OK, thanks - that’s really quick work on your part.
Growing season - it varies widely. A “90 day corn” is on the shorter end of some corn varieties, 110 day is on the longer end, but 90 is a workable starting point. The longer we make the growing season, the greater your numbers, of course.
The by-product of DDG’s needs to be taken into account here in two ways - there’s a whole lot of energy used in drying those distillers’ grains (which, if we could assume a feedlot very close to the ethanol plant, we would not need), and the feed value of the DDG’s is giving us a huge win as feed. We’d either be using cracked corn for feed, or DDG’s. Either way, we’re going to grow corn - so IMO, getting ethanol *and* feed from the same acres, same crop and same growing season means we’re getting a win here.
Unless America is going to become a nation of tofu-nibblers, the feedlots are going to be cramming *some* sort of feed into those cattle to finish them. We can either use cracked corn and get no ethanol, or distillers’ grains and get the ethanol. The big point I have to keep driving home to people is that the majority of both corn and beans (soybeans to non-farmers) grown in the US go into cattle feed, so when we have a viable after-product from biofuels that still feeds cattle, we really need to take that use into account, because we’d be using the diesel/etc to produce feed that has no fuel component removed anyway.
about DDGs
value of DDG is about 25% that of the corn it started out as.
IMO, correct corn-input , by multiplying
input by 0.75, to correct for value of the co-product.