Grass makes better ethanol than corn does (2008)

[myshpa]

Corn-Based Ethanol May Be Worse For the Climate Than Gasoline, a New Study Finds (2022)

Long touted as a renewable fuel emitting 20 percent fewer greenhouse gasses than gasoline, ethanols’ emissions may be 24 percent higher.

https://insideclimatenews.org/news/16022022/corn-ethanol-gas...

https://www.pnas.org/doi/full/10.1073/pnas.2101084119

[neltnerb]

Yeah, and the sad thing this is definitely not news.

https://link.springer.com/article/10.1007/s11053-005-4679-8

Don't even need the article, the abstract says exactly the same as this result from 17 years later. What are we doing...?

Ethanol Production Using Corn, Switchgrass, and Wood; Biodiesel Production Using Soybean and Sunflower, March 2005

"Ethanol production using corn grain required 29% more fossil energy than the ethanol fuel produced."

The only difference is that now switchgrass, which was known 17 years ago to have this advantage over corn if cellulosic ethanol is working, has this advantage over corn now that cellulosic ethanol is working...

If you make cellulosic corn ethanol, by the way, that 29% doesn't apply either. It's an apples and oranges to compare sugar based corn ethanol to cellulosic based switchgrass ethanol.

[credit_guy]

In reality ethanol is not used as a renewable fuel, although it is touted as such. It is simply used to increase the octane rating of gasoline. Without ethanol we'd need lead. Or some stuff that would be worse. Or, we'd put up with the lower octane rating, and so less efficient engines, and fewer mpg, and more CO2 emissions.

[dmbche]

"In the new study, Lark and his colleagues found that after the RFS took effect, farmers expanded corn production on nearly 7 million acres each year, causing the conversion of lands to cropland “such that the carbon intensity of corn ethanol produced under the RFS is no less than gasoline and likely at least 24% higher.” The policy, the study said, also resulted in increased fertilizer use, water pollution and habitat loss."

[raverbashing]

Here's the secret: don't make it from corn.

At least not until you manage to convert the whole plant to Ethanol, stalk and all

(I mean it's not a secret, more than the US being overly invested on corn)

[wodenokoto]

But doesn't the corn fields suck that back up?

[unglaublich]

Stop using fertile land to produce fuels for energy hungry cars and energy for industry. Use fertile land for FOOD.

Then, use all the rest of the land for energy production: roofs, parking lots, infertile land.

[throw3823423]

If your goal is maximizing acreage for farming, a pretty good idea would be to get rid of land dedicated to our number one crop: grass that gets mowed. We spend over 40 millions of acres in lawns, as farms get replaced with subdivisions that are well over 50% lawn, and most of the rest is asphalt.

Your typical American metro area is very low density, but not because it has a lot of land dedicated to farming, or old growth woods, but because we dedicate so much space to very low density development that erases whatever was in that land in the first place. The trees are not local, the plants aren't local, and neither is the concrete.

[irjustin]

Question, don't we have enough food production[0]? Basic search says we're doing well enough in that regard.

[0] https://news.thin-ink.net/p/we-produce-enough-food-to-feed-1....

[cubefox]

Nuclear power plants use of land is almost zero compared to wind farms and solar parks.

[dmbche]

This video is an interesting look at this whole issue:(Engineering Explained - America Was Wrong About Ethanol) https://www.youtube.com/watch?v=F-yDKeya4SU

Especially his summary, where corn creates 20 percent less GHG than gasoline and ''breaks even'' after 28 years, while switchgrass creates 94% less GHG and breaks even in it's first year.

[soperj]

It was never about GHGs, always about subsidizing corn farmers.

[jvanderbot]

Switchgrass farmers don't vote enough. The whole ethanol thing was just to prop up corn prices and production during election runs.

[hawk_]

Thanks for that summary, the video doesn't say much more other than repeat these things over and over.

One thing that wasn't clear is why does tilling the land release so much carbon into the atmosphere?

[hannob]

If you want something that is more up-to-date and covers this topic, here's a good podcast: https://www.volts.wtf/p/whats-going-on-with-biofuels

Most important fact: All these promised second generation biofuels technologies, from which switchgrass was one, didn't happen.

[red-iron-pine]

why didn't they happen? im not in a place to listen to a podcast

[thegridre]

Switchgrass is a natural solar panel that converts sunlight into chemical energy. It has many benefits, like improving soil quality, storing carbon, and reducing emissions. It can also be burned with coal in existing plants, which is convenient. Switchgrass is a promising biofuel that can help us transition away from fossil fuels. It has a lot of potential to grow in various conditions and produce high yields with low inputs. It also has a positive environmental impact by sequestering carbon and reducing greenhouse gases. Switchgrass is not without its challenges, but they are not insurmountable. It needs more research and development to make it more efficient and cost-effective. It also needs more support from farmers, scientists, and policymakers who are working to make it a viable option. I think switchgrass is a great idea, and I’m excited to see how it evolves in the future.

[rdevsrex]

Who didn't already get that ethanol was about corn subsidies and not the environment?

[hammock]

Probably a lot of people the same way many don't get what so many other climate change initiatives are about

[bluGill]

Corn is a type of grass. So is sugarcane. (The article is about switchgrass, not generic grass)

I know attempts have been made to use more than just the corn seed into ethanol. The big disadvantage is that you take away a lot of nutrients from the soil forever. Sulphur for example doesn't go back, and so the more of the plant you take away, the more you have to add back as fertilizer .

[sidewndr46]

If only there were at thick black viscous substance rich in sulfur that was present in the Earth's crust we could harvest easily, then extract the sulfur, & then use to create fertilizer.

[legulere]

I don’t know switchgrass, but with miscanthus another perennial grass, at some point the nutrients mostly get taken back to the roots and what you harvest has a very low mineral content.

[pstuart]

seems like the waste from digesters could be returned back as fertilizer.

[photochemsyn]

Just take the CO2 from the atmosphere, concentrate it to a 100% pure CO2 stream, then generate a 100% H2 stream from water, blow off one O to make CO (carbon monoxide), now we're into well-characterized Fisher-Tropsch and Sabattier processes...

https://en.wikipedia.org/wiki/Fischer%E2%80%93Tropsch_proces...

https://en.wikipedia.org/wiki/Sabatier_reaction

Why on earth would you devote a scrap of quality agricultural land to ethanol production? You might as well just compost lost crops, get better production later. Seriously, biofuels are like raising seals in pens so you can kill them and get lamp oil from their blubber, it's just stupid.

[jabl]

Yes. Another variation on this scheme (which AFAIK the Porsche synthetic fuel plant in Chile is doing) is producing methane from atmospheric CO2 and H2 from electrolysis, then converting methane to methanol (how most methanol is produced today, albeit from fossil methane (natural gas)), and finally converting methanol to gasoline with the methanol-to-gasoline (MTG) process.

But in the context of corn ethanol in the USA, none of this has anything to do with the environment or sane economics, it's all just an agricultural subsidy scheme.

[jonnycomputer]

Switchgrass farming would be no-till farming, and on net would probably increase (and stabilize) the carbon content locked in soils. Another respect in which it would be much better than corn for ethanol.

The exact effect appears to depend on soil quality, e.g. https://www.nature.com/articles/s41396-021-00916-y

[rrlevy]

I still find it crazy that we are capturing solar energy on plants, growing them, and then burning them to get energy to move our cars…

It seems so much more intuitive to just capture solar to electricity and use an electric car…

[vondur]

It's indirectly solar power, and ethanol can hold more energy per volume than batteries. However all of the other inputs that go into growing ethanol cancel that advantage out. If we were using Nuclear or maybe pure solar to produce the fertilizer perhaps the math may work out.

[olliej]

The energy density of fuel is much much higher than electricity, which makes using fuel to transport energy to where it is needed is much easier, and it makes the effective range for gas much higher because in those cases where you need it you can always just take extra gas (even taking into account the relative engine efficiency, to the worst possible degree gas is more than 10x the miles per kg than current battery tech).

Add to that speed of refueling vs. recharging, the many areas where power is not available at all, let alone super chargers (absent specialized charging hardware charging an EV takes days), etc fuel still has real value.

There are vast swathes of the world where grid power is not available, so the only available power is via diesel generators, which are generally around 40% efficient. At that point using an EV is not only slower, but at that point the best case efficiency (watts/kg) is less than 34% vs a diesel car engine's 43% energy efficiency.

If you have the right environment you might be able to use solar to charge the car, but I think for that you need something like 6kW of solar panels per car you want to use each day, and an additional car worth of batteries to store power during the day because you're presumably using your car at during the day. That's not a trivially portable system, so still doesn't fix the "I am driving a long distance where there aren't super chargers".

[coderenegade]

Depends on the use case. I live semi rurally and an EV would be a tough sell for most people here. I do see a few of them, but these are households with multiple vehicles where the EV is a runabout, and work is done using diesel or petrol, often a 4x4 from the 80s or 90s with the better part of a million kms on the body.

[rrlevy]

BTW, I live in Brazil where ethanol from sugarcane is widespread

[dmbche]

It's a lot less work per Kwh to harvest the energy that plants store than what would be needed to make and maintain solar panels to make the same amount - I assume

[anon291]

Well we can store corn and oil and can't really store electricity.

[mewse-hn]

  "It's a prediction because right now there are no biorefineries built that handle cellulosic material" like that which switchgrass provides

so.. nobody can ferment it but it gives a higher ethanol yield than corn.. how does that work

[phtrivier]

The article is from 2008. What happened in the 15 next years on this front ? Is any biofuel actually produced this way ? How many cars can use it ?

Or is the submission a troll on modeling ?

[toomuchtodo]

https://www.eia.gov/energyexplained/biofuels/ethanol-supply....

https://www.eia.gov/tools/faqs/faq.php?id=27&t=4

https://www.eia.gov/tools/faqs/faq.php?id=90&t=4

https://apnews.com/article/ethanol-e15-gasoline-midwest-epa-...

Coincidently, increasing EV sales threatens ethanol production, so there are calls for increasing ethanol in fuels to compensate. Subsidies typically don't die quietly, unfortunately.

[sidewndr46]

Well, this happened for one: https://www.clarionledger.com/story/news/politics/2017/07/30...

[seltzered_]

Algal biofuel boom-bust of the early 2010's: https://www.greentechmedia.com/articles/read/lessons-from-th...

[bumby]

Isn't part of the idea that corn makes more sense to subsidize because it multi-use? I.e., it can be food and fuel?

>"This is an energy crop that can be grown on marginal land,"

This seems like the lede and comparison to corn is missing point and opening itself up to counterpoints that detract from the value of using grass on land that would otherwise probably only be used for grazing.

[dragontamer]

The land-conversion from forest or grassland into farmland is a surprisingly large effect on the environment.

Making Ethanol from natural grasses and keeping the land natural is one of the best things we can do for the environment, as well as creating an alternative means of capturing solar energy.

You know... if we can get it to be commercially successful. If we can't sell the darn thing, then it'd never happen. But the theory is sound and enough prototypes have been created that we know how this works.

[eyelidlessness]

I’m having a pedantically tough time with this headline. It’s like saying “pork makes better lard than ham”, or “grain makes better whiskey than rye”. Maybe that’s true, the superset might have better properties for the purpose than the subset? But it’s a really strange distinction to make.

[baseline-shift]

That article was 15 years ago, back in 2008. If it was a better alternative, we'd have seen it by now.

[nazgulsenpai]

Yes but corn makes better campaign donations than grass does.

[Gordonjcp]

Meanwhile as part of the process of making plastics, we're flaring off enough propane and butane to run millions of cars.

[aaronbrethorst]

Corn-based Ethanol is used to curry favor with Iowans who hold (for Republicans) the first in the nation presidential primary contest (actually a caucus, but it’s the first voting event on the primary calendar).

It was also the first in the nation voting event for Democrats until the IA Democratic Party thoroughly botched the 2020 caucuses.

[anon291]

Corn is a grass so without saying which species of grass do this, the title is useless.

[pkphilip]

Would this work with regular lawn grass? if so, you could think of having huge amount of this raw material for ethanol production worldwide.