Comments on: Can Biofuels Be Made Sustainably?

By: tidal

tidal — Mon, 09 Jul 2007 14:15:33 +0000

Regarding sustainability of biofuels… thought this new paper germane:

“humans appropriated 24% of the Earth’s potential production” of primary biomass each year… “with such an already high human pressure on ecosystems, schemes to replace fossil fuels with biomass fuels should be approached cautiously”

“Quantifying and mapping the human appropriation of net primary production in the Earth’s terrestrial ecosystems”, is about to be published by the National Academy of Sciences.
http://www.pnas.org/misc/highlights.shtml#Humans
The full paper is available online now here: http://www.pnas.org/ cgi/ content/ abstract/ 0704243104v1

From the lay synopsis:
Measuring human appropriation of net primary production, the aggregate impact of land use on biomass available each year in ecosystems, is one way to quantify the effect that human dominance has on the biosphere. Human land use, such as planting crops, or harvesting, such as clearing forests, alters patterns and pathways of carbon captured by photosynthesis. A recent analysis by Helmut Haberl et al. shows that humans appropriate almost a quarter of the Earth’s photosynthetic production capacity in this way. Haberl et al. analyzed data on human land use and harvests from 161 countries, which represent 97% of the Earth’s landmass. The results showed that humans appropriated 24% of the Earth’s potential production. Over half of the impact is attributable to harvesting crops or other plants. According to the authors, no other single species has such a large impact on the Earth’s production. The authors caution that, with such an already high human pressure on ecosystems, schemes to replace fossil fuels with biomass fuels should be approached cautiously given their ability to impact the biosphere further.

By: Earl Killian

Earl Killian — Wed, 04 Jul 2007 20:09:00 +0000

In response to Jonas: I would say that the past damage of Europeans and North Americans is not justification for developing countries to commit future damage. Rather North America and Europe should take responsibility to undo the damage they have done, while others should avoid doing further damage. Thus NA and EU should eventually be called upon to have negative GJG emissions until such time that they have removed the GHG they put into the atmosphere. If developing countries use the NA/EU precedent to emit GHG, they are only making their lives even worse (e.g. China losing water, which is more important to its welfare than fossil fuels are).

For example, the US was responsible for 29% of GHG emissions from 1750 to 2005. Once we get to zero emissions, we should go negative until we’ve removed all that carbon from the atmosphere. That might be a long way away of course. China is only 8% of 1750-2005 GHG emissions, and so they will have a lot less cleanup to do. See http://tinyurl.com/2l7f8l for other nations.

By: Earl Killian

Earl Killian — Wed, 04 Jul 2007 19:41:19 +0000

You should be careful about over generalization. What is suggested (without being explicitly stated) is flawed logic:
* X is a biofuel
* X cannot be made sustainably
* Therefore biofuels cannot be made sustainably
In particular, the title reads “Can Biofuels Be Made Sustainably?” but the text talks about corn ethanol and soy and palm biodiesel, as if those encompass all biofuels.

There are real issues with most biofuels. That is true. But one should not generalize to all members of a class even if most members are bad. What about algae biodiesel, for example?

By: Joe

Joe — Tue, 03 Jul 2007 23:18:37 +0000

Fair enough, though it may just be an accident of history that what is threatened these da.ys is tropical forests — which are crucial carbon sinks far more important than forests in US and EU

By: Jonas

Jonas — Tue, 03 Jul 2007 22:29:12 +0000

Well, sustainability criteria are fine as long as they are not another unfair barrier to trade, killing developing countries who could be biofuel exporters.

Remember: everything that grows in the US and the EU used to be forest land. That was destroyed long ago and turned into agricultural land. 200 years later – after this destruction and massive use of fossil fuels allowed the West to become super-rich – we see this wealthy West imposing “sustainability criteria”.

To be fair, we should import moderately sustainable biofuels from the developing world, and at least compensate developing countries for avoiding deforestation.

If we don’t, we are hypocrits. We have built our wealth (which allows us to organise think tanks on “sustainability” and blogs about climate change) on the destruction of our own forests, and on that of others (when we were still ruling our colonies).

We need a historic perspective on sustainability.