
Corn ethanol plant – image from Google Earth
Let the pandering begin. Since this is the summer before the totally useless and unrepresentative Iowa caucuses, we get to see politicians from both parties extolling the benefits of using corn-based ethanol in gasoline. Since we gained a legislative mandate to use ethanol beginning back in the 1970’s when it was pitched as a way of growing our own energy, this mandate has become the truly untouchable political position, even though it causes much more harm than good.
Ethanol from corn has been pitched as a way for the US to become less dependent upon foreign sources of petroleum. It still is argued that it is good for the US, since almost all studies show a net positive gain in energy production. But let’s look at corn ethanol in more detail. The studies that are available date back to the early days of this century. They show corn ethanol to be slightly positive in terms of energy made available per unit of energy input. For corn, this would include fertilizer energy, tractor diesel fuel, and energy used in extracting corn sugars which are made into ethanol. Here is a chart that shows the energy balance for most of the common sources of energy:

As can be seen, biofuels are on the far right hand side of this chart. Data from industry sources indicate that the energy balance has increased to 3-4 times as much energy produced compared to input energy for many facilities. This is to be expected as the corn ethanol industry becomes mature and has incremental improvements. But let me say that even at the high point of industry surveys, corn ethanol is a poor source of pure energy. A lot of inputs must go into ethanol from corn in order to gain the available energy.
First, please note that about 60% of Iowa’s corn goes into ethanol production. That means that the Iowa farmer, popularized by Grant Wood in his American Gothic painting, must continue to grow corn at a high rate in order to satisfy industries need to comply with the ethanol legislation. That legislation calls for 36 billion gallons of bio-based ethanol to be produced and blended with virgin gasoline. So what are the non-energy impacts of this amount of corn production? It would seem that this corn production is a significant contributor to the dead zone in the Gulf of Mexico as excess nutrients and soil flow down the Mississippi River to mingle with the Gulf waters. This dead zone keeps increasing in size, and by 2021 totaled over 6,000 square miles where the excess nutrients enabled blooms of algae. These blooms deplete the oxygen in the water, creating this dead zone where no other marine life can exist. All because what began as an effort to replace imported oil, has become an essential backstop for the farm economy. And nowhere is that more clear than in Iowa.
So politicians all pay homage to what is now the status quo, where overproduction of corn to satisfy legislated mandates are sacred. Since Iowa still maintains an outsize influence on the political discourse of the nation, no one who wishes to grab the brass ring of the US Presidency dares to question the advisability of using US corn to create a gasoline extender. We will see homage paid to the hard working farmer, and the discussion will be framed so that every gallon of ethanol produced displaces a gallon of oil imported from our enemies. Who could be against that?
Oh, wait a second. What happens with the electrification of the transportation sector? If more and more vehicles are electric, will politicians adjust the requirements downward to reflect lower gasoline production? Yeah, what planet do you reside upon? You expect politicians to reflect reality in their expounding? Or do you expect a continuation of what is now a well-established status quo, with political influence overcoming reality?
I will be watching the discussion this summer as the politicians pledge their fealty to maintain this ethanol mandate. If any politician dares to address the issue, and call for reduced ethanol production, I would be amazed (and would consider that politician for my vote). But I do not expect anyone to make a politically unpopular proposal in the most agricultural of all states, Iowa.
Before I leave the topic, there is one good thing ethanol blending has caused. Since ethanol is a good solvent for water, the issue of gas line freezing in winter has vanished. If you do not have a separate water phase, you will never freeze the lines, and this has reduced the advantages certain gasolines had in preventing gas line freezing.