From Sugar To Ethanol Fuel With A Little Microbial Help

June 30, 2026 by Maya Posch 65 Comments

In these trying times it seems appropriate to work through some ‘what if ‘ scenarios, such as the local gas station suddenly not having any more gasoline to sell you, or said gas station ceasing to exist altogether. In that case it can be incredibly useful to be able to create your own gasoline alternative in the form of ethanol. As demonstrated by [Hyperspace Pirate] in a recent video this process is fairly straightforward once you have procured an appropriate feedstock, such as here sugar (sucrose).

Although baker’s yeast (Saccaromyces cerevisiae) is more commonly associated with the production of ethanol-laced drinks, there’s nothing that says that you cannot distill out the approximately 10-15% ethanol that results from a yeast feeding frenzy and resulting waste products.

How to do this distillation step is explained in the video, with the mixture heated and put through a self-made reflux column to deal with the fact that the water/ethanol mixture is an azeotropic mixture, meaning that a lot of water is expected to make its way out of the condenser along with ethanol without this measure to condense as much of the water vapor before it can make its way to the top of the column.

Ultimately the conversion rate of plain white sugar to ethanol is about 54%, with the rest turning into CO₂. With an appropriately converted combustion engine for running on 100% ethanol, it runs pretty well, though the final cost per liter of ethanol will heavily depend on your feedstock.

With the full costs of the electric heater of the distillation column taken into account – at 2.57 kWh/L – as well as the cost of the off-the-shelf sugar, [Hyperspace Pirate] with his Florida kWh cost of $0.12 paid around $2.62/L, or $9.91 per gallon. Even with how much prices at the gas pump have shot up recently, you’d pretty much need to find a free source of feedstock and otherwise optimize the process for it to make much sense, even in this economy.

That said, it’s crazy that the world of Mad Max doesn’t run on ethanol. If tomorrow a certain bubble were to implode and the global economy fell apart as a result, producing bioethanol would seem to be a highly marketable skill.

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Big Chemistry: Fuel Ethanol

May 21, 2025 by Dan Maloney 73 Comments

If legend is to be believed, three disparate social forces in early 20th-century America – the temperance movement, the rise of car culture, and the Scots-Irish culture of the South – collided with unexpected results. The temperance movement managed to get Prohibition written into the Constitution, which rankled the rebellious spirit of the descendants of the Scots-Irish who settled the South. In response, some of them took to the backwoods with stills and sacks of corn, creating moonshine by the barrel for personal use and profit. And to avoid the consequences of this, they used their mechanical ingenuity to modify their Fords, Chevrolets, and Dodges to provide the speed needed to outrun the law.

Though that story may be somewhat apocryphal, at least one of those threads is still woven into the American story. The moonshiner’s hotrod morphed into NASCAR, one of the nation’s most-watched spectator sports, and informed much of the car culture of the 20th century in general. Unfortunately, that led in part to our current fossil fuel predicament and its attendant environmental consequences, which are now being addressed by replacing at least some of the gasoline we burn with the same “white lightning” those old moonshiners made. The cost-benefit analysis of ethanol as a fuel is open to debate, as is the wisdom of using food for motor fuel, but one thing’s for sure: turning corn into ethanol in industrially useful quantities isn’t easy, and it requires some Big Chemistry to get it done.
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Homebrew Gel Fuel Keeps The Steam Coming, Legally

December 20, 2023 by Dan Maloney 31 Comments

All it takes is one knucklehead to go and do something stupid to screw things up for everyone. We’re not exactly sure who the knucklehead is behind the recent ban on hexamine fuel tablets, but given that it’s now proscribed in the UK under the “Control of Poisons and Explosives Precursors Regulations 2023,” we expect that that story is a doozy.

So what’s hexamine, and why should we care if it’s banned? As [Markus Bindhammer] explains, hexamine is a solid fuel commonly used to power model steam engines, among myriad other uses. Its ban leaves a bit of a hole in the model steam community, which [Markus] seeks to fill with this quick and easy gel fuel chemistry project.

The “California Snowball” is a homebrew version of what’s in those solid fuel cans you see heating chafing pans at catered events, with one common brand being Sterno. [Markus] used a saturated solution of calcium acetate (6 g in 50 ml of water) and added that to 150 ml of ethanol; commercial formulations usually use methanol to prevent anyone from drinking the stuff, with varying degrees of success. The calcium acetate forms a gel that looks like whipped cream and traps the ethanol inside. The gel can be easily scooped up and spread around, and burns with a clean, smokeless flame.

It may not exactly be a “plug and play” replacement for hexamine tablets, but one does what one can. And if there’s one thing we can celebrate about model steam engineers, it’s their persistence. We got a bunch of them together last year for a Hack Chat with [Quinn Dunki], and their passion for making things move with steam was pretty impressive.

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Wipe On, Wipe Off: Make Your Own Rain Repellent

January 9, 2023 by Kristina Panos 55 Comments

Once upon a time, we drove an old six-volt VW Beetle. One sad day, the wiper motor went out, and as this happened before the Internet heyday, there were no readily-available parts around that we were aware of. After briefly considering rubbing a potato on the windshield as prescribed by the old wives’ tale, we were quite grateful for the invention of Rain-X — a water-repelling chemical treatment for car windshields.

Boy would we have loved to know how to make it ourselves from readily-available chemicals. As you’ll see in the video below, it doesn’t take much more than dimethicone, sulfuric acid, and a cocktail of alcohols. [Terry] starts with dimethicone, which he activates with a healthy dose of concentrated sulfuric acid, done under the safety of an exhaust hood. After about 20 minutes on the stir mix-a-lot plate, [Terry] added ethanol and isopropyl alcohols. Finally, it was off to the garage with the mixture in a spray bottle.

After meticulously cleaning the windshield, [Terry] applied the solution in small areas and rubbed it in with a towel to create a thin bond between it and the glass. This creates a perfectly normal haze, which can be removed after a bit with a clean towel.

If you just love listening to your windshield wipers, at least make them move to a beat.

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the full charger with gas tank and engine

Charge Your Apple With Apples

April 19, 2022 by Matthew Carlson 16 Comments

When you think of ethanol, you might think of it as a type of alcohol, not alcohol itself. However, in reality, it is the primary ingredient in adult beverages. Which means humans have gotten quite good at making it, as we’ve been doing for a long time. With this in mind, [Sam Barker] decided to make ethanol out of apples to power a small engine to charge his phone.

The steps for making pure ethanol is quite similar to making alcoholic cider. A friend of [Sam’s] had an orchard and a surplus of apples, so [Sam] boiled them down and stored the mush in jugs. He added activated dry yeast to start the fermentation process. A dry lock allowed the CO2 gas that was being created to escape. Over a few weeks, the yeast converted all the sugar into ethanol and gas. In the meantime, [Sam] sourced a chainsaw and adapted the engine to run on ethanol, as ethanol needs to run richer than gasoline. The video below the break tells the story.

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Will A Kettle Filled With Alcohol Boil Dry?

February 1, 2022 by Zoe Skyforest 31 Comments

The average home kettle is set up to switch off automatically when water reaches its boiling point. But would a kettle filled with alcohol, which has a significantly lower boiling point, actually turn off? [Steve Mould] set out to find out.

The prediction was that a kettle full of 40% strength vodka would boil dry, as the vodka would evaporate before it actually got to a hot enough temperature to cause the kettle’s cutout mechanism to kick in. The experiment was done outside to minimise the dangers from the ethanol vapor. As it turns out, the vapor from the boiling vodka is about 80% ethanol and just 20% water, so eventually the mixture left in the kettle is mostly water and it boils hot enough to trigger the cutout mechanism.

However, the experiment doesn’t end there. Trying again with 99% ethanol, when the fluid started boiling, the kettle switched off even more quickly. So what’s going on?

The kettle in question uses a bimetallic strip, which trips the switch off in the base of the kettle when it gets too hot. There’s also a tube inside the kettle that carries vapor from the internal cavity and lets it pass over the bimetallic strip. When the liquid inside the kettle boils, it forces hot vapor through the tube, out of the kettle and over the bimetallic strip.

This strip triggers at a temperature significantly lower than the boiling point of water; indeed, as long as the liquid in the kettle is fairly hot and is boiling enough to force vapor out the tube, the kettle will switch off. [Steve] points out that it’s a good mechanism, as this mechanism allows the kettle to respond to boiling itself, rather than the arbitrary 100 C point which water technically only boils at when one is at sea level.

It’s an interesting look at a safety system baked into something many of us use every day without even thinking. It’s not the first time we’ve seen [Steve] dive deep into the world of tea-making apparatus, either. Video after the break.

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How To Get Into Cars: E85 Fuel

December 23, 2021 by Zoe Skyforest 33 Comments

If you’ve spent any time around the modified car scene in the last few years, you’ve probably heard about E85. Maybe you’ve even noticed a sweet smell emanating from the pitlane, or heard people cracking jokes about “corn juice.”

The blended fuel, which combines alcohol and traditional gasoline, can have significant performance benefits if used properly. Today, we’ll explore what those are, and how you can set your ride up to run on E85.

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