Corn on the cob or fuel in your tank

Biden administration discusses boosting ethanol production to lower gas prices

‍As inflation soars, Biden turns to ethanol to lower gas prices (nbcnews.com)

This Week’s Reason for Hope

E.U. taking steps to phase out cars that run on fossil fuels

Environment committee voted to support having 2035 as last year fossil fuel cars can be sold

E.U. has target to become net zero by 2050

Assumption – a car is on road for 10-15 years

E.U. parliament to vote on climate proposals in coming months

Norway, while not an E.U. member, is already on the path to zero internal combustion vehicles by 2035

Electric vehicles sales hit 84% of all new car sales in January

Sources

EU lawmakers back effective ban on new fossil-fuel cars from 2035 | Reuters

Norway: BEV Share Hits Record, PHEVs Collapse In January 2022 (insideevs.com)

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Intro

Biofuels are made from plant feedstocks - corn, sugarcane, palm oil

Ethanol is run in gasoline engines

• E10 blend – most gasoline sold in the U.S. 
• E85 blend – can only be used in flex fuel vehicles

Biodiesel is run in diesel engines - more prevalent in Europe

Criticisms of corn-based ethanol

Land Intensive - deforestation and displacement of food production

U.S. 

• Corn production (2010 onwards) - roughly 80 million acres
• About 40% used for ethanol or 9% of total US arable land
• Big expansion of corn ethanol led to - double cropping and pulling land out of conservation

Globally 

• Growing feedstock crops for ethanol (as well as biodiesel) has led to deforestation as existing crops / ranching is displaced

Limited positive to net negative greenhouse gas (GHG) impact

USDA study – corn ethanol produces 39% lower GHG emissions than gasoline

Study released in earlier this year – corn ethanol produces 24% higher GHG emissions than gasoline

• Differences in results attributed to how land impacts were assessed
• Increase in corn acreage led to ground being taken out of conservation programs
• Tilling land to grow crops releases carbon into the atmosphere

Air quality impacts

E10 blend ethanol 

• Does reduce some tailpipe emissions
• However, makes fuel more likely to evaporate leading to more smog

E85 blend ethanol - 2007 study modeled impact on air quality and found net result was actually worse than standard gasoline

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Solutions to corn ethanol downsides

Use waste ground to grow feedstock rather than prime cropland

Fertilize less

Power ethanol production facilities on renewable energy

Move to cellulosic ethanol

• Uses both stalks and husks of corn (not just grain)
• Can be made from crops and plant residues - switchgrass, woody debris, straw

Fuel efficiency example

2009 study – looked at how many miles a car could travel based on one acre of switchgrass

Conventional gas SUV

• Fuel - cellulosic ethanol produced from switchgrass
• Miles traveled ~ 9,000 highway miles

Electric SUV

• Fuel - electricity produced from burning switchgrass (bio energy)
• Miles traveled ~14,000 highway miles

Additional benefit of option 2 - carbon from bioenergy can be captured while carbon emissions from car tailpipe cannot

Sources

https://www.ers.usda.gov/topics/crops/corn-and-other-feedgrains/feedgrains-sector-at-a-glance/

Is Ethanol from Corn Bad for the Climate? - Scientific American

Building the Evidence on Corn Ethanol’s Greenhouse Gas Profile | USDA

U.S. corn-based ethanol worse for the climate than gasoline, study finds | Reuters 

Livecycle Greenhouse Gas Emissions for Select Pathways (July 2016) (epa.gov)

Carbon-Negative Biofuels from Low-Input High-Diversity Grassland Biomass (science.org)

Cellulosic Ethanol - an overview | ScienceDirect Topics

Understanding The Debate Over Ethanol And Smog (forbes.com)

Ethanol A Significant Risk To Human Health, Study Finds | Science 2.0 (science20.com)

Biomass To Electricity Is Better Energy Than Ethanol | Science 2.0 (science20.com)

A push for low-carbon fuels pays off in California (science.org)

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