ethanol ran generator?

How can I find a generator that runs on ethanol or modify one to do so? Any info is greatly appreciated!


To introduce myself since this is my first post I will say this forum is great! Wonderful knowledge, I have a aquaponic system in my greenhouse, meat rabbits and quail for GMO free meats and a worm farm under the rabbit pins for fish supplements along with BSF larva, trying to get where Im not buying pellets but not there yet. Just finished learning how a rocket stove can heat my greenhouse and produce ethanol!

Grant, I don't see ethanol as a good choice for stationary power generation... unless you happen to have a vast supply of very cheap fermentable sugars. If that's the case, then please share with us what you've got going on. If not, then there are many options that you should find preferable to ethanol.

Please share your experiences with meat rabbit/quail/vermiculture in the other sections.

Grant Fulcher : I too want to Know where you are getting your ethanol, For trading purposes its worth at least $10.00 U.S. per Quart, and you want to burn it up with gasoline less than $4.00 a gallon U.S. - I'm not Trolling -I just want to know ! thanks Allen L.

Grant Fulcher : I originally came to this forum page intrigued by the Title, I was going to suggest that you might want to check out the use of butanol in I.C.Engines, but drifted off of the subject, I would like to read more on this subject, share when you get a chance ! - Pyro - maticly yours, Allen L.

Thanks for all the reply's. I will start educating myself on alternative fuels as mentioned above to run a generator on. Alcohol can be a gas by david blume is convincing book that its a great back up, cheap and easy to produce like Brazil is implementing. I just want to be able to heat my greenhouse if the power and gas are off. Probably going with a natural gas/ propane one to start with. In an urban setting is it possible to produce butanol? Thanks for the lead, i will research it.

Grant Fulcher wrote:Thanks for all the reply's. I will start educating myself on alternative fuels as mentioned above to run a generator on. Alcohol can be a gas by david blume is convincing book that its a great back up, cheap and easy to produce like Brazil is implementing. I just want to be able to heat my greenhouse if the power and gas are off. Probably going with a natural gas/ propane one to start with.

If you have lots of cheap fermentable sugars, then making your own ethanol is not unreasonable. However, it should best be used as an automotive fuel to replace expensive liquid fuels (gasoline and diesel) - or used to make cocktails. For heating applications, natural gas is the best option if you have it available. The natural gas distribution system is very reliable. The best backup to natural gas that I can think of for heating a green house would be a rocket mass heater fueled by wood waste. See zaugstoves.com for one commercial example.

The following are some fuels for powering a stationary generator that I consider to be practical possibilities. The best options depend on what you have available and whether or not you're totally off grid or just looking for back up power:

-vegetable oil/biodiesel
-ethanol
-natural gas
-propane
-gasoline
-diesel
-wood

I have free sources of starch (sugar) available from both a potato chip factory as well as a dairy company that discards whey that I can turn into ethanol cheaply via a solar still as well as a solar-powered still.

I am very interested in an ethanol-powered generator.  I live on an island with ample sun, and my home is off the grid.

Does anyone have any leads on such a unit?

Thanks!

Aaron

Hi Aaron. Welcome to Permies!

You make an interesting proposal. I would love to see something like this in operation.

To start, I would suggest thinking about what work you want to accomplish with the energy. Think about what the end goal is, and work back from that. Is it the best way to get the job done (aside from being a cool project)?

Assuming an ethanol-fired generator is a good fit, off the top of my head I can see two main challenges.

First, making and distilling ethanol to a level of purity that will run in an internal combustion engine. Basic distilling is simple enough. I wonder what's needed to get high concentrations?

Second, finding or modifying an engine to run on ethanol. I've heard that ethanol eats the fuel system seals on older engines. Also, there may be requirements for special additives, oil or other lubricants to replace those in gasoline (for example, special oil is required for propane fired engines). I can't speak to carburetor adjustments, other than noting that ethanol has less energy per volume of fuel.

I think this was done in Brazil and possibly Cuba maybe 40 years ago.

Phew, the more I look at the work to be done, the more I wonder if solar panels might be easier!

Well.....

I cant tell you where to buy a generator but I can tell you how to burn alcohol.

There are a ton of caveats, as you may imagine,
For starters anything less than 90 proof is too wet to burn reliably, 140 + proof is fuel grade, after 192 proof its considered rocket fuel,
Alcohol is horrifically corrosive, to steel or anything with the least ferrous content, even at low concentration as in B10 or B30 mixed petrol it easily eats through steel fuel lines, pot metal carburetor castings, filler necks, and fuel tanks. The reason automakers and politicians have embraced ethanol is its a more subtle form of planned obsolescence.
Alcohol has very low BTU content, fuel grade ethanol has around 12,500 btu per pound, (same as coal!), petrol is 19,000, this leads to power robbing inefficiencies, a 5hp motor actually putting out a max of 3.5 hp etc.


Soo....
To address these problems from bottom to top.
Start with a unit roughly 30% larger than needed, power can be regained by increasing compression ratio but that comes with its own caveats; (detonation, hard starting, and increased N0x emissions) a larger unit is just....larger! and can pass more btu's of fuel to larger pistons, with greater rotating mass, and a heavier flywheel, to make up for the loss of energy content.
In addition to a larger  unit, jet sizes will have to be increased, or spray ratios lengthened in duration, if your hacking a fuel injection system.
Nylon fuel lines, and polyethylene tanks, and PVC filler neck will stop storage corrosion, the addition of a top oil will retard corrosion....but it won't stop it! in manifolds and on cylinder walls and carb castings.
There are coatings that can be applied to the interior of metal tanks too, but its too easy to build a fuel tank of PVC, to make it worthwhile.

In practice this means after you buy your unit, buy a few extra carburetors and a handful of extra jets, a pin drill, and a drill set graduated in thousandths, remember there are three circuits in a carburetor (Idle, acceleration, and hi speed) and they must all be adjusted by guess, and by gosh, don't forget that fuel flow rates are affected by burrs, air bleed ratios, and filter obstruction.
Of the three most of the time an engine runs its idling, so perfect that, then move on to high speed tuning, and if the motor stumbles on the transition, the acceleration circuit needs increased.
Keep copious notes....or every time you do this, it will be a blind experiment.......

I have found building 5hp briggs race engines and converting mower engine that ethanol is a great fuel.  Ethanol has extra oxogen in it and aid in combustion.  It is simple for me to dyno a standard flathead 5hp briggs at 10hp running on ethanol. As stated before the volume of fuel needs to be about 1/3 more because of the less energy.  I have a selection of jets I predrilled so while tuning I can quickly get it set up.  Unlike gasoline ethanol can be ran slightly rich and still hold a good tune. Good quality silicone fuel lines will last many years.  The best thing to do is run it out of fuel when shutting it down.  I use 2 different gas caps on the fuel tank.  One is sealed with JB and the ether is left vented.  When not using the engine I just leave the JB sealed cap on the tank.  This keeps the water out of the fuel.  Water is the most damaging while mixed with ethanol.  It become acidic and causes corrosion in the carb because of the different type of metals used.  Ethanol will pull heat from your engine if jetted right will run much cooler.  On days below 50 deg it may need a shot of gasoline to get it to fire up, because the ethanol may not vaporize in the venturi of the carb. The oil in these engine I build never seems to get black.  The ethanol burns nice and clean.  Have fun with it.

I have been considering ethanol as part of an attempt at a fully closed system.

Burn the ethanol in atmosphere, which produces water and heat.
Use the heat to boil the water to steam and drive an alternator to get electricity.
Condense the distilled water in atmosphere using a long copper coil.
Drink it. Produce urine/nitrogen. Boil it in the same system or distill it with a solar box.
Use the clean water and nitrogen for growing sugar producing plants.
(along with a humanure system which is a closed system itself, which can also produce methane in a digester for more heat and water)
Turn those plants into more ethanol and food.
Chickens and rabbits can easily be added to this system.

My point kinda is that there are 2 substances both of which readily burn in atmosphere to produce water and substantial heat.
And both of those substances can be created from microbes and it is not very difficult to get them to do that.

maybe

It's an interesting thought experiment.

I'm not clear on how you plan to distill the enthanol to a burnable concentration. That requires a heat source.

Somewhere in the system you will probably need a heat source for cooking as well.

Regarding "Use the heat to boil the water to steam and drive an alternator to get electricity," you may need a simpler approach. High pressure steam equipment is complex and hazardous. A stirling engine or solid state peltier junction generator might be more practical.

My 2c.

Douglas Alpenstock wrote:It's an interesting thought experiment.

I'm not clear on how you plan to distill the enthanol to a burnable concentration. That requires a heat source.

Somewhere in the system you will probably need a heat source for cooking as well.

Regarding "Use the heat to boil the water to steam and drive an alternator to get electricity," you may need a simpler approach. High pressure steam equipment is complex and hazardous. A stirling engine or solid state peltier junction generator might be more practical.

My 2c.

You are definitely right about steam being insanely hazardous.
As far as cooking is concerned, yes, it's simple to make large gas bladders out of plastic sheeting, or by upcycling an old inflatable santa or some such. Then you can use the methane when you want for cooking.
You are also probably right about thermoelectric, except that peltier generators are on the order of 10 dollars per watt. Not very economical;
So say you want a 1KW system, which is basically the minimum size useful off-grid 'house' system.
That means you need 45 of these, wired in some configuration under 25 volts for use with a solar CC: https://www.tegmart.com/thermoelectric-modules/22w-teg-module
If you buy 50 you get a volume discount and it comes to $2,564.50. For just the modules. Then you need bus bars, wiring, contact plates, CC, etc...
Totally doable. Alone about twice as expensive as a similar solar setup with batteries. However, this cost is much more reasonable if solar is not useful.
No idea what the lifetime is on peltier modules but it's hard to beat a 30-50 year life of a good panel.
I've never seen a sterling engine that can produce a KWH of work. Enlighten me...

And another problem with burning ethanol that hasn't been addressed yet is that the flame is over 3 thousand degrees F, almost 3 times hotter than wood burns. Needs some kind of thermal mass setup with a shutoff.

Agreed, if the goal is 1 kWh, solid state generators are too expensive.

Stirling engines predate internal combustion engines, and were used for running pumps etc.

https://en.wikipedia.org/wiki/Stirling_engine

I think the temperature of ethanol combustion will depend in part on its purity and the design of the burner. If there is any water, the burn temperature will be lower.

Having a bit of chemistry background, and also having experience fermenting ethanol, I'm aware of the challenges you would face.  One of the reasons ethanol production is viable in a place like Brazil is the fact that it's a tropical setting where is it easy to grow the easiest feedstock, sugarcane.  The key word here is "viable".  What you want is to produce a fuel using less fuel than what you are making.  That is the really tough part.

What I would suggest though is to go in a different direction, and look at bio-diesel rather than ethanol.  Growing crops and extracting oil from them is far easier than extracting sugars, fermenting them, and distilling them to a grade sufficient for engines.  There are oil screws designed to press oils from temperate crops like corn and soybeans, and the chemistry to convert oils to bio-diesel can be performed in something as simple as a 5 gallon plastic bucket.  I myself bought a diesel truck with the idea of eventually producing the fuel for it.  Another advantage of diesel compared to gasoline is that diesel is inherently more efficient then gasoline, and you get more energy out of a gallon of bio-diesel then gasoline, and far more than a gallon of fuel ethanol.

Douglas Alpenstock wrote:Hi Aaron. Welcome to Permies!

You make an interesting proposal. I would love to see something like this in operation.

To start, I would suggest thinking about what work you want to accomplish with the energy. Think about what the end goal is, and work back from that. Is it the best way to get the job done (aside from being a cool project)?

Assuming an ethanol-fired generator is a good fit, off the top of my head I can see two main challenges.

First, making and distilling ethanol to a level of purity that will run in an internal combustion engine. Basic distilling is simple enough. I wonder what's needed to get high concentrations?

Second, finding or modifying an engine to run on ethanol. I've heard that ethanol eats the fuel system seals on older engines. Also, there may be requirements for special additives, oil or other lubricants to replace those in gasoline (for example, special oil is required for propane fired engines). I can't speak to carburetor adjustments, other than noting that ethanol has less energy per volume of fuel.

I think this was done in Brazil and possibly Cuba maybe 40 years ago.

Phew, the more I look at the work to be done, the more I wonder if solar panels might be easier!

One nice thing about ethanol is that it does not deteriorate as gasoline and diesel fuel do. The downside is that if you store it in 55-gallon drums you must connect a ground rod to the drums because ethanol is shockable. Lightning can detonate them with a rather surprising blast. If you see them in pharmaceutical companies they are always bonded to ground.


Sincerely,

William McCormick

The problem with ethanol is that it has no anti-shock additives as gasoline has. So it creates two problems, it creates static electricity when handled without special precautions, and two if it is subjected to high voltage as a dielectric in a capacitor it will detonate as a blown capacitor does. Gasoline contains small trace amounts of radioactive substances that ionize the gasoline which makes it more of a conductor. Similar to the radioactive material in smoke detectors that ionize the air in the detector. When you see a spark when opening electrical switching points or doing lift ARC TIG welding you are witnessing a blown air capacitor or condenser.

Your home light switch is an air capacitor that charges and discharges 120 times a second to stop the flow of electricity. When the points break or open the air over such a short distance cannot stop the flow of electricity and the air capacitor blows creating a very hot plasma a miniature explosion. This can happen with ethanol. Only electricity stops electricity. In an insulator, one particle holds off two particles, and two hold off four, and so on. That is how insulators or dielectrics work, they do not at first guard against the flow of electricity, only when they are charged in a ramping voltage through their thickness do they stop the flow of electricity. The dielectric and ARC are what kill most people.

Sincerely,

William McCormick