[permaculture] Re: Bio diesel (Not Bio gas)
mpludwig at facstaff.wisc.edu
Thu Mar 7 11:15:15 EST 2002
At 04:02 PM 3/6/02 -0800, you wrote:
>I don't consider myself an expert on this by any means, but I have a few
>questions about plant based substitutes for petroluem based fuels. I call
>them questions, rather than criticisms, because I am open to information
>that helps me see through what otherwise seems problematic to me now. I'd
>love to find out that there are good alternatives, so please feel free to
>fill me in if I'm missing something.
Shooting from the hip here....
>I see the advantage of a fuel that can be grown annually rather than pumped
>from the ground and created on the scale of millions of years. But this is
>not the only goal of a sustainable fuel source.
>Is there a qualitative difference in the exhaust between diesel and
>biodiesel? Will this still cause polution and global climate change? I
>would guess both burn hydrocarbons and therefore are much the same. Any
>chemists out there?
Yes, much lower on sulphur and particulates. Also destroys most types of
rubber hoses, check your fuel system before trying the stuff. Has CO2 but
it's not liberating CO2 stored in oil reserves, it's cycling rather than
>By the time you subtract the fuel it takes to grow the plant matter and to
>produce the fuel, is there any left over for other uses?
Not entirely sure, but keep a few things in mind; You are left with 45%
protein soy meal after extracting the oil, a common feed for animals. Most
soy in the US is roundup ready GMO that has an awfully low number of trips
for planting and harvest. Though there are clearly downside to GMOs this
particular crop is a net fuel saver over older methods.
>It seems most
>suppliers of any quantity may use petroleum based fuels to grow/produce the
>fuel, and therefore this could be a very inefficient way to feel good about
>one's own vehicle when in fact there is no real gain. It's kind of like
>running an electric car on electricity made from inefficiently burning
>coal; you may think you car is running clean, but you may in fact be
>causing more problems than you are solving.
Needs to be kept in mind. Ethanol has similar issues, but the byproduct
there is also a good feed and I understand it's a net + in energy production.
>If we find an easy, cheap and clean substitute to oil/gasoline, what
>incentive will there be to move away from an auto based society? There are
>many other problems with auto lifestyles than just the polution, climate
>change, and military infrastructure to protect oil interests and profits.
>Do we really want to make it easy for people to each have their own car?
>And what about the other 5 billion people that will want their cars?
People like cars, they are really handy machines. Realistically we need to
look at lowering the impact of auto ownership while pursuing rebuilding
rail and other mass transit systems.
>While biodiesel may be an interesting transitional phase, I don't see it as
>a long term solution to most of the problems we have now with cars and oil.
> The only advantage I can see is that it can be produced locally and on a
>dramatically shorter time frame. I come from a sustainability framework
>and want to avoid solutions that cause a half a dozen other problems. It
>seems that we need solutions that solve several problems at once, stacking
Ideally that's true, but we need to take the incremental improvents too;
these are not mutually exclusive.
Mark P. Ludwig
Poultry Research Lab
University of Wisconsin -Madison
More information about the permaculture