Live data from Hacker News

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

reuters.com

91–100 of 264 posts

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

#91

Is there other crops that can be turned into ethanol that would be beneficial for the environment? Can't seem to find information on that.

Yes, including sugar beets, sorghum, and even cattails.

As far as whether we will or should use other crops, I doubt it. The whole thing with corn mostly came from the US having a large surplus of corn and needing something to do with it. Since we're operating on the false belief that the carbon cycle itself is a bad thing, and because we're trying to move to electric (theoretically), I don't think society is going to invest itself into more ethanol.

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

#92
I've seen a lot of these studies and the problem is always the same: the real-world spread on the inputs and outputs is always so much larger than what the report concludes. Since they're comparing ethanol and gasoline, you have two spreads to consider. As an example:

Worst-case for standard gasoline vs Best-case for corn ethanol:

A) Gasoline produced from Alberta tar sands syncrude (which has to be melted and partially hydrogenated using natural gas piped in from Northern Canada/Alaska) shipped by oil tanker (burning dirty bunker fuel) to California refineries for conversion to gasoline by distillation/cracking (with high CO2 emissions related to use of fuel to drive the require heating of the heavy crude oil);

B) Ethanol produced from corn grown with ammonia fertilizer made by splitting water with sun/wind energy, planted and harvested with renewable-powered electric equipment, and fermented and distilled into 95% pure ethanol (the eutectic limit of distillation) using only solar and wind power and in facilities right next to the farmer's fields;

And, conversely, the best case for gasoline and the worst case for ethanol:

C) Gasoline produced from regionally-produced light sweet crude with a minimal need for transport, hydrogenation or extensive processing, meaning much lower emissions from transportation and refining (we could even have electrolytic hydrogenation from water using sunlight to produce the hydrogen);

D) Corn produced in Kansas with large amounts of natural-gas-manufactured ammonia fertilizer, lots of natural-gas-derived synthetic pesticides and herbicides, planted and managed with diesel-powered equipment, then shipped overseas to China for fermentation and conversion to ethanol in a coal-fired ethanol distillery.

So if you break those spreads down you get a ridiculously wide range of estimates. Hence any specific number presented ('at least 25%' in this case) doesn't really tell you that much, other than if you dig through the specific methods used (which are generally hard to find, sometimes they'll put the methods in another paper hidden behind a paywall) you can tell what interest was backing this particular study. Some will even include things like the carbon emissions needed to feed the workers who grow the crops, or who work in the refinery, and so on, which is just nonsense. (The emissions of the restaurant workers who feed the oil refinery workers and the field hands have to be accounted for...?)

Personally, I think artificial photosynthesis is the vastly superior solution relative to either corn ethanol or crude oil gasoline, as you could plausibly run it anywhere with access to seawater and sunlight, saving agricultural land for food production (and conserving ever-scarcer potable water as well). It does however make sense to be able to convert excess agricultural production into useful products, although just composting it back into the soil might be wiser in the long run.

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

#94
post #69

Earlier quoted context omitted.

which is why the Democratic Party changed it under cover of starting with "a more diverse state" Iowa no longer first; Democrats reorder the presidential primary calendar for 2024 https://www.desmoinesregister.com/story/news/politics/2022/1...

> which is why the Democratic Party changed it under cover of starting with "a more diverse state" It wasn’t because they care about offending farmers or removing ethanol subsidies, it was so that Biden can lock down some early primary wins in 2024 with States with a higher percentage of black voters.

If absolute fairness were the reason for change ALL parties that primary would do so by some algorithm that's transparent.

E.G. 5 Primary waves (Tuesdays/weeks/months) sorted by the 10 states with the least population to the most population.

Why? It's a better rough approximation for a representative sample over an increasingly large window of voters than the current process, and still keeps any benefit of ramping up from smaller to larger populations to narrow overall selection in the field. Plus the algorithm is so simple that it can be outlined in a sentence.

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

#95
post #69

Earlier quoted context omitted.

which is why the Democratic Party changed it under cover of starting with "a more diverse state" Iowa no longer first; Democrats reorder the presidential primary calendar for 2024 https://www.desmoinesregister.com/story/news/politics/2022/1...

> which is why the Democratic Party changed it under cover of starting with "a more diverse state" It wasn’t because they care about offending farmers or removing ethanol subsidies, it was so that Biden can lock down some early primary wins in 2024 with States with a higher percentage of black voters.

Nah.

It was payback to Jim Clyburn for the stunt he pulled in 2020 re: Bernie.

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

#96
post #29
post #19

Earlier quoted context omitted.

The ethanol is required as an anti-knock additive. The past alternative was tetraethyllead, which had catastrophic environmental impact. https://en.wikipedia.org/wiki/Tetraethyllead#Antiknock_agent

I find ethanol actually increases knocking in all of my engines. Switched to ethanol free years ago and I recall it made a difference in performance and mileage.

It will take time for the computer in the car to detect the ethanol and switch to a high ethanol fuel map. In the mean time, the engine is going to run pretty lean, since more ethanol is required than gasoline for the same volume of air. Running too lean usually causes the engine to buck and shake pretty badly.

This, of course, assumes that the car is even capable of running higher ethanol blends.

The performance benefits are mostly from turbocharged engines. Though, Chevy V8s can see solid torque gains over 4000 RPMs.

Once you get into the E50+ blends, you should have seen a huge mileage reduction. 10-20% for E50 and 25+% on E85. There's so much less energy density in ethanol.

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

#98
post #65
post #32

Earlier quoted context omitted.

On a first approximation, food production (including corn) is just channeling natural gas into fertilizers through Haber–Bosch. If the produced food isn't actually being eaten, it's just a highly inefficient energy conversion Rube Goldberg machine. Now to answer your question, food production unlocks plenty of carbon underground through natural gas.

Not to mention all of the fuel used to move around the fertilizer, tractors, finished corn, the energy used to grid/heat/ferment/distill into ethanol, and then to truck around the ethanol. It's actually almost hilariously indirect and inefficient when you think about it.

Well all the final products (contextually, material fuels or just energy) have a production history: to call one of them inefficient you need to compare production processes. Diesel fuel does not come ready from "diesel springs".

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

#99

Earlier quoted context omitted.

Octane on its own is an anti-knock additive. And ethanol actually makes your mileage go down because it is less energy dense.

How can adding octane be an anti-knock additive? Isn't the rating normalized too octane, so it can't bring the average under 100, ever? Like, compared to even worse carbon chains than octane? Edit: Never mind got the scale backwards. I'll keep the comment here to shame myself.

Octane is a measure of the relatives ratios of the octane molecule with some other (I can never remember which). 100 octane means the fuel acts in your engine the same as fuel made from 100% octane molecule. 0 octane means it acts like 100% the other, 90 octane mean it acts like a mix of 90% octane and 10% the other.

You can go below 0 or above 100 if you find some other molecule/mix that acts worse/better, though how you extrapolate beyond the 0-100 range is subject to debate, confusion and deception. Ethanol is clearly better than pure octane, though how much depends on how you choose to extend the scale.

Post reply on HN