Ethanol Mandate for Iowa?

Gig 601XL Builder wrote:

The problem is if you use a gallon of Ethanol to produce 0.99 gallons of
Ethanol all of the fuel produced will go into production and you are going
to have to add .01 petro just to break even.

then could it still have a practical use as a means of storing
energy instead? I mean, producing ethanol using the output of
say nuclear plants (ok, replace that with wind mills or whatever
takes your fancy if 'nuclear' is against your religion); it was
my (probably mistaken) understanding that the output of a nuclear
plant could not easily be throttled up or down...

any recommendation about some good reading on the subject of
alternative fuel technologies?

--Sylvain