From pv magazine USA
Ethanol emits more greenhouse gasses than the gasoline it is supposed to replace. Additionally, ethanol (corn) farms greatly under-utilize land, which is one of the greatest resources in the United States.
Of the 92 million acres of corn planted in the United States every year, roughly 40 million acres (1.6% of the nation’s land) are primarily used to feed cars and raise the octane of gasoline. If this land is repurposed with solar power, it could provide around three and a half times the electricity needs of the United States, which is equivalent to nearly eight times the energy that would be needed to power all of the nation’s passenger vehicles were they electrified.
However, if the nation were to transition this 40 million acres of fuel to solar-plus-food (agrivoltaics), it could still meet 100% of its electricity needs, while also powering a nationwide fleet of electric vehicles.
Recent research by the Lawrence Berkeley National Laboratory suggests that utility-scale solar power in the United States generates between 394MWh and 447MWh per acre per year. Thus, just 1 acre of solar panels provides enough energy to propel America’s most popular electric vehicle – the Tesla Model Y – nearly 1.3 million miles per year.
In a good year, 1 acre of corn is expected to generate around 328 gallons of ethanol. Since ethanol contains only ⅔ the energy of gasoline, a comparable crossover SUV averaging 30 miles per gallon would travel only 6,600 miles per year on that acre of corn.
That’s not a typo – solar panels produce roughly 200 times more energy per acre than corn. This striking figure makes an ironclad case in favor of converting vehicles to electricity – and that’s before we take into account the environmental and health benefits which would result from the profound reduction in emissions.
The “recent” news that US ethanol emits 24% more emissions than gasoline, is in fact old news. Politics in the United States, influenced by agricultural industries, fossil-fueled fertilizer manufacturing, and perhaps a well-intentioned ulterior motive of underwriting food for national security, has led to a massive subsidy program for corn growers.
In fact, since 1980, pretty much all of the additional acres used to grow corn have gone towards fueling vehicles, not humans. We need not point fingers at farmers – they simply produce what the market demands. But these demands, which our civilization imposes on our soil, have resulted in far-reaching consequences.
Corn is particularly adept at siphoning nutrients from our soils. Restoring these nutrients requires fertilizers sourced from fossil-fuel feedstocks and produces more CO2 emission than any other human-driven chemical process on earth. Meanwhile, solar can help alleviate our nitrogen-fixation emissions crisis as well, by pulling fertilizer out of thin air.
With these factors in mind, we propose a new national security initiative – one that combines solar electricity generation with food production in order to solve many issues in one fell swoop. We urge landowners, developers, and legislators to prioritize the replacement of ethanol field corn with agrivoltaic operations. These operations should specifically target locations with the highest risk for fertilizer runoff. It’s time to bring our agrarian society into the 21st century.
And, just for the sake of fuel security, let’s incorporate some hydrogen generation into the picture as well.
About 40 million acres of ethanol field corn could be used to generate 14 petawatt-hours of solar electricity, if deployed in standard, highly efficient installation techniques. A reminder – that’s 3.5 times more energy than the current US electricity consumption.
However, that is not the goal. Even though the United States is still in the nascent stages of agrivoltaic development, it’s fair to say that solar-plus-food facilities will generate at least half the amount of electricity per acre as we leave space for farming machines. Analysis from Germany showed that potatoes could be grown at 80% of their initial volume, while electricity could also reach 80% of its potential.
In the scenario where we only get 50% of the solar output from the land, our repurposed acres would generate around 7 petawatt-hours of electricity per year. That’s eight times the amount of electricity required (~0.88 PWhrs/year) to push 3.26 trillion passenger car miles in the US every year, and enough left over to electrify the nation 1.5 times over.
Of course, we don’t need (or probably want just yet) to power the United States only via solar power. Thus we suggest powering the nation with only 50% solar – thus setting our electricity for our cars and our general power use around 16-21 million acres.
To continue reading, please visit our pv magazine USA website.
This content is protected by copyright and may not be reused. If you want to cooperate with us and would like to reuse some of our content, please contact: email@example.com.
The problem with batteries they will run out of raw material and are not user friendly in terms of charging and horrendous energy density and not easy to recycle. You will need to go to hybrid battery and hydrogen cars.
As I wrote before, and the author declined to publish, the net increase in corn acreage due to ethanol production is nowhere near the 40 million acres that go into ethanol. The byproduct of ethanol, distillers grains, are a high quality feed for cattle and hogs, and are now used in preference to whole corn. Other studies have concluded that the net increase of corn acres due to ethanol is about 8 million of those acres; the other 32 would be used to grow corn for feed now provided by the distillers grains. That does not negate the arguments against ethanol.
You’re wrong about batteries. They will become easy to recycle, just like lead-acid batteries, and grid batteries will be mostly iron for short-term and long-term storage. Hydrogen cars have no chance of catching on, for many reasons. Battery cars will easily take over by 2050, and nobody will look back.
The writer of this article is intellectually vacant as nuclear power is a much better solution and takes less land. What they also do not explain is the environmental damage done to our earth from rare earth metals required for both photovoltaics and battery technologies.
Solar panels don’t use rare earth elements Alex…neither do batteries.
Nuclear costs way more to build, and by the time anybody tries to build lots more nuke plants, batteries plus solar and wind, plus geothermal and green hydrogen burned in gas plants, will be cheaper and better than any new nuke plants. And you are wrong about rare-Earth elements, which are in all phones and computers, but not at all in the main batteries that will be used for cars and the grid. Solar also will ultimately not be as harmful as nuclear waste, by a long way.
When green is fully implemented the standard of living for every person on earth will rise dramatically
Solar waste can be recycled. Currently nuclear waste is dangerous for the next 24,000+ years.
By submitting this form you agree to pv magazine using your data for the purposes of publishing your comment.
Your personal data will only be disclosed or otherwise transmitted to third parties for the purposes of spam filtering or if this is necessary for technical maintenance of the website. Any other transfer to third parties will not take place unless this is justified on the basis of applicable data protection regulations or if pv magazine is legally obliged to do so.
You may revoke this consent at any time with effect for the future, in which case your personal data will be deleted immediately. Otherwise, your data will be deleted if pv magazine has processed your request or the purpose of data storage is fulfilled.
Further information on data privacy can be found in our Data Protection Policy.