Biofuels Could Reduce Greenhouse Gas Emissions By 96%

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There is nothing inherently wrong with internal combustion engines. The problem is the fuels we use to run them emit billions of tons of greenhouse gases every year, gases which cause the Earth to get hotter. The byproducts from burning gasoline or diesel fuel account for almost a third of all US greenhouse gas emissions according to the EPA.

It’s true that internal combustion engines are less efficient than electric motors. In a perfect world, we would take the billions of them in use in the world today and replace them with motors powered by  sunlight or wind or ocean waves. And someday we will, but it will take many generations to make that happen. What do we do in the meantime?

Biofuels Breakthrough

A new report published by the National Academy of Sciences is based on a joint research project by the Argonne National Laboratory, the National Renewable Energy Laboratory, and Oak Ridge National Laboratory. It offers a cost effective way to make biofuels that can be directly substituted for gasoline, diesel fuel, or jet fuel with few if any changes to the engines. Depending on the source of those biofuels, greenhouse gas emissions would be reduced from as little as 40% all the way up to 96%.

Just think for a minute what slashing exhaust emissions by 96% might mean. The world is on a trajectory that will see renewable energy replace fossil fuels eventually. But there may not be time enough for the transition to be completed before an existential crisis for most living things on Earth occurs.

What if while we are waiting for renewables to become the norm we eliminated the vast majority of tailpipe emissions? The only people who could possibly object are fossil fuel companies, but why should they be allowed to continue poisoning the environment just so their stock prices don’t plummet? What if instead of spending trillions of dollars on carbon capture or geo-engineering, we simply burned something else instead?

A One-Step Process

We know we can make ethanol from plants. But converting it to a hydrocarbon fuel that conventional internal combustion engines can use is a complicated, three-step process that adds significantly to the cost of the fuel. Using the latest advances in catalysis and process development, researchers have created a conversion process that combines all three steps and lowers costs significantly.

The one-step process is known as Consolidated Alcohol Dehydration and Oligomerization, or CADO. But what does it mean for emissions? To find out, the researchers enlisted the aid of scientists at the Argonne National Laboratory. They have created a computer analysis tool known at GREET, which stands for Greenhouse Gases, Regulated Emissions, and Energy use in Transportation.

The program simulates energy use and environmental outputs of various vehicle and fuel systems and has been used 40,000 times by researchers around the world. It can analyze multiple vehicle and/or fuel systems, taking into account where raw materials are mined or extracted to when they are disposed of or emitted. It is a well to wheel analysis which calculates the energy use and emission levels throughout.

“GREET is one of the only tools out there that can provide a complete picture of the energy and environmental impacts of an entire vehicle and fuel system,” said Michael Wang, the leader of the GREET team at Argonne, and one of the co-authors of the study.

Lifecycle GHG Analysis

Argonne researchers used GREET to calculate the life cycle greenhouse gas emissions produced by hydrocarbon fuels made from different raw materials and conversion methods. Some of the raw materials analyzed were corn and sugarcane as well as sugarcane straw and corn stover. The difference is the using the first group takes food out of the mouths of people and animals while the items in the second group are often considered waste products to be discarded.

“Variations in the feedstock used to make ethanol and pathways used to convert it, yield different levels of GHG emissions,” said Argonne energy systems analyst Pahola Thathiana Benavides, another co-author. The analysis showed that hydrocarbon blends made using the CADO conversion process reduced greenhouse gas emissions anywhere from between 40% up to 96% depending on the feedstock and the conversion pathway. GHG emissions fell by 40% with corn grain, 70% with sugar cane juice and 70-96% with cellulosic biomass such as sugar cane straw and corn stover.

Cuanto Cuesta?

So how much would all this cost? The graph above shows costs today in the lab. The researchers project that within 2 years, the cost at commercial scale would be less than $2.00 per gigajoule. According to Fortis BC, a gigajoule is equivalent to 26 liters of gasoline or 277 kilowatt-hours of electricity, which puts the cost of the process at around 30 cents a gallon.

That does not include the cost of ethanol, which according to Biofuels Digest is about $1.22 a gallon. Most ethanol in the US today comes from corn, a principal food staple. It’s not hard to imagine that ethanol from less valuable feedstocks like sugar cane straw or corn stover would cost less. So the total cost of biofuels using this process should be about $1.50 per gallon. Double that to include transportation and storage and the price at the pump should be right around $3.00 per gallon.

Would people be willing to pay 3 bucks a gallon for a fuel that requires no modification to their existing vehicle but slashes exhaust emissions by up to 96%? You would like to think so. Some will carp that fuel economy will be less on ethanol than on gasoline. OK. If that is a concern, then let’s say the effective cost of ethanol versus gasoline is $4.00 a gallon.

Would you rather pay a dollar more a gallon or would you rather your grandchildren die an untimely death on an overheated planet that will drift lifelessly through space for millions of years before it regenerates itself? That should be an easy question to answer but in today’s world where everyone is captivated by things that won’t amount to a pisshole in the snow in the long term, the answer may not be so clear cut.

An Exciting Future

“In order to move towards more sustainable development, we will need fuels that can generate fewer emissions and that are economically feasible,” Benavides said. “This work is an exciting indicator that building such a future is possible.”

Exciting may be too mild a word. This research could be exactly what the world needs to reduce greenhouse gas emissions dramatically in the near term. No new pipelines, storage tanks, or pumps needed. No expensive conversions of existing engines. Refueling would take exactly the same time as it does the tank with gasoline or diesel.

How will people and governments react to this news, which could turn trillions of dollars worth of extraction and refining equipment into worthless junk overnight and decimate the value of energy companies? We will know soon enough. If you hear about this in the mainstream press anytime soon, that will be one thing. If you don’t, that means the fix is in and the fossil fuel companies have been busy burying this news under a mountain of fear, uncertainty, and doubt. And buying politicians to keep the gravy train going for those companies.

Not every discovery in the lab results in commercially viable solutions, of course. Whether this research ever makes it into the mainstream of commerce, no one can predict. But compared to the time and energy that will be consumed trying to geo-engineer the atmosphere or capture carbon dioxide from the atmosphere and bury deep beneath the oceans — both of which will cost trillions of dollars — investing in further exploration of the CADO process seems like a no-brainer.