How do I make ethanol from sugar

Making ethanol at home ...

Funny, I found this on the Swedish Auto, Motor, Sport page:

Ethanol production at home:

For biodiesel:

For those who already have everything ...

Is it worth it? If I got that right (with the ethanol part) you need sugar and yeast (or alcohol) as raw materials, and then you can make 35 gallons of E100 per week - if you use alcohol, 70 gallons.

But the thing draws 3 kWh of electricity per gallon.

If this has been posted anywhere before, close Fred. But didn't find it.

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that is the question of whether the tax office allows it to pass as fuel if it is not anhydrous.

a crazy idea in my eyes.

if you are not a farmer with a large refractory barn, ample capacity for self-cultivation of wheat or the like and have secret neighbors, an annoying subsidy business.

And even then, I'd rather grow rapeseed forn ollen diesel. it is pressed and good .;)

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It is not worth it!

The sugar and the yeast alone blow everything up.

And then it is damn difficult to produce at least 96% alcohol.

I once calculated that the liter would be around 3-4 euros.

I am also currently looking for information on the subject and so make up my mind about it.

We have a farm and currently need for about 3000 € diesel per week.

Large rooms would be available for such a project.

Let's see what information can still be obtained.


Originally written by Papstpower

It is not worth it!

The sugar and the yeast alone blow everything up.

And then it is damn difficult to produce at least 96% alcohol.

I once calculated that the liter would be around 3-4 euros.

Hmm, I did the math just for fun and come up with something else.


- 35 gallons per week is about 130 liters of ethanol.

- 50 pounds of raw material are the basis for this 130 l - the supplier sells the "finished mixture" for 12 € (industrial sugar, yeast, anything else).

- The device costs € 8,000 and should last 10-15 years (let's say 10).

- To produce 130l of ethanol, I need about 1 kWh per liter.

A weekly production of 130l costs me:

12 € (raw material) + 16 € hardware (10 years x 50 weeks) + 39 € electricity (1 kWh - 0.30 €) = 67 €: 51.5ct per liter of ethanol.

(When it comes to hardware, I leave out depreciation and interest on capital).

If I want to mix E85 out of it, I need 15% fuel per liter of ethanol.

At 1.60 € fuel price means + 24ct.

Makes for home-made E85: 75.5 ct.

At least based on the manufacturer's information ...

Question is what the "raw material" is. If you use yeast, it needs food.

For 30L about 6-8KG sugar.


You can get about 1/4 to 1/5 alcohol out of the mash. So you would have to produce at least 520L of mash and distill it. In addition, the mash needs 10-14 days to ferment. So you always have 1000-1500L somewhere.


May be. I don't want to gloss over myself either, I've only calculated here purely on the basis of the manufacturer's information.

@ Golf F&I Gti: You're right. I have to add 15% petrol to the 130l E100. This means that I can turn the 130l E100 into just under 150l E85 by adding 15% petrol.

That means: 130l E100 at 67 € + 20l petrol at 32 € gives 150l E85 at 99 €, so the liter E85 costs only 66ct at home.

As I said, everything based on the manufacturer's information, whether they are correct, is an open question.

The raw material requirement of 12 euros for 130 l of ethanol seems far too low to me. You would need 400 - 500 kg of grain or a good 150 kg of pure sugar for 130 liters of pure alcohol.


Originally written by Golf F&I Gti

I don't know if the calculation is correct, but you only need 85% ethanol and not 100;)

Um ... if you distill mash to 85% ethanol, you have 15% WATER in it.

E85 is about 85% ethanol + 15% PETROL.

Do you recognize your mistake in thinking ?;)

LG Anja

I did the math using price assumptions:

Sugar Z (C12H22O11) € 0.60 / kg

1mol C12H22O11 ---- fermentation ----> 4mol C2H5OH (ethanol E)

C12H22O11: 342.3 g / mol => 2.92 mol / kg

C2H5OH: 46.07 g / mol

Density of ethanol = 0.79 kg / l

=> 4 * 2.92 mol ethanol / kg sugar

=> 11.69 mol E / kg Z

=> 0.5384 kg E / kg Z

=> 0.68 l U / kg Z

0.60 € / kgZ / 0.68 l E / kg Z => 0.88 € / l E

Here the price for yeast and nutrient salt was neglected and the energy expenditure for the distillation was neglected.

The latter can be realized by using an air conditioning system as a heat pump, so that only about a third of the heat capacity and the enthalpy of vaporization are used electrically. The rest is done by heat transfer from the condenser to the evaporator.

For ethanol you need 40.5 kJ / mol for evaporation, but first it is heated from 20 ° C to 78 ° C (dT = 58K) at 2.43 kJ / kg * K. Assuming a 15% fermentation product, about 4.5 kg of water are heated at 4.2 kJ / kg * K.

That results in 1096kJ for the water and 111.3kJ + 694.6kJ = 805.9kJ. Together about 1900kJ per liter of ethanol. This corresponds to 0.53 kWh and at € 0.20 / kWh € 0.11. A third of this is just under € 0.04 per liter of ethanol.

Pumps and stirrers can be neglected.

With cyclohexane you can get far above the usual 94% ethanol and thus bring less water into the engine. Maybe that's important.

Regardless of the technical complexity, I therefore consider it realistic to produce ethanol for € 1 / l.

As a notorious tinkerer and mechanical engineer, I assume that I can build such a system for 1000 € in material costs, largely from old parts.

That only pays for itself after several thousand liters. Nevertheless, I would find such a project very attractive. Just to have done it once.

It becomes significantly cheaper if you make E from wheat. A ton only costs a third of sugar.

Unfortunately, it doesn't make the process any easier. You have to grind and ferment beforehand in order to split the starch into sugar.

Well, there is still a little research missing.

With the equipment that has grown in this way, the garage is then half full ...

ALSO: Who does it !?

... I also help with the construction ...

Interesting contributions and ideas.

In operation, 33% additional consumption must be taken into account, which will further increase the costs per 100 km.

For the time being, that doesn't matter for the production costs. Have you dug up a corpse and where do you get the exact percentage from?