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Corn Ethanol Is Of No Use

forbes.com

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Re: Corn Ethanol Is Of No Use

#21

Post by mikeash »

i80and wrote: post #5
afhdshufdufdo wrote: post #4

Most new cars will be electric in 10 years. Then instead of oil, coal or nuclear (power plants) will be the primary power source and ethanol for automobile fuel will be a minor issue.

I agree with you, but battery technology has some pretty serious problems for cars that can't be ignored. How do you deal with the replacement cost and lemon risk (battery leasing and warranties). For me, cars are for road trips. How is that usage addressed (open question, aside from putting superchargers everywhere usable for all electric cars). How do you deal with the power grid costs? Power mains aren't build to…

For road trips, rent a suitable car. The idea that you should modify your purchase of a daily driver to accommodate an activity you do once or twice a year is common, but strange.

Re: Corn Ethanol Is Of No Use

#22

Post by ams6110 »

randomdata wrote: post #16
cheepin wrote: post #2

How did these laws pass (besides lobbying from people growing corn)? I wasn't following too closely at the time.

Leading up to that time we had corn coming out of our ears and elevators were quite literally leaving it out to rot. The energy was already spent, ethanol was just a plan to recapture it. It wasn't completely misguided.

There was a good bit of uncritical, emotion driven thinking as well. Corn == bio == green != oil thus must be good.

Re: Corn Ethanol Is Of No Use

#23

Post by hueving »

bruce511 wrote: post #19
i80and wrote: post #5

Earlier quoted context omitted.

I agree with you, but battery technology has some pretty serious problems for cars that can't be ignored. How do you deal with the replacement cost and lemon risk (battery leasing and warranties). For me, cars are for road trips. How is that usage addressed (open question, aside from putting superchargers everywhere usable for all electric cars). How do you deal with the power grid costs? Power mains aren't build to…

Your other into aside, which certainly are important questions; >> for me, cars are for road trips... It's probable that many people have taken a road-trip holiday at some point in their lives. Some percentage of people do it regularly. However anecdotally I would suggest most people have not. Outside the US conditions for the road-trip holiday are not as prevalent. In high-density Europe for instance there are easie…

>some people do, but they're a tiny minority

Do you have any citations for that? I do a trip once a year or so of about 1000 miles and it never really surprises anyone when I tell them that so it must not be that uncommon.

Re: Corn Ethanol Is Of No Use

#24

Post by beloch »

First off, let's take a moment to appreciate what we've got. Gasoline is fantastically dense in energy. Approximately 46 MJ/kg! Ethanol is about half as energy dense, which is why it is usually mixed with petroleum gasoline. Engines must be specifically designed to operate on pure ethanol. Going from the numbers quoted on Tesla's site, their Roadster's lithium ion battery packs have an energy density of 0.456 MJ/kg. If you want to have the same range, electric vehicles have to devote over a hundred times more weight to batteries than gas-guzzlers do to their tank contents. To make matters worse, spent gasoline weighs nothing while spent batteries weigh the same as full batteries. Electric motors are mechanically simpler/lighter and innovative design can carve even more weight off of new vehicle designs, but there is a very good reason why cheap, long-range pure electric vehicles are still a ways off. Lithium ion batteries are also pretty nasty things to produce in terms of environmental impact. It's debatable if a plug-in electric vehicle run off of solar/wind/etc. power actually has less impact than a small gasoline car does at present. If the power used comes from coal then an electric car is actually a huge step in the wrong direction. Also note that the U.S. is not a major producer of Lithium, so dependency on foreign nations is not broken by switching to electric cars.

If corn derived ethanol is worse for the environment than petroleum derived gasoline, the only reasons to use it are economic. If it's cheaper, people will likely use it. (Nevermind that so-called "biofuels" often command a premium because people think they're environmentally friendly!). However, if biofuels are bad for the environment, electric cars are bad for the environment, and other alternatives are not yet commercially viable, what does that leave? Well, sadly, it means stop driving so much! Use public transit. Bike. Walk. Carpool. Stop throwing irrational hissy fits about pipelines meant for safely transporting petroleum if it's the least harmful option that's currently available.

Hopefully better electrical storage technologies will become available before too long. Nanomaterials do potentially offer ways to make capacitors powerful enough to eclipse current chemical battery technologies. This is years or decades off into the future unfortunately. I'm not saying all this to be a drag, but most people really think battery technology has come a lot further than it actually has. Gasoline is still pretty darned useful stuff.

Re: Corn Ethanol Is Of No Use

#25

Post by tezza »

I wouldn't say no use.

Instead I'd say no current use.

Some power uses cannot be electrified ( nuclear powered airplanes ? )

David Mackay estimated[1] that if there was no fossil fuel left / consumed we'd need to use 12% of our arable land for biofuel as:

"There are a few essential vehicles that can’t be easily electrified"

[1] http://www.withouthotair.com/c27/page_204.shtml

Re: Corn Ethanol Is Of No Use

#26

Post by zhte415 »

randomdata wrote: post #15
tim333 wrote: post #10

The whole corn ethanol thing amazes me. How they can throw $30bn a year into a program than makes the environment worse is surprising. I realise the recipients of the cash they pay a proportion back to the politicians to keep the thing going. But really - a $300bn or so cost over the life plus producing hunger in poor countries by burning the food? I'm surprised the political system is actually quite that bad. On the…

As someone who grows corn (in a country where the crop is not subsidized, I might add), the way I see it is that we're going to grow the corn anyway, so turning it into fuel is better than letting it rot away as was happening before the ethanol program was put into effect. The problem is that our crops need to be rotated. Corn seems to be the only crop that fills the gaps that is also compatible with the equipment we…

I'm curious about corn rotting.

I live in a country that produces quite a lot of corn. Some is sold as fresh produce, but any surplus ends up on the rooves of farmers' houses, dried, consumed during the winter as the major starch. The husks are used for fuel - quick and hot burn stir fry. There is no need to let corn rot.

Why let it rot?

Re: Corn Ethanol Is Of No Use

#27

Post by stephen_g »

gscott wrote: post #9
mixmastamyk wrote: post #8

There are reasons besides environmental ones to encourage use of biofuels (hopefully made from more than corn). One is that ~10% less oil has to be imported during production shortages. It's not a complete solution, but a minor part of one.

My wife started using E85 fuel her gas mileage went from 22mpg to 17mpg. Even though there was a subsidy on the fuel she ended up having to purchase more. She has since switched back to regular fuel.

Yeah, I did a project on this sort of thing in Uni with E10. We found that the few cents less it costs per litre at the pump was not enough to pay for the extra fuel you had to buy to make up for the fact that there is less energy in the fuel (this is in Australia - pretty sure that we have subsidies here too).

It was a few years ago, but I remember looking at research saying something like it not being really sustaiable (despite being renewable) because it requires too much energy to produce it for what you get out of it.

Re: Corn Ethanol Is Of No Use

#28

Post by dredmorbius »

mixmastamyk wrote: post #8

There are reasons besides environmental ones to encourage use of biofuels (hopefully made from more than corn). One is that ~10% less oil has to be imported during production shortages. It's not a complete solution, but a minor part of one.

Biofuels simply aren't scalable to any appreciable fraction of present-day petroleum utilization in advanced industrial nations. For crop-based fuels such as ethanol, productivity is well below 100 gallon/acre. Scale that to the billions of barrels of oil consumed annually, and you'd need several times the present-day arable land of the US to produce the fuel used now.

Looking at primary productivity worldwide, humans already consume 14% of all plant growth. Our fossil fuel utilization would be another 21% of this, according to Jeffrey Dukes in "Burning Buried Sunshine", a 2003 paper (http://globalecology.stanford.edu/DGE/Dukes/Dukes_ClimChange...)

I see some promise in the US Navy Research Lab's electricity-to-fuels project, using seawater as a feedstock for both hydrogen and carbon. That could scale to national levels of production with only a few square km of plant, and about 40,000 km^2 of solar arrays (about 200 km on a side). Given alternative proposals for fossil fuel replacements, it's vastly further into the plausible space.

For some ballpark numbers:

• Conventional crop biodiesel or alcohol typically cite about 100 gallons/acre-year

• Typical algae biodiesel yields are 10x that, or around 1,000 gal/acre-yr

• I've seen claims of 10x that, for 10,000 gal/acre-yr

Assuming that last is possible, you'd need 124,000 km^2 (350 km on a side), or 30 million acres (about 7% of present US cropland) to supply all present petroleum use. That's a very highly engineered 350km square, mind, with a bunch of goop that needs to be fertilized, wastes removed, protected from pests, harvested, dewatered, and processed.

Some incidental biofuels utilization? Sure. Most of our fuel from it at present volumes? Not gonna happen.

Re: Corn Ethanol Is Of No Use

#29

Post by Shivetya »

tim333 wrote: post #10

The whole corn ethanol thing amazes me. How they can throw $30bn a year into a program than makes the environment worse is surprising. I realise the recipients of the cash they pay a proportion back to the politicians to keep the thing going. But really - a $300bn or so cost over the life plus producing hunger in poor countries by burning the food? I'm surprised the political system is actually quite that bad. On the…

Because as with most things related to the environment, if you disagree with their assessment your a oil company shill. If the environmentalist claim something is you are not allowed to say otherwise.

that and Congress loves the farm lobby, Congress guarantees them income and they in turn feed it back into approved groups.

Re: Corn Ethanol Is Of No Use

#30

Post by afhdshufdufdo »

afterburner wrote: post #13
afhdshufdufdo wrote: post #4

Most new cars will be electric in 10 years. Then instead of oil, coal or nuclear (power plants) will be the primary power source and ethanol for automobile fuel will be a minor issue.

And renewables, which you casually dismiss. Solar panels are becoming on par with coal, and there are many other types of renewable energy as well.

I intentionally dismissed them because renewable energy is still a minor percentage of the total power produced in the world. Not counting biomass it is 6% according to http://en.wikipedia.org/wiki/Renewable_energy
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