The problem with alcohol as a fuel

[DanG]

I've been doing a little reading and a lot of thinking about alternative fuels lately.  It seems that the major objection to alcohol is the notion that it takes more energy to produce it than you get from it.  Now, I don't buy into that idea at all, but you can't escape the fact that it does take energy to make alcohol, so any way we can mitigate that energy consumption would be a plus.  I've come up with a couple of ideas that seem viable, but I don't know if they've been tried, or may be already in use.

The first idea is to use solar energy to generate part of the heat for the distillation process.  The major part of a still's energy requirement is to heat liquids, and outside of drying clothes, heating liquids is the simplest and cheapest use for solar energy.  It takes very little outside fuel to heat 160 degree water to the boiling point, at least a whole lot less than to heat 54 degree water.

The second idea is one I mentioned on another thread, and involves capturing excess heat from other operations.  Power plants are the most obvious source of waste heat that I can think of, but many other industries are spending big bucks to get rid of excess heat.  Why not co-locate an ethanol plant with a power plant and take advantage of the excess heat? 

At the other end of the alcohol contraversy is the fuel it takes to produce the materials needed.  The naysayers skew the statistics way out of proportion, but again, you can't escape the fact that it requires some.  Methane would be a good choice here.  The problem with methane is the lack of portability.  It takes a lot of it, about twice as much as Natural Gas, and it is less stable, so it is better used in a localized application.  The farm is the ideal environment for it.  The material is laying about all over the ground, and disposing of it is usually a problem.  Leaving it lay causes pollution of streams and releases massive "greenhouse gasses" into the air.  Digesting it and capturing the methane is simple and cheap and will provide fuel for farm vehicles, including the tractors that are used to grow the materials for alcohol.  Where is the downside here?

Y'all are more than welcome to shoot me down on any of these ideas.  If there is some reason they won't work, I'm all ears.  If they are already being used in any significant scale, I'll be tickled to death.  All I ask is that we try to keep politics out of the discussion.

[Fla._Deadheader]

 I can't comment, because, mostly I'd hafta agree with you, but, you never agree with me, so, THERE. 


   Cheese whey is a terrific product for making alcohol. There is heat used in cheese making, right

  Guess where most cheese comes from???  Dairy farming areas. Same as the Cow fuel.

 

[johnjbc]

This makes it even better    http://en.wikipedia.org/wiki/Ethanol#Physical_properties
You don't need to heat it to the boiling point of water. Just till the alcohol boils 78.4 °C

[BigTrev]

DanG DanG, that actually makes a lot of sense.

I like the idea of using byproducts as the energy sources, no extra resources used means no greeny intervention.

The only problems I could see would be intergration of the new idea with existing power plants etc and the potential hazard of thousands of gallons of alchoholic water zooming along above a steam turbine. But I suppose that is no more hazardous than the stuff they are allready working with.

Heh at least if there was an accident at a power plant the workers wouldn't all glow afterwards, they'd just get a hangover 

But seriously, its a really good plan. All you need now is a couple of billion bucks and a deck of cards

[stonebroke]

deadheader

you have a grat idea. In Fact inNY rhe cheese plants are all switching over as fast as they can. The problem is that whey used to be a energy source for the cattle feeders up here and now you can,t get it.  I guess that just proves energy is energy ,You just have different forms.

Stonbroke

[DanG]

Trev, I don't see integration into the power plant as an insurmountable problem.  I was thinking more of piping the excess hot water out of the plant, rather than the alcohol into it. 

There is a golden opportunity just south of here to incorporate the whole shebang in to one operation.  They're planning to build a new coal-fired power plant next door to a paper mill, and using the dirty water from the paper mill to generate the steam for the power plant.  While they're at it, they could build a cellulosic methynol plant on the same site and recycle the excess heat from the power plant.  This whole thing is located in the middle of several million acres of pine trees.

BTW, on a related note:  My neighbor, who is an Agri-scientist at the Ag Experiment Station here, told me they have planted a stand of Cottonwood trees for the purpose of fuel alcohol production.  The trees are 3 years old and over 20' tall.  These trees are way outside of their natural range, but appear to be thriving.  Interesting experiment, I'd say.  The major goal is to find the most cellulose per acre/per year.  They'll have to do some major growing to beat Loblolly pine.

[submarinesailor]

DanG,

One thing that makes it a little hard to integrate an alcohol plant with a power plant is the condensation point of liquids in the waste steam.  If I remember correctly, when you drop the waste heat below 328 degrees the sulfur starts to condensate out as an acid.  Eating up the exhaust system big time!!!!!!!!!!

Also, most power plants have heat recovery systems built into them.  Example: If you use an economizer to transfer the waste heat from the exhaust output to the boiler feed water, you can increase the boiler’s efficiency by 1% for every 100 degrees you reduce the waste heat.  Remember, the more efficient power plant owners can operate their plants, the lower there energy cost are.

If all that said, I totally agree with you about co-locating them - if you can do it without robbing Pete to pay Paul.

Bruce

[Texas Ranger]

 All I know is that the Scotch folks, the Irish, and Jack Danial's have produced alcohol for years, and I really think they have it down, for me, anyway.

[Ron Wenrich]

I'll throw a few more things for you to congitate.

What kind of proof are you trying to get down to?  You don't need 190 proof alcohol to use as a fuel.  80 proof will do fine.  You have to have larger jets, but it makes a good heating fuel. 

Who says you need corn to make alcohol?  I have yet to hear anyone talk about sugar beets.  And there are tons of food that goes to waste each day that can be made into fuel.  Bakeries and candy plants throw away bunches of stuff with starches and sugars.  It would be good to recycle it into fuel.  You probably could do it with regular old garbage.

I'm thinking the boiling point is 168° for alcohol.  A solar still is not out of the question.  As pointed out, trash steam is usually too hot for distillation. 

Since alcohol vaporizes at such a low temperature, and a car engine runs at a higher temperature, would it be to any advantage to vaporize it before injecting it into the engine?  Would that increase efficiency?  It seems like it should be fairly easy to do, except in the really cold places.

[Fla._Deadheader]

 Sugar Beets and Sugar Cane are the two highest producing crops per acre for Ethanol.

[pineywoods]

Like so many other things, the devil is in the details. At first glance alcohol looks like a viable fuel, but there's a whole bunch of little gottcha's. alcohol has a natural affinity for water, will even absorb water from the atmosphere under some conditions. Alky plus water plus aluminum or many types of plastic equals bunches of corrosion. It boils at about 165 degrees or so. Ever wonderhow hot it gets under the hood?? vapor lock city. Cold temps are also a problem. Below about 35 F it won't vaporize, ie cold weather starting is a booger. Had a friend who converted an old VW beetle to run on alky. He had to put a small electric heater in the carb to get it started on cool mornings, and thats in the sunny south. Don't work worth a darn in a fuel injected system either. As for heating above 170 f and running the engine on the vapor, got a good story about that too, but it can wait for another post...

[Fla._Deadheader]

 What about all the race cars that use Ethanol

[DanG]

Great input, folks!  The systems I proposed are full of pitfalls, and I know that.  But, were there no pitfalls in the development of petroleum fuels?  Some of the best minds in the world have been working on them for over a century.  The biggest stumbling block they have run across is the fact that the supply is finite.  It has been proven that "gasoline" engines will run on alcohol or methane.  It is also proven that deisel engines will run on vegetable oil.  Contemporary wisdom tells us that we cannot totally replace petroleum, and I accept that...for now.  We have only just begun to try, yet we have production cars that will run on 85% ethanol and 15% petroleum with no problems.  That sounds pretty spiffy to me, since we can only grow about 25% of our energy "needs" with the current technology.  I can only imagine what the figures could look like if we concentrate on efficiency and conservation.  I firmly believe that if we give it a good try, we can be at least independent of foriegn oil, if not fossil fuels altogether, within my expected lifetime.  All it takes is a little bit of common sense.

Submarinesailor, yours was exactly the type of input I was hoping for.  To be sure, my offerings were pretty simplistic, and there are bound to be many hurdles to leap.  One thing is for sure, though...if there is an extra BTU to be eeked out for an extra nickel's profit, those power plant executives will be glad to learn of it.

[Don_Papenburg]

Some of the biggest stumbling blocks we face with renuables are voted into office by us and then the bueracrats that they hire to run the regulatory agencys (Read money generators)
  For a small farm to install a methane digester one would have to get permits and pay fees to the EPA and local fee generating regulators building permits health department,etc   .   If we could get rid of some of those problems the others would meld right in.

[DanG]

There are political implications to be sure, Don.  We just have to realize that the politicos and their bureaucrats serve at our pleasure, and make that stick at the polls.  As far as regulation is concerned, we need a certain amount of it.  One guy, 25 years ago, polluted an entire river system down here by illegally recycling old car batteries and dumping the waste in the creek.   The river is still polluted from that, today.  Such as that is why the EPA exists.

There are Government incentive programs to help people develop alternative energy solutions, including methane digesters.  A couple of years ago, our county agent recieved and distributed 5 methane digesters to farmers, courtesy of the US Government.  I'll check next week and see how the program is coming.

[WDH]

I like the idea of using trash to generate alcohol for fuel.  The problem is location.  Most folks object to siting these type of operations in their backyard. 

We do need creative thinking.  Good going, Dang .

[Ron Wenrich]

NIMBY will always be a problem.  We had several ethanol plants shot down because of it.  You would think people would welcome something like that.  They're also shooting down wind generators. Seemingly, status quo is the way to go. 

We've had several companies interested in putting in stills.  But, a lot of the economics didn't work out.  It seems like they stretched things a tad to make it work.

Farmers should be able to capture methane fairly easily.  Especially those using the lagoon system.  I have seen where they were using the captured methane to run generators and sell back to the grid.  We're also pulling methane out of the local dump and generating electricity.

 

[DanG]

I've never been around an ethanol plant.  Is there a serious odor problem with them?  My thought is that if it stinks, then something they could be using is getting away from them.  I can't imagine it smelling any worse than an oil field, anyway.

[Ianab]

Guess it depends what you are fermenting?
The dairy factories here push most of their whey into methanol production, but what they end up with is food grade... worth much more than fuel prices. Mmm... Vodka

[DanG]

Folks don't seem to mind having a brewery in their backyard, either.

One thing we have to keep in mind is that we are mostly limited to surplus, wasted, or previously untapped resources.  We can't distill all of the corn, or burn all of the veggie oil in the trucks, and we'll still need a little bit of wood to play with.  Also, we have to realize that most industries already have a use for much of what we think would be waste.  There are a lot of important by-products that most folks don't even know exist.

As we move into the age of renewable energy, we open the door to a whole new set of the same old problems, too.  I can just see the headlines in 2027: "Drought in Southeast to Drive Fuel Prices Over $10 by Labor Day."