Ethanol – Still a hung jury….

A perspective by Michael Carite, (Student in 425.601 – Principles of Energy Technologies – Fall 15)

 

Much of what we do as people is faulty. One way or another, we can jump into a new endeavor without truly understanding the full repercussions of our decisions. Many examples jump to our minds. Would cigarettes have ever become so popular in the middle of the 20th century if we had all of data on lung cancer and heart disease we do now? Would the original oil barons have burned off natural gas from their oil wells as a useless byproduct if they could see the booming industry today? So many atrocities, diseases, economic failures could have been avoided had we only known then what we know now.

Like cigarettes, as some issues progress, many try to ignore and block information from permeating to the public. We may potentially be witnessing this media blockade surrounding biofuels and ethanol. Ethanol is ethyl alcohol that can be created from plant biomass and used to replace common gasoline. Ethanol is commonly made from corn biomass due to its availability and sugar content in the alcohol creating process. Over the years, in an effort to eliminate the USA’s demand for foreign oil, the federal government has promoted the production and use of ethanol by subsidies and mandates.

The ethanol industry continues to grow, but have we realized the true repercussions of our decisions to promote this “green” fuel? Corn ethanol is created by taking the wasted biomass from corn harvesting and burning it in a cellulosic ethanol plant. Normally, this biomass is left in the fields, and some studies state that more carbon dioxide is emitted from the soil due to this removal and resulting in an increase in greenhouse gas emissions . Farmers will leave some of the harvesting waste in place to fertilize the soil, but generally remove about 11% of it for ethanol production .

Some argue that ethanol is negative net energy, meaning that it takes more energy to harvest, transport and manufacture ethanol than the ethanol created. It is true, even according to supporters of ethanol, that it takes more than 1 BTU of energy input to create 1 BTU of ethanol . The argument that follows is that a majority of the BTU input is biomass that would otherwise be wasted and not fossil fuels, as some claim. Fossil fuels are burned to create ethanol, but less than the ethanol output.
Other arguments against ethanol have risen over the years. Most notably, as outlined in a New York Times piece “The Biofuel Debate” by Tom Zeller Jr. , the indirect change of land use has become a hot topic. The argument states that as corn growing becomes more profitable, soy bean farmers in the USA will convert to corn, requiring more soy production from South America, namely Brazil. For Brazil to accommodate this production, they will have to cut down forest for more farmland. Effectively, to create ethanol with the hopes of reducing greenhouse gases in the world, we are eliminating the most effective carbon sink (the rain forest) to do so.
Is ethanol a positive fuel in terms of global warming? The verdict is definitely still out. We do know some things. Yes, CO2 is emitted from the ground as the biomass is removed for burning that would otherwise be captured, but is this validated through the net emissions benefits? Yes, ethanol production requires the use of fossil fuels, but ethanol supporters state the net emissions gain is positive. And yes, some soy producers are switching to a more profitable crop in corn, but can we truly measure and validate the indirect effects from land use change?

There are likely more questions than answers, and how we look at ethanol will change over time, much like cigarettes or natural gas. The question still stands. Is ethanol a net benefit to the environment?

 

[1] http://grist.org/news/corn-waste-based-ethanol-could-be-worse-for-the-climate-than-gasoline/

[1] http://www.scientificamerican.com/article/can-corn-ethanol-be-made-sustainable/

[1] http://americanenergyindependence.com/ethanol.aspx

[1] http://green.blogs.nytimes.com/2008/11/03/the-biofuel-debate-good-bad-or-too-soon-to-tell/?_r=2

 

 

 

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