Environmental Engineering Reference
In-Depth Information
because it allowed them to sell more corn; ethanol produ-
cers liked it because they could sell more biofuels and
make more money, and the environmental groups liked
it because it put a requirement on new plants that would
reduce emissions. This was supposed to be a win for all
sectors over what was required by the
law that only
mandated
and had
no requirement on life-cycle greenhouse gas emissions.
There is another problem that only politicians could
have created. The amount of ethanol is a requirement,
and gasoline blenders that do not blend the required
.
billion gallons of ethanol in
%
into all they produce are subject to a
fine. Unfortunately,
there is not enough ethanol produced to meet the require-
ment, and the fuel makers, not unreasonably, say if we can
'
t
get it we should not have to pay a
fine. It is an interesting
dilemma and I wait to see how it plays out. Just because the
fuel makers are right does not mean they will win.
There are, of course, cautions; we do not want to get
into a regime as bad as corn ethanol with all of its dele-
terious effects on food prices and land use. The hope for
the cellulosic program is that crops can be grown on land
that is only marginally useful for agriculture. The focus is
on fuel crops that are perennials like grasses and forest
waste rather than annuals like corn. Perennials sequester
CO
underground in their ever growing root system.
Converting a
field from a perennial to an annual crop
increases emissions as the carbon trapped underground is
slowly released. It takes many years to get it all out and in
that period even cellulosic ethanol will have larger green-
house gas emissions than gasoline. A recent study of the
effect of land-use change illustrates the problem [
].
For example, converting land to corn for ethanol
