Environment

Audi just created diesel fuel from air and water

Audi just created diesel fuel ...
The first diesel made from air and water (Photo: Audi)
The first diesel made from air and water (Photo: Audi)
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An overview of the production process (Image: Audi)
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An overview of the production process (Image: Audi)
Adding the first batch of e-diesel to an Audi A8 (Photo: Audi)
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Adding the first batch of e-diesel to an Audi A8 (Photo: Audi)
The first diesel made from air and water (Photo: Audi)
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The first diesel made from air and water (Photo: Audi)
The Dresden pilot plant (Photo: Sunfire)
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The Dresden pilot plant (Photo: Sunfire)
One of the first batches of e-diesel (Photo: Sunfire)
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One of the first batches of e-diesel (Photo: Sunfire)
The Dresden pilot plant (Photo: Sunfire)
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The Dresden pilot plant (Photo: Sunfire)
The Dresden pilot plant (Photo: Sunfire)
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The Dresden pilot plant (Photo: Sunfire)

Audi is making a new fuel for internal combustion engines that has the potential to make a big dent when it comes to climate change – that's because the synthetic diesel is made from just water and carbon dioxide.

The company's pilot plant, which is operated by German startup Sunfire in Dresden, produced its first batches of the "e-diesel" this month. German Federal Minister of Education and Research Johanna Wanka put a few liters of the fuel in her work car, an Audi A8, to commemorate the accomplishment.

The base fuel is referred to as "blue crude," and begins by taking electricity from renewable sources like wind, solar or hydropower and using it to produce hydrogen from water via reversible electrolysis. The hydrogen is then mixed with CO2 that has been converted into CO in two chemical processes and the resulting reactions produce a liquid made from long-chain hydrocarbons – this is blue crude, which is then refined to create the end product, the synthetic e-diesel.

Audi says that the carbon dioxide used in the process is currently supplied by a biogas facility but, further adding to the green impacts of the process, some of the CO2 is captured directly from the ambient air, taking the greenhouse gas out of the atmosphere.

Sunfire claims that analysis shows the properties of the synthetic diesel are superior to fossil fuel, and that its lack of sulphur and fossil-based oil makes it more environmentally friendly. The overall energy efficiency of the fuel creation process using renewable power is around 70 percent, according to Audi.

"The engine runs quieter and fewer pollutants are being created," says Sunfire CTO Christian von Olshausen.

The fuel can be combined with conventional diesel fuel, as is often done with biodiesel fuels already.

The Dresden pilot plant is set to produce about 42 gallons (160 l) of synthetic diesel per day in the coming months, and the two companies say the next step is to build a bigger plant.

"If we get the first sales order, we will be ready to commercialize our technology," von Olshausen says.

Sunfire anticipates that the market price for the synthetic diesel could be between 1 and 1.5 Euros per liter, which would be nearly competitive or a little more expensive than current diesel prices in Europe, but the actual figure will be largely dependent on the price of electricity.

For an overview of the production process, check out the promotional video below.

Sources: Audi, Sunfire

sunfire: Alternative fuels from air, water an renewable energy

40 comments
John Banister
Rather than capture CO2 out of the atmosphere where the concentration is very low, why not work with someone like Schwarze Pumpe who captures power plant CO2 before it is released into the atmosphere. Then, they can close the cycle, using captured CO2 from hydrocarbon consumption directly for hydrocarbon creation.
Racqia Dvorak
Thorium Nuclear power plants plus this and Algae-Based Bio-diesel? Sometimes it seems like no one out there in power cares about the future or even about truly changing the world.
Joel Detrow
That's pretty impressive! This means we can continue using diesel where electric doesn't make sense, but in a way which is carbon-neutral, leaving sequestered carbon right where it is.
Bob64
I believe that converting electricity to liquid fuel is going to be the future of transport energy supply. Liquid fuels have a lot of advantages over batteries, including high energy density, ease of transport and quick refueling. Planes are going to need liquid fuels, batteries are just too heavy. Once solar/wind become the main source of energy, I believe that electricity prices will drop. Very cheap energy is the next big step forwards for the world economy. Many things that are currently too expensive because of energy costs will become viable, leading to massive changes. The next big economic revolution, the "energy revolution" is just around the corner.
mhpr262
@John Banister: They are indeed using CO2 that is the exhaust of some power or manufacturing plant nearby that would otherwise have gone into the atmosphere.
Slowburn
The engine runs quieter. I call bullcookie on that. The improvement in efficiency is appreciated but I doubt is cost competitive with even synthetic oil.
Pat Pending
"....by taking electricity from renewable sources like wind, solar or hydropower and using it to produce hydrogen from water via reversible electrolysis." Am I missing something here? Why not liquefy the Hydrogen using the above energy sources and run gas engines directly on it? Exhaust product = water.
Mike Giles
How much will it cost t the pump?
Captain Obvious
The US Navy did the same. It's expensive, because it uses a lot of electricity, essentially storing it as chemical fuel. Then you have the inefficiency of the engine that burns it. It's faster to refuel than charging a battery, though.
Делян Ангелов
>>Why not liquefy the Hydrogen using the above energy sources and run gas engines directly on it? Hydrogen is very inconvenient for storage or transportation, since it leaks very easily (the hydrogen molecules are very small), it is odorless so leaks will not be detected early enough, and it makes highly combustible, even explosive fuel-air mixtures ... Fore more, see: http://en.wikipedia.org/wiki/Hydrogen_safety