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Big agriculture mislead the public about the benefits of biofuels

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Re: Big agriculture mislead the public about the benefits of biofuels

#131

Post by jkhdigital »

jbstack wrote: post #115
scaramanga wrote: post #80

Earlier quoted context omitted.

It's explained in the article. People aren't going to starve to fill their gas tank so you need to grow more corn to offset that used for biofuel. To do that can require destroying other carbon sinks (wetlands are the example given, sometimes dried and then burned) to turn them into fields. But in any case, carbon from the ground is used to fertilize the fields to grow the corn. For every unit of energy produced by c…

"People aren't going to starve to fill their gas tank so you need to grow more corn to offset that used for biofuel. To do that can require destroying other carbon sinks (wetlands are the example given, sometimes dried and then burned) to turn them into fields" This doesn't make any sense to me. With petrol, you are transferring carbon from a store to the atmosphere every time you use it for energy. With a wetland, y…

Except that industrial-scale agriculture in general requires quite a bit of exogenous petrochemical inputs—not just the fuel to power the machines that do the work, but also the fertilizer.

Re: Big agriculture mislead the public about the benefits of biofuels

#132

Post by sl-1 »

eptcyka wrote: post #48
knappe wrote: post #45

Earlier quoted context omitted.

That it isn't sustainable. As Eating the Earth points out, by growing trees to then cut them down again we're not accounting for the cost of using that same forested land for anything else, like a forest which is a great carbon sink. Instead burning wood pellets is considered renewable until you consider the cost of using that land for something else in which case it isn't a renewal resource.

Burning wood pellets is carbon neutral. Any forrest is a great carbon sink until it matures and it saturates, i.e. growth reaches replacement equilibrium and old trees/growth decay, releasing the CO2.

This is not taking in to account the fossil fuel usage for growing wood, transporting it and processing it to pellets.

Biofuels rarely make sense, unless we can get the biomass as a side-flow from some other process. And that kind of flows are quite limited compared to our energy needs.

Re: Big agriculture mislead the public about the benefits of biofuels

#133

Post by bluGill »

jkhdigital wrote: post #131
jbstack wrote: post #115

Earlier quoted context omitted.

"People aren't going to starve to fill their gas tank so you need to grow more corn to offset that used for biofuel. To do that can require destroying other carbon sinks (wetlands are the example given, sometimes dried and then burned) to turn them into fields" This doesn't make any sense to me. With petrol, you are transferring carbon from a store to the atmosphere every time you use it for energy. With a wetland, y…

Except that industrial-scale agriculture in general requires quite a bit of exogenous petrochemical inputs—not just the fuel to power the machines that do the work, but also the fertilizer.

Still far less carbon than used for gasoline

Re: Big agriculture mislead the public about the benefits of biofuels

#134

Post by jkhdigital »

passwordoops wrote: post #124
lazide wrote: post #46

Earlier quoted context omitted.

No they aren’t. Biofuels in use, keep atmospheric carbon neutral. Fossil fuels increase atmospheric carbon. Now, if we did make biofuels and reinject them into the ground, yes it would reduce atmospheric carbon. But neutral is strictly better than increasing, regardless yes?

"Biofuels in use, keep atmospheric carbon neutral." No they do not. The accounting generally doesn't take into account the full emissions of agriculture, which for corn is particularly carbon intense. Not to mention the downstream pollution impacts of over fertilization, such as coastal dead zones

This is the salient point that is glossed over without so much as blinking.

To get 1J of biofuel-based fuel, how many J of fossil fuel is burned? If it’s like 0.9J then you really have to ask how much carbon is released when turning carbon sinks into farmland, because it will take many many crop cycles to recoup that from biofuels.

Re: Big agriculture mislead the public about the benefits of biofuels

#135

Post by mapt »

tzs wrote: post #40

> Why would growing corn for ethanol and burning it in an engine be any climate-friendlier than growing that same corn for food and burning an equivalent amount of gasoline in an engine? The carbon absorbed in the field wouldn’t change; neither would the carbon emitted from the car. If the only difference was that producing ethanol emitted much more carbon than producing gasoline, where were ethanol’s benefits? Where…

Yes, that is indeed what was sold to us 30+ years ago. This background context is in the article; The rest of the article is about how that was a lie.

By about 20 years ago we understood that this was nonsense, that farm equipment and transportation infrastructure for corn cultivation chugs diesel, that somewhere between half, all, or twice (depending on study) the fossil fuels saved by corn ethanol would be burned to produce it.

Corn ethanol and soybean biodiesel suck. Sugarcane ethanol works with high EROI. WVO biodiesel is almost pure profit. There were suggestions that cellulosic ethanol (switchgrass, miscanthus) and algal biodiesel could be productive enough to be worthwhile, but they have not taken over, and subsidy has been directed consistently to boosting existing corn producers in order to win the Iowa Caucus.

Re: Big agriculture mislead the public about the benefits of biofuels

#136

Post by brabel »

dherikb wrote: post #120
Cthulhu_ wrote: post #118

Earlier quoted context omitted.

What crops are those, and do they grow in the same climates and soils as corn does at the moment?

Sugarcane, I believe.

Yes sugar cane is much cheaper and efficient. But you need very warm climate to grow it. Brazil has that and uses sugar cane for the most part. The USA does not so it uses what grows well in its interior , which is corn.

Re: Big agriculture mislead the public about the benefits of biofuels

#137

Post by mapt »

jayd16 wrote: post #44
tzs wrote: post #40

> Why would growing corn for ethanol and burning it in an engine be any climate-friendlier than growing that same corn for food and burning an equivalent amount of gasoline in an engine? The carbon absorbed in the field wouldn’t change; neither would the carbon emitted from the car. If the only difference was that producing ethanol emitted much more carbon than producing gasoline, where were ethanol’s benefits? Where…

Yeah, seems like they're forgetting the part where they need to bury the corn in bedrock to keep the carbon sequestered.

This is such an off-base critique that it seems like deliberate trolling. The biofuel renewable carbon cycle takes carbon from the air, and burns the carbon once it's in the form of ethanol. It stops taking carbon from the ground and putting it into the sky.

The problem in corn's case, the reason none of this works, is you need to burn lots of fuel to produce corn. LOTS of fuel. Enough that you could barely (in some studies) or not even (in others) produce more fuel than you burned.

If you electrify your farming you don't have this problem. A far-future use-case is that we have eliminated 95% of fossil fuel use, and use solar-battery-powered tractors, trucks, and combines to harvest biofuels in order to fuel long-haul aviation and certain other legacy hardware that proved difficult to electrify.

Re: Big agriculture mislead the public about the benefits of biofuels

#138

Post by bluGill »

zekrioca wrote: post #82
febusravenga wrote: post #78

Earlier quoted context omitted.

But corn is _stored_ energy that can be used at any time. PV is energy ar the current moment. Seems like this 20x loss the cost of storage... Interesting take though, I'm not saying that growing corn is best way to "produce stored energy", but in your comparison it's almost like direct competition to for PV + batteries of any sort.

Batteries.

Not nearly as energy dense. Useful for some applicatons but liquid chemical fuels deliver more energy when space or weight are factors - despite the inefficiency.

Re: Big agriculture mislead the public about the benefits of biofuels

#139

Post by lithos »

in_cahoots wrote: post #7

I read the whole article and I still don't see how Big Ag misled anyone. I may be misunderstanding, but it seems that the author is trying to differentiate between growing corn for food vs growing the same corn for ethanol. I assume the entire reason the lobby exists is that farmers want to grow corn for food and ethanol. But the researcher lost interest before proving anything around there. Maybe ethanol is actually…

There are some loose numbers tosed around like agricultural ethanol being 2x the carbon emissions of big oil.

While not circled around to properly destroying a wetland for farming, is also destroying a far more permanent carbon sink than a farm.

-----

IMO the article is tripping over itself to tell a story and cares about that story far more than factual information.

It could even help for some types of people, even if it's likely painful for the people reading from here.

Re: Big agriculture mislead the public about the benefits of biofuels

#140

Post by 7952 »

tzs wrote: post #40

> Why would growing corn for ethanol and burning it in an engine be any climate-friendlier than growing that same corn for food and burning an equivalent amount of gasoline in an engine? The carbon absorbed in the field wouldn’t change; neither would the carbon emitted from the car. If the only difference was that producing ethanol emitted much more carbon than producing gasoline, where were ethanol’s benefits? Where…

Ultimately what matters is the total amount of carbon in the atmosphere. Biofuels could help or hinder that effort. It all depends on the wider system.
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