Solar Powered Ethanol Project Help

[axident_prone2004]

I am part of a College Engineering Design Class creating a solar powered Ethanol Distillery. The system will be computer automated and powered by a solar pannel array with battery storage. The sysem is designed to create enough ethanol to run one households cars or at least help out. (so were gonna start off aiming for 10 gallons a week).

The team is 2 Mechanical Engineers and 2 Computer Science Engineers. I have a general understanding of distillation from my dad ( who used to run a whiskey still on the ranch back in the day). We could use a lot of information from you guys... If any of you could answer any of the following questions we would greatly appreciate it.

1. Has anyone tried this before?

2. DC heater info.. Have any of you had luck with any DC heaters for this type of scale? or should we convert to 120 v ac?

3. What is the most energy efficient variation of an alcohol distillery ( there are so many designs out there...which column setup or condensor designs are most efficient)

4. The system will have temperature sensor that provide feedback to a control system to control the temperature in the Mash tank for optimal fermentation, and when boiling to maximize alcohol content.

5. Any other information on systems you have used that worked well


The purpose of this project is to use "free" energy to help with the horribly inefficient process of creating alcohol. Thanks.

[HookLine]

1. Has anyone tried this before?

Almost certainly. But I do not know who.

2. DC heater info.. Have any of you had luck with any DC heaters for this type of scale? or should we convert to 120 v ac?

If your power source is solar electric panels (ie DC), then you would be better off using DC heaters for efficiency, if you can get them. Converting from DC to AC will be quite inefficient.

Using solar as a heat source via steam, might be better.

3. What is the most energy efficient variation of an alcohol distillery ( there are so many designs out there...which column setup or condensor designs are most efficient)

Don't know, but the Bokabob slanted plate or the vapour management are the most popular reflux designs here. Pretty unlikely you will find a more energy efficient design for a small, easy to make still.

4. The system will have temperature sensor that provide feedback to a control system to control the temperature in the Mash tank for optimal fermentation, and when boiling to maximize alcohol content.

Boiling/vapour temp is determined by the composition of the wash (proportions of alcohol and water). You do not control it directly. If you try to you will just end up chasing your tail.

The purpose of this project is to use "free" energy to help with the horribly inefficient process of creating alcohol. Thanks.

You probably already know, but there is no such thing as 'free' energy.

Have fun.

[eternalfrost]

-you deffinly want a reflux still (opposed to your dads whisky style) to get the purity needed for fuel

-ive done some work with solar generation. photovoltaics are actually horribly inefficient. they are mostly used because they can easily be installed at the point-of-use. however, they are hardly ever used for large scale power plants. for those the most efficient concentrate the light and use it to generate steam for turbines, or use the heat to power Stirling engines.




i would say just cut out the electricity all together, you dont need it. you are after HEAT which the sun has plenty of. the only reason to use electric is if you want to distill on a not-so-sunny day. then you also need some sort of battery system to remain self-contained, and you would need quite a beastly battery system to store enough juice for 10 gallon product capacity!

i would say a parabolic (or an array of flats approximating parabolic) with the boiler at the focus. of course you want the heated surface black etc.

also, insulation is key here, insulate the boiler and column as much as you can so your not wasting any of that heat

[rad14701]

Before you go much further you need to do some research first... If your goal is 10 gallons per week then you need to calculate how many BTU's it will take to distill this amount... Then you work from there as far as required scale and design characteristics... Some for the required calculations are available on the parent site if you don't already have a resource...

[seravitae]

solar concentration is the best way to get energy.

one way to save a relative crapload of energy is to seperate the ethanol from the water in a biphasic system, where the secondary ethanol soluble phase has favourable chemical properties (non-azeotropic but miscible with ethanol). You can then seperate the ethanol with one phase and liberate it.

The heat source is the easy bit... simple heat controller.. triacs or relays depending on load size. sorry guys.. i dont mean to rain on your parade but 99% of this project is chemical engineering, ie. selection of the right process conditions for selective extraction of ethanol. if you have time i'd suggest changing projects.. Probably not suitable (you may find it hard to demonstrate all the concepts you've learned you need to get good grades)...

[theholymackerel]

Instead of usin' solar power to provide electricity or heat to power a standard still, why not use a solar still.

They have been around along time.

Google "solar still".

[violentblue]

I wonder if one could build a solar still for stripping wash, a continuos still with the boiler heated by a parabolic mirror. of course one would have to figure out how to get it to track the sun, as well as come up with an explanation for the neighbours as to what that contraption on you roof is.

[seravitae]

it's possible, you can get over 1000w per square meter of infrared heat in australia.. aussies could easily make a solar still. but then you have a big shiny ass thing in your backyard attached to your illegal still, raising interest from nosy neighbors, etc.

[decoy]

Somthing ive been thinking about, there are some nice exisitng solar stills,
most if not all are more like pot stills, designed to output around 40%.

if you are looking at producing 10galons a week and your idea is to use it as fuel,
you can do a few things to enhance output but resulting in a product i would definatly NOT drink!

First i would use a good Turbo Yeast Recipie that will produce a high alcohol wine in the range of 20%.
this will produce higher levels of Methanol, and funky tastes.

i would scrap the solar pannel path as this will just increase costs when you can keep it simple with existing techniques.

i recently watched an eppisode of mythbusters were they made a large mirror focused to burn stuff at
a distance of i think 2M then a boat on watter.

anyway here is a sketch of what i have been thinking about trying one day..

Solar still idea

2008-09-25.jpg (35.65 KiB) Viewed 6715 times

this was taken from the mythbusters eppisode were they do the burning mirror chalange.
use a mirror 1000x500mm wide you make a frame to support the mirror across the top and bottom back
then place a bar accros the front middle of the mirror with bolts on both sides to pull the center of the mirror into rear frame
this will start forming a parabola, and adjusting how tight you do the nuts up will alterd the focal length.
moving the crossbars up or down on the top and bottom of the mirror towards its center will further alter the parabola curve.
once you have the correct parabola and focus point figured out, you can do 4 or more mirrors accross to increase heat energy.

i would then use 3 1" copper tubes brased together flat on top of each oteher for the entire width of the mirrors.
you will notice walls halfway accros the ends of the tube to keep a level of liquid in the tubes.
the center one i would use to feed the wash slowly as it travels accross alcohol vapor starts evaporating as its heated,
the vapor travels to the top tube and across to the reflux column.
the third tube on the bottom is to add more path to the wash to ensure you most if not all aclohol out of wash before it is dumped.

when compleet you spray bleech or peroxide onto the outside of the copper tube this will create a black oxide or dark brown oxide on the copper, to increase heat absorption from the sun, the techniqe is caled "Patina" to age copper.

i would use the copper tube as an axis to pivot the mirror up and down to track the sun for maximum efficancy

i would also mount the mirror and tube in a insulated box with a glass front to prevent wind cooling the tube and it would also make its own hot house.

adding salt to the wash will increase the boiling point of water a bit this will help make it more efficant increasing the alcohole % output.

you can use a solar panel or two to controll servo moters to track the sun, operate a pump to controll the wash input based on the output.

another thing that would increase output is to create a vacume in the still, this will lower the boiling point of alcohol and water, requiering less heat.
you dont need to create a perfect vacume, but eaven hal an atmosphere will give you dramatic improvment, there is a table on the parant site i think.

you can replace glass mirrors with polished stainless or perspex mirrors these will be easyer to create a parabola but with a reduction in efficancy.

now i belive this would make a nice pot type still to produce alcohol slowly but 10galons a week at 90% + hmmm, dont forget the output increasing mods i have sugested will make the final product a fuel not a drink..

DONT DRINK IT !!!!

cheers.

[axident_prone2004]

I completely agree with putting emphasis on thermal solar power not all on photovoltaics. A good vacuum radiant heat collector can boil water in antarctica. The project is more of an IDEAL plan and a learning experience. I understand the problems with coverting light into electricity and its inefficiency.

Your posts have been very helpful... Bottom line we are designing a system with an electric heater ran off solar panels and battery storage...I understand this takes an incredible amount of energy which would require a large solar panel array and considerable storage.Storing energy is one of the biggest problems we face today ..Using the sun to heat water is much more efficient and will probably be integrated somewhere along the way...

But for now if anyone would like to lead us to or draw some designs to start from that we could modify we would appreciate it...I'm looking for a tried and true design that uses an electric heater and can make fuel grade ethanol on an accetable scale without reinventing the wheel.( but dont want to steal anyones ideas or use someone else to do the project). thanks

[axident_prone2004]

And to help DECOY out. Sometimes when trying to harness light energy its better to use a liquid like ethylene glycol( some antifreeze) to capture heat energy then use a heat exchanger to heat you mash..Helps with contamination and you can store heat energy with a well insulated container and apply heat whenever needed.

[decoy]

Project or not i dont know why you would use solar panels to do the job of somthing that is proven to be more efficiant without them,
solar panels are quiet simple you buy a lot of em and a heater, you can use any heating element with them as long as you dont go over the voltage rating and you need to provide more current then the element draws.
wire you solar panels in a series to achiev the desired voltage, then keep adding the same amount of solar panels in parallel to provide more current then what is requierd by heating elements..

this is an example, you will need to do calculations as requierd by equipment you have.
Element is 110V and draws 12A
solar panel = 12V 4A

you will need to connect 10x solar panels in series to deliver 120V at 4A
now you need 4 of the above "10 solar panels wierd in series" to be wierd in parallel to deliver 120V at 16A
thats a total of 40 Solar panels, to make the unit run reliably.
in Australia a 12V 4A solar panel costs approx $300 x40 thats $12000.00
keep in mind if it is an overcast day or one of the panel cells are shadowed by somthing you will loose current and or voltage.
now i havent included solar panel regualtors etc, and maybee battery banks when you get moving patchy cloud cover etc..

but...If you still want to use solar to boil liquid, look into "Peltier" thermoelectric devices.

if you dont know what one is, its a transistor pack sandwiched in aluminum, when you apply a current to the device it will draw heat energy from one side and radiate it on the other, there used in lots of small car fridges and warmers.

you could use them to move heat from the condenser coils to your boiler. this could help you utelise energy a bit more..

alternativly the use of a refrigeration compressor to heat water is nothing new.. you would draw the heat from your condensor and return it back into your boiler, supplementing some heat from a heating element..

[al_shine]

With two mechanical engineers and two computer scientists you'd think you could create a motorized parabolic solar oven that knew what time of year it was and where the sun was and where the black pot is.

Parabolic reflectors are the fastest heating designs in the solar oven world. 2kW per square meter is hard to beat.

The amount of energy it takes to make a solar panel would make your project ineffective even if you got it working.

I know how it is with school projects at times, but servo control to get a reflectorized umbrella to hit a big black pot isn't that hard, and you're not doing anything on cloudy days anyway. Be better off with a an autoloading pot (another relatively simple industrial control) that waited for the sun to shine.

As my EE father tells me, "If you do it right, instead of a demonstration project you get a friend for life."

[minime]

Can't remember where I saw it but one of the simplest solar devices I've seen for PRIMARY distillation was a tilt frame where the wash feed was to the top of the frame into a terry cloth material with a sheet of glass about 4 inches above it. As the wash slowly travels down the terrycloth it evaporates but re-condenses on the glass and is collected on the bottom of the glass as it runs down. Was bringing the proof up to 60% for free and can be scaled to any size if space permits. I think on a good day you could process a hell of a lot of wash to 60% and that's where most of our energy is consumed. Just a thought..........

[decoy]

I love trying stuff, and i belive people should experiment but somtimes its very obvious that this one is going to blow the budget bigtime for what it acives..

the key requierment is to run a car, if you are going to mix 10 or 20% to fuel then you can get away with 60% abv which would degrade your performance..
i look at it that you would target 60% + to fuel ratio, and if it was an alternative energy project id be targeting 100% ethanol at 95%abv

to achive this you ned to produce 5 Litres of 95% ABV daily, with about 6 hrs avrg of workable daylight.

it is posible to achive this, there is nothing new about it and there is nothing to proove, i just dont belive its the way to go with solar panels cost wise when there are clearly other, Prooven, alterneatives that are cost efective.

if you want to do a project, i would be looking at developing a cost efective technique to concentrate as much solar energy onto a target as comented by al_shine.

With two mechanical engineers and two computer scientists you'd think you could create a motorized parabolic solar oven that knew what time of year it was and where the sun was and where the black pot is.Parabolic reflectors are the fastest heating designs in the solar oven world. 2kW per square meter is hard to beat.The amount of energy it takes to make a solar panel would make your project ineffective even if you got it working.

[I-GOR]

Parabolic reflectors are the fastest heating designs in the solar oven world. 2kW per square meter is hard to beat.

The amount of energy it takes to make a solar panel would make your project ineffective even if you got it working.

Resistance electric heating sucks - it's about the most ineffecient way to use energy. What decoy sketched above is called a parabolic solar trough. My brother and I dinked around with designing a solar trough vapor engine to run power a rotary engine generator. (he's more technically proffecient than I am - the tricky part was selecting the medium.) Didn't have the time to see it all the way through. I know there's a company that installs highly polished solar troughs with salt brine running through them on top of roofs as a heating system and possibly for power generation - way more efficient than either p.v. or flat panel.

Of course, they have tracking devices. Decoy's got it pretty much figured out. Get somebody on your design team who's good with servos to research existing tracking systems. The tracking system itself could run on a small p.v. panel. Also, look into solar desalinizing systems - slow, but efficient.

[al_shine]

Yeah, the trough design is awesome, especially if you can use that much.

For more personal sized projects, I was thinking more along the lines of



that keeps itself pointed at the sun, with a large pot.

For hands on distilling you could just keep an eye on where it is pointing, because you are anyway to take your cuts 'n' stuff.

[DamonPatton]

I am part of a College Engineering Design Class creating solar panels powered Ethanol Distillery. The system will be computer automated and powered by a solar pannel array with battery storage. The sysem is designed to create enough ethanol to run one households cars or at least help out. (so were gonna start off aiming for 10 gallons a week).

The team is 2 Mechanical Engineers and 2 Computer Science Engineers. I have a general understanding of distillation from my dad ( who used to run a whiskey still on the ranch back in the day). We could use a lot of information from you guys... If any of you could answer any of the following questions we would greatly appreciate it.

1. Has anyone tried this before?

2. DC heater info.. Have any of you had luck with any DC heaters for this type of scale? or should we convert to 120 v ac?

3. What is the most energy efficient variation of an alcohol distillery ( there are so many designs out there...which column setup or condensor designs are most efficient)

4. The system will have temperature sensor that provide feedback to a control system to control the temperature in the Mash tank for optimal fermentation, and when boiling to maximize alcohol content.

5. Any other information on systems you have used that worked well


The purpose of this project is to use "free" energy to help with the horribly inefficient process of creating alcohol. Thanks.

Hello friend I know thread is pretty old but were you able complete the project? It seems exciting one to me and I would love to work on it..Share some details.

[Bushman]

I am part of a College Engineering Design Class creating a solar powered Ethanol Distillery. The system will be computer automated and powered by a solar pannel array with battery storage. The sysem is designed to create enough ethanol to run one households cars or at least help out. (so were gonna start off aiming for 10 gallons a week).

The team is 2 Mechanical Engineers and 2 Computer Science Engineers. I have a general understanding of distillation from my dad ( who used to run a whiskey still on the ranch back in the day). We could use a lot of information from you guys... If any of you could answer any of the following questions we would greatly appreciate it.

1. Has anyone tried this before?

2. DC heater info.. Have any of you had luck with any DC heaters for this type of scale? or should we convert to 120 v ac?

3. What is the most energy efficient variation of an alcohol distillery ( there are so many designs out there...which column setup or condensor designs are most efficient)

4. The system will have temperature sensor that provide feedback to a control system to control the temperature in the Mash tank for optimal fermentation, and when boiling to maximize alcohol content.

5. Any other information on systems you have used that worked well


The purpose of this project is to use "free" energy to help with the horribly inefficient process of creating alcohol. Thanks.

Hello friend I know thread is pretty old but were you able complete the project? It seems exciting one to me and I would love to work on it..Share some details.

The person your asking for information hasn't posted in years so I would not expect an answer!

[FullySilenced]

Heck Bushy we better hope they have graduated by this point....

or we can worry about anything they engineered...

FS

[arafatar]

Hi all,

Can anyone recommend a reasonably priced solar powered fan that I can buy in the UK which I can attach to me Stevensons screen?

Thank you!

[badflash]

There is a section on solar still is "Alcohol Can Be a Gas". Vacuum distillation can also be used to lower the vaporization temperature. Couple the vacuum pump so it pressurizes the discharge to the condenser and use that to pre-heat the incoming wort.

[Pikey]

Trouble with reflux stills is all that wasted heat !

Interesting nobody suggested the pot still and preheater ala Chanteraise for a first run, then a pot with thumper for the "spirit run" - ie use all the heat twice instead of all that wasted cooling in reflux. I'm just wondering whether you could use the output from the thumper to preheat the charge and thus use the heat nearly 3 times !

[badflash]

If you run the car on Just alcohol, you only need 165 Proof. The only reason for the 98% pure alcohol is to make it mix with the denaturing product.

[Pikey]

If you run the car on Just alcohol, you only need 165 Proof. The only reason for the 98% pure alcohol is to make it mix with the denaturing product.

I didn't know that

[The Baker]

Trouble with reflux stills is all that wasted heat !

Interesting nobody suggested the pot still and pre-heater a la Chanteraise for a first run, then a pot with thumper for the "spirit run" - i.e. use all the heat twice instead of all that wasted cooling in reflux. I'm just wondering whether you could use the output from the thumper to preheat the charge and thus use the heat nearly 3 times !

I would certainly try a pre-heater after the thumper, why not?

I think one of the traditional brandy stills, an Armagnac still, (google The "Armagnacais" still, or Armagnac Still) is interesting.
The cool wine cools the worm in the condenser and from then on it gets just a bit more technical, it is fed, warmed, from the top of the (enclosed) condenser into the next-to-top plate of a sort of plate still.

Far from beyond the skills of some of our members to build and experiment with.

Geoff |

P.S. If the still is gas, put a shield around, if electric make it a nice jacket. LOTS of heat is lost around the outside. G.

[neevamerk]

It is very helpful information for my project. Thank you for sharing