[Gasification] Cellulosic Ethanol a dead end

[Bill Klein]

... Finally, if that wasted energy is coming from biomass it is still wasted, but it is 100% green.

This term "green" not only gives me a problem, but seems to be at the base of many of today's difficulties, even giving birth to fanaticism. For example, where does one decide the line between "green" and whatever its opposite is gets drawn. Certainly, except for the fundamentalists, the line is arbitrary and often moved. 

Having made that statement, biomass may be whatever color one wishes to prescribe, but a great deal of coal and petroleum must be consumed before the first chip can enter the hopper and, I imagine, if the application is dual fueling, then it is a "black balled" project? For that matter, a great deal of coal and oil are consumed before one sees the first chip.  

Please can we move away from trying to convert a carbohydrate like cellulose into a liquid and start discussing the means by which we convert it into a gaseous compound? Granted, it's not a green gas, but what's the problem with a clear clean gas anyway? Let's talk about gasifiers, gasification and gasification systems, while every now and then kick around some ideas about feedstock preparation and delivery systems.   

Thank you. 

Bill Klein  

         




----- Original Message ----- 
From: "Pels, J.R. (Jan)" <pels at ecn.nl>
To: "Discussion of biomass pyrolysis and gasification" <gasification at listserv.repp.org>
Sent: Monday, November 12, 2007 10:44 AM
Subject: Re: [Gasification] Cellulosic Ethanol a dead end


This 35% result is of course terribly low. It means that for every
gallon EtOH you need two times the energy in that gallon to produce it. 

> If you think converting the 70% starch in corn into sugar and 
> then into ethanol is inefficient, (MAYBE 35% more energy out 
> than in) 

But you have to get your references correct. Is it gasoline from oil?
Well, you don't get 100% gasoline from oil. You waste some of it in the
refinery. (Hard to get a number, since a significant part of the oil is
converted to other useful products).

Let's not forget that alternatives to oil also waste. E.g., tar sands
need 0.6 barrel of oil extra to produce 1 barrel of oil. And then some
is lost when it is processed into gasoline. Fisher-Tropsch diesel from
coal is equally wasteful.

And also, if the lost energy is useful heat it is not wasted. This
applies to all examples.

Finally, if that wasted energy is coming from biomass it is still
wasted, but it is 100% green.

Jan

========================================
Dr. Jan R. Pels
ECN - Biomass, Coals and Environmental Research
P.O. Box 1, 1755 ZG Petten, The Netherlands
telephone: +31-224-564884; fax: +31-224-568487
mobile: +31-6-10923218
e-mail: pels at ecn.nl
========================================
 


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