organisms has no overall effect on atmospheric CO2 levels and is therefore carbon neutral because atmospheric CO2 decreases when a plant photosynthesizes, then increases back to its initial level when that carbon (in the form of a biofuel) is burned and returned to the atmosphere. In this way, biofuels "recycle" organic carbon.
Now by what logical contortions do they conclude that "CO2 from recently living organisms has no overall effect on atmospheric CO2 levels"? And does a field of "biomass feedstocks" absorb as much carbon as a forest—putting aside the issues of biodiversity, watershed protection, cultural survival for indigenous forest-dwellers, etc.? Let's see what some other voices have to say on the question.
From the Union of Concerned Scientists:
Clearing mature forests and replacing them with fast-growing younger trees is not a solution. To be sure, younger trees draw carbon out of the atmosphere more quickly. But cutting down mature forests releases large quantities of CO2. And replacing natural forests with tree plantations destroys biodiversity—the web of life that supports and nourishes all plants and animals.
From the World Rainforest Movement:
Even if OECD countries are responsible for 77% of the world fossil fuel-related emissions of CO2...they advocate for a "solution" that consists on using the photosynthetic activity of tree leaves to capture CO2 and retain carbon in the wood. These so-called "carbon sinks" are fast-growing species' plantations to be installed in the South. The model is simple: the North will continue emiting CO2 to the atmosphere and the South will be responsible of capturing it throught the new installed "forest cover". They call it "joint implementation" and is the most recent argument used by plantation promoters to justify their activity. According to one calculation, 300 million hectares of fast-growing trees are required to absorb the annual global emissions of CO2 if the present rate of emissions continues, as is expected. There’s no scientific evidence of their efficiency, since their capacity to capture CO2 can be much influenced by climate change...
Such plantations have little in common with forests. Consisting of thousands or even millions of trees of the same species, bred for rapid growth, uniformity and high yield of raw material and planted in even-aged stands, they require intensive preparation of the soil, fertilisation, planting with regular spacing, selection of seedlings, mechanical or chemical weeding, use of pesticides, thinning, and mechanized harvesting... Industrial tree plantations have in many cases been preceded by firing or clearcutting of native forests and have therefore become a new and major cause of deforestation.
From the Global Justice Ecology Project:
The expansion of oil palm plantations usually takes place at the expense of transforming natural ecosystems, particularly tropical rainforests. This has disastrous consequences... [T]he destruction of the forest implies the release of carbon dioxide (CO2) - one of the greenhouse effect gases, whose accumulation in the atmosphere is responsible for global warming and subsequently climate change. Moreover, if a comparative assessment of CO2 is made between the two systems (forests and plantations), it will be seen that tropical forests, because of their complexity, store and absorb much more carbon than plantations.
If you folks at Biomass Magazine think you have persuasive answers to these arguments, we'd love to hear from you. Really.
See our last post on the climate crisis.
Etiquetas: Agrofuels, Bill Weinberg, Biofuels, Energy
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