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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

#171

Post by circlefavshape »

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.

hmmm ... but forests don't actually sit there for millions of years, right? and either way soils get eroded and ultimately end up on the ocean floor

https://ijw.org/wild-carbon-storage-in-old-forests/

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

#172

Post by no_wizard »

voxleone wrote: post #165

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 int…

Assuming all this about Brazilian ethanol is true, the real question for me is scale. The US consumes an enormous amount of gasoline every year compared to just about any other country. That’s what I’m curious about.

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

#173

Post by analog31 »

voxleone wrote: post #165

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 int…

At what rate do they produce degraded pasture land? Is it renewable?

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

#174

Post by thelastgallon »

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…

>Where the carbon comes from matters. Your underlying assumption is carbon is required. We could use the same land for solar panels. 40 million acres are used to grow corn for ethanol subsidies (out of 93m total). If we use these 40m acres for solar, Annual Energy Production (in watt-hours): 52,272 terawatt-hours (TWh)

To put that in context: The total electricity consumption of the U.S. is about 4,000 TWh/year. The energy generated from 40 million acres of solar panels could theoretically meet U.S. electricity demand more than 13 times over.

But, we'll need a lot less energy when we use solar/wind. We only need a third of the energy we use today, > 65% of the energy is wasted. So, solar panels on the same land used for ethanol production (and subsidized -- which is a lose-lose-lose idea) can produce 39x times US electricity demand (assuming ChatGPT calculation is correct).

When we produce this much electricity from solar, without fossil fuels, we'll also save 40% of water withdrawals. According to the U.S. Geological Survey, electric power generators are the largest source of U.S. water withdrawals and account for about 40% of total water withdrawals in the United States:https://www.eia.gov/todayinenergy/detail.php?id=37453

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

#175

Post by trollbridge »

analog31 wrote: post #173
voxleone wrote: post #165

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 int…

At what rate do they produce degraded pasture land? Is it renewable?

Brazil is a big place, and growing sugarcane properly actually regenerates the soil, such as if no or low till techniques are used (which are popular in Brazil).

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

#176

Post by 9rx »

lazide wrote: post #146
jkhdigital wrote: post #134

Earlier quoted context omitted.

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.

That is the implementation detail that makes the whole thing a scam, yes. None of that is fundamental to bio-fuels, but rather a property of it being cheaper to do it that way in our current fossil fuel economy, and people not being interested in looking all that closely because they don’t really care.

What is not factored into the above is how much is going to be grown anyway. Corn yield in particular can quickly surprise you. Even if you try to only grow enough for food, there will be years where you still have way more than you can handle.

That is why we started producing corn-based ethanol. It wasn't intended to see people grow corn for it, but rather clean up the unmanageable excesses realized in the due course of growing it for food-based reasons that otherwise would have been left out to rot. In that vein, J is insignificant as it is spent either way.

The problem is that humans aren't very good at moderation. A little ethanol production is quite sensible, but once humans get it into their head something might be sensible in small doses they have to take it to a ridiculous extreme... You see that in everything.

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

#177

Post by trollbridge »

throwaway_5633 wrote: post #123
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…

One of the things that concerns me most after studying agriculture for a couple of years is that people may definitely starve to fill other people’s gas tank. A lack of arable land is imminent and high income people at the gas pump, or eating meat (same economics) may well outspend those who don’t have enough food. Part of food inflation is attributed to biofuels. https://en.wikipedia.org/wiki/Ethanol_fuel_in_Brazil

Hasn’t happened in Brazil at all, where food is quite affordable, and they’re a gigantic food exporter too.

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

#178

Post by krainboltgreene »

trollbridge wrote: post #175
analog31 wrote: post #173

Earlier quoted context omitted.

At what rate do they produce degraded pasture land? Is it renewable?

Brazil is a big place, and growing sugarcane properly actually regenerates the soil, such as if no or low till techniques are used (which are popular in Brazil).

I don’t believe there’s any evidence to suggest sugarcane regenerates soil. In fact I can only find evidence to the contrary.

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

#179

Post by trollbridge »

9rx wrote: post #166
raverbashing wrote: post #104

Earlier quoted context omitted.

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…

Excess corn crops in the 1800s were used to make (corn mash) whisky.

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

#180

Post by bgwalter »

Biofuels get the subsidies so that in case of a major crisis like war there is enough food and some fuel for essential services.

It is not that hard to understand. It is possible that studies were tweaked to support another narrative, but farm subsidies always serve strategic interests.

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