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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

#161

Post by patwolf »

motorest wrote: post #91
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…

> 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. The key point is that biofuel replaces fossil fuel. Meaning, instead of having a system that inputs carbon into the environmen…

> Surely you are old enough to hear the comotion about switchgrass

I hadn't heard "switchgrass" since GWB mentioned it in his State of the Union years ago. Did it end up becoming a significant source of biofuel?

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

#162

Post by TomMasz »

Ah, E85. My wife's flex-fuel Chevy could use it, but it ran poorly and mileage noticeably dropped. It wasn't worth the meager savings (it's usually more expensive now) over regular gas. I've always wondered about the environmental impact. It's clear now that it's not great. I'm not surprised.

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

#163

Post by lazide »

karolinepauls wrote: post #154
RivieraKid wrote: post #144

Earlier quoted context omitted.

A forest or wetland is a carbon sink only in the growth phase. In a long-term equilibrium, it's carbon-neutral, like biofuels.

The world is more complicated than a 17th century lab experiment in combustion. Forests sequester carbon through forest fires producing charcoal. Humans could actually cut down old trees, dry them, and convert them to charcoal later used for soil enrichment. Wetlands capture carbon by incorporating wood from dead trees in anoxic conditions. > When plant productivity exceeds decomposition, net soil carbon accumulation…

Bwahaha, this is so ridiculous.

Show me the megatons/year of charcoal being produced by the worlds forests eh?

We could process them yes, but we can also just make them into timber - or burn them for energy. Or just bury them somewhere under a bunch of clay. Oh, and now we’re back to this thread.

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

#164

Post by RivieraKid »

circlefavshape wrote: post #152
RivieraKid wrote: post #144

Earlier quoted context omitted.

A forest or wetland is a carbon sink only in the growth phase. In a long-term equilibrium, it's carbon-neutral, like biofuels.

I don't think that's true - my understanding is a forest produces soil continuously, and that's a carbon sink

This was true in the carboniferous period, when the organisms able to metabolize the lignin in trees haven't evolved yet, so the dead trees ended up as coal.

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

#165

Post by voxleone »

While it's true that Big Ag in the U.S. has oversold corn ethanol as a climate-friendly alternative, it's important to distinguish between types of biofuels. Not all ethanol is created equal.

Take Brazil, for example. Their ethanol program is fundamentally different. It's based on sugarcane, not corn, and it has a spectacular EROI (Energy Return on Investment) of about 8:1. That means for every unit of energy put into producing it, eight units are returned. By contrast, U.S. corn ethanol barely breaks even, with an EROI around 1.3:1 to 1.8:1.

Brazilian ethanol also sidesteps many of the land use and food diversion issues that plague U.S. biofuels. Sugarcane is mostly grown on degraded pastureland far from the Amazon, and it doesn’t displace staple food crops. Plus, the leftover biomass (bagasse) is burned to power the refineries themselves, making the process close to energy self-sufficient.

The Brazilian model shows that biofuels can work—but only under the right agricultural, environmental, and economic conditions. The U.S. corn ethanol lobby essentially hijacked the "green energy" narrative to push something that mostly benefits Big Ag subsidies and corn states, with questionable climate gains.

So yeah, skepticism about biofuels is warranted—but we should be careful not to throw out the good examples with the bad.

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

#166

Post by 9rx »

raverbashing wrote: post #104
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…

That being said, growing corn for fuel ethanol is stupid. Other crops are more efficient (Unless we find a way of turning the whole plant into fuel)

The trouble with corn is that its yield band is huge. Get a good growing year and suddenly you have twice as much as you need — and more than you can store, leaving it out to rot. Recapturing that energy as fuel instead of disappearing waste heat is a win and what corn-based ethanol was introduced for.

The trouble with humans is that they aren't very good at moderation. As soon as they see a little opportunity to do something good they take it to the extreme, to the point that it is no longer good.

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

#167

Post by RivieraKid »

karolinepauls wrote: post #154
RivieraKid wrote: post #144

Earlier quoted context omitted.

A forest or wetland is a carbon sink only in the growth phase. In a long-term equilibrium, it's carbon-neutral, like biofuels.

The world is more complicated than a 17th century lab experiment in combustion. Forests sequester carbon through forest fires producing charcoal. Humans could actually cut down old trees, dry them, and convert them to charcoal later used for soil enrichment. Wetlands capture carbon by incorporating wood from dead trees in anoxic conditions. > When plant productivity exceeds decomposition, net soil carbon accumulation…

Dead trees and other plants in a mature forest are decomposed and in that process, carbon is released back into the atmosphere.

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

#168

Post by Geee »

pfdietz wrote: post #156
circlefavshape wrote: post #152

Earlier quoted context omitted.

I don't think that's true - my understanding is a forest produces soil continuously, and that's a carbon sink

Soil too eventually reaches an equilibrium where carbon injection and carbon oxidation are in balance. If what you thought was true, imagine a forest sitting there for millions of years. Where would this permanently sequestered carbon be going? Soils do not become unboundedly thick.

Well, that's what oil and coal are. Oil is formed from marine biomass, and coal is formed from plants.

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

#169

Post by 9rx »

b112 wrote: post #108
burnt-resistor wrote: post #90

Earlier quoted context omitted.

Grain overproduction is also a significant driver of climate change. Fossil fuels, meat, and GMO monocultures aren't ecologically sustainable in current form, they continue because of capture of factions of governments by corrupt lobbying interests who threaten elected officials into driving more cash and favorable regulations their way.

People need to stop pointing the finger at food production, with such massive blinders on. Food "overproduction", are you actually serious? Are people so removed from farming, and food production, that they think it's a simple thing? Plant X food, get X food? Absolutely not! Even with irrigation, there are years with drought, yes even in the West. There are years that are too cloudy, or too sunny (yes, too sunny is a…

> and some events at harvest time can wipe out crops entirely!

And that swings both ways. Last year, with the stars aligning just right, the corn yields around here were ~100 bushels per acre higher than even our most optimistic pre-harvest estimates. That is an incredible amount of unexpected extra product. Corn especially has a huge, unpredictable yield band.

Which, of course, is exactly why we started producing corn-based ethanol. To buffer the periods of uncontrollable excess — where the previous alternative was to see it rot away.

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

#170

Post by griffzhowl »

RivieraKid wrote: post #144
griffzhowl wrote: post #121

Earlier quoted context omitted.

I think the idea is that the wetland or forest or whatever is a carbon sink in the sense that they have a net negative effect on carbon in the atmosphere each year. Growing corn and then burning it would at best be net zero if no further atmospheric carbon were produced by the production processes, fertilizers etc., which it is. So the differences between the two scenarios is net negative versus net positive atmosphe…

A forest or wetland is a carbon sink only in the growth phase. In a long-term equilibrium, it's carbon-neutral, like biofuels.

Most of the land in question isn't a mature ecosystem in equilibrium, and if it is there are other arguments against turning that into cornfields. But let's say the worst case is that it's carbon neutral.

The point is that biofuel production isn't carbon neutral. Maybe it could be theoretically, but in practice it takes energy inputs in the production process like in the fertilizers, processing of crop into fuel, and transport/distribution, which makes it net positive for atmospheric carbon.

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