Synthetic options for the diesel engine

Synthetic options for the diesel engine
Professor Christian Beidl with the world’s first oxymethylene ether powered research vehicle. Credit: Katrin Binner

Synthetic fuels, such as oxymethylene ether, could prepare Diesel vehicles to play a major role in the drive train mix of tomorrow. Scientists at the TU Darmstadt are carrying out research into the practical viability of alternative fuels.

Professor Christian Beidl, Head of the Institute for Internal Combustion Engines and Powertrain Systems at the TU Darmstadt, does not consider the current debate on and electric motors as competing drive train systems to be particularly expedient. Instead, the expert favours an open contest between technologies, which considers the system as a whole, because, he believes, the Diesel will continue to play a crucial role in the drive scenarios of tomorrow – particularly in long-distance transport.

"It is not the engines as energy converters that are the problem", Beidl emphasises, "but rather the fuels". For many years, his team has been conducting research into new non-fossil-based fuels for Diesel engines, designed not only to reduce nitrogen oxide and particulate matter pollution levels, but also as a sustainable solution to the CO2 problem. The main challenge that this entails is to resolve a conflict that is typical for Diesel engines, namely that engines with a high degree of efficiency tend to generate high temperatures which, in turn, results in a high nitrogen oxide output. The established way to reduce temperature peaks within the combustion chambers is to include a return feed of virtually anoxic exhaust gases. However, the lower the oxygen levels, the more soot particles are formed there. "Therefore", Beidl explains, "to resolve this conundrum we need to inhibit the formation of soot." Experiments conducted on industrial drive system and car engines as well as on a single-cylinder research engine have already shown that the use of oxymethylene ether is the ideal way to achieve this objective. The researchers have performed basic experiments and carried out realistic driving simulations for various operating modes and driver profiles under differing environmental conditions, in the course of which they focused on emissions, process controls and various exhaust gas aftertreatment concepts. They have been able to demonstrate that oxymethylene ether enables soot-free combustion whilst increasing the efficiency level of the motor, but that it also reduces energy density due to its high oxygen content.

Outstanding Properties

Thus, the optimum adaptation of Diesel engines to this synthetic , according to Beidl, will require more in-depth research in combination with technological progress. However, the basic engine technology will not change. "We now know that oxymethylene ether fuels have some outstanding properties", says Beidl, who is also excited about the technical process chain involved in the production of the new fuel. As oxymethylene ether consists, among other things, of hydrogen, which can be synthesised from surplus electrical energy, one can imagine possible solutions which would both absorb peak loads and help to improve the distribution and storage of electricity from regenerative power sources.

In terms of introducing oxymethylene ether, Beidl currently imagines two possible scenarios. In one scenario, the oxymethylene ether would be deployed as a fuel supplement – comparable with ethanol – such that it would penetrate the entire market via existing infrastructure. Another scenario would involve its niche application in ships, locomotives and agricultural vehicles. However, for a long time to come, crude-oil-based fuels and their production is likely to remain significantly more cost effective than , which are currently only available at the laboratory scale. Yet, Beidl views attempts to resolve the CO2 issue by means of electric drive systems alone as short sighted: "We want to show that oxymethylene ether represents a socially relevant parallel development path."


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Jun 24, 2017
'Yet, Beidl views attempts to resolve the CO2 issue by means of electric drive systems alone as short sighted: "We want to show that oxymethylene ether represents a socially relevant parallel development path."

Yeah, if your university research is sponsored by the German car industry, of course replacing ICEs with EVs is "short sighted". Of course, if you're objective then it's synthetically extending the life of ICEs that still pollute with CO2 that's short sighted.

"It is difficult to get a man to understand something, when his salary depends on his not understanding it." - Upton Sinclair

Jun 25, 2017
Of course, if you're objective then it's synthetically extending the life of ICEs that still pollute with CO2 that's short sighted.


CO2 isn't a pollutant - you yourself are continuously emitting it. The issue is with net excess emissions that aren't recycled back. Complaining about engines emitting a perfectly harmless gas is a red herring.

The short-sightedness for drumming up electric cars is the infrastructure, which cannot cope with the demand for batteries for millions and millions of electric cars, and the amount of hazardous wastes created by scrapping the batteries, and the incredible cost of the whole system.

EVs are borderline manageable for small passenger vehicles and grocery getters; it's a complete pipe-dream to turn all road transportation over to batteries.

Jun 25, 2017
"It is difficult to get a man to understand something, when his salary depends on his not understanding it." - Upton Sinclair


People are eager to call a shill where they refuse to examine their own biases.

Jun 25, 2017
The main challenge that this entails is to resolve a conflict that is typical for Diesel engines, namely that engines with a high degree of efficiency tend to generate high temperatures which, in turn, results in a high nitrogen oxide output.


The true challenge is the regulatory environment, which is starting to look like a deliberate attempt to oust internal combustion engines.

Small ICEs are very much at the limit of efficiency, and the current regulations about fuel consumption and CO2 output have resulted in car manufacturers making smaller cars as well as cheating on every test - simply because they can no longer adhere to the demands without unreasonable compromises from the consumers' point of view.

The efficiency point is a red herring - relaxing the efficiency standards by couple percentage points would allow cleaner running engines. it doesn't matter if a car consumes 6 liters of fuel instead of 3 or 4, if the fuel itself is cheap, clean and renewable.

Jun 25, 2017
Eikka:
CO2 isn't a pollutant - you yourself are continuously emitting it.


Of course it is a pollutant. Tell me how it's harmless after you hold your breath long enough to post - if you survive.

And while of course humans exhalations are so tiny compared to car exhaust that nobody's saying we should eliminate them, we are talking about car exhaust not human exhalations. Except for the strawman you pushed, a favorite nonsensical fallacy of Greenhouse deniers.

Car exhaust is producing quite a lot of the CO2 that exceeds our planet's capacity to keep out of the Greenhouse and oceans. It is already driving species to extinction, and will include us in that mass extinction while people like you help ignore it.

But most importantly car exhaust is something we have control over eliminating. So we are. Because we want to survive.

Jun 25, 2017
Eikka:
The short-sightedness for drumming up electric cars is the infrastructure, which cannot cope with the demand for batteries for millions and millions of electric cars, and the amount of hazardous wastes created by scrapping the batteries, and the incredible cost of the whole system.

EVs are borderline manageable for small passenger vehicles and grocery getters; it's a complete pipe-dream to turn all road transportation over to batteries.


Except EVs replace the huge, filthy infrastructure of the oil/gasoline/diesel industry, and much of the vehicle maintenance industry's. Practically all of EV materials can be (and mostly already are) recycled.

Many car corps are already proving how EVs, their batteries and charging infrastructure are manageably rolled out. And that's even before achieving the kind of scale that ICEs have, at which point they're even more easily rolled out.

You usually have a lot better arguments, even when wrong, than these crude fallacies.

Jun 25, 2017
Of course it is a pollutant. Tell me how it's harmless after you hold your breath long enough to post - if you survive.


That's idiotic. By the same metric, water, or air humidity is a pollutant because you can't breathe plain H2O.

we are talking about car exhaust not human exhalations


Humans actually exhale more CO2 per kWh energy produced than automobiles, because our metabolism is less efficient than an engine. You're just making a completely artifical complaint - CO2 in the exhaust of cars is not a real problem except for the fact that it comes from fossil fuels.

Except EVs replace the huge, filthy infrastructure of the oil/gasoline/diesel industry


So would new synthetic renewable fuels.

Many car corps are already proving how EVs, their batteries and charging infrastructure are manageably rolled out


No they aren't. The whole industry has barely even started. You just don't understand the scale of the problem.

Jun 25, 2017
Car exhaust is producing quite a lot of the CO2 that exceeds our planet's capacity to keep out of the Greenhouse and oceans.


Guess how the synthetic fuels are made? By pulling CO2 out of the atmosphere. It's a zero sum - and that's the whole point.

Why? So the randomly variable output from renewable energy could be put to some meaningful use. It's necessary because we cannot build enough batteries, for cheap enough, to store all that energy - especially when trying to build electric cars at the same time.

This CO2 capture has to happen regardless of what you do with it, because a plain hydrogen economy is completely unwieldy - the surplus energy has to be stored into hydrocarbons so it can be effectively stockpiled for energy security and ease of transportation.

Therefore it makes only sense to use the hydrocarbons directly as vehicle fuels, instead of wasting money, resources, and energy into building electric cars.

Jun 25, 2017
Besides, the CO2 capture for carbon has to happen again for a different reason: the clothes on your back are made of oil, the medicines are synthesized from petrochemicals, 80% of the world food production runs on fertilizers derived out of fossil fuels. Think of a world without antibiotics, or even aspirin, because we can't go back to scraping it off of willow bark - we couldn't produce neary enough for 8 billion people.

You can't do away with the "filty oil industry" without completely destroying the lives of billions of people, so you have to substitute it with something else. That something is synthetic petrochemicals made out of hydrogen and CO2.

Jun 25, 2017
Eikka:
Of course it is a pollutant. Tell me how it's harmless after you hold your breath long enough to post - if you survive.


That's idiotic. By the same metric, water, or air humidity is a pollutant because you can't breathe plain H2O.


Air humidity doesn't pollute, because "pollute" means "contaminate with harmful or poisonous substances". Even at 100% humidity air is not polluted by water, because water is not harmful or poisonous when breathed, or when breath is held. CO2 is harmful and poisonous when breathed in concentrations easily exceeded when holding one's breath for more than a few minutes.

But indeed that is not the metric that makes CO2 an important pollutant, because humanity doesn't face a breath holding crisis. It's the CO2 polluting the atmosphere that makes the catastrophic Greenhouse and acidified oceans, harmful and poisonous.

It's your calling CO2 "harmless" that's truly idiotic.

Jun 25, 2017
Eikka:
we are talking about car exhaust not human exhalations


Humans actually exhale more CO2 per kWh energy produced than automobiles, because our metabolism is less efficient than an engine. You're just making a completely artifical complaint - CO2 in the exhaust of cars is not a real problem except for the fact that it comes from fossil fuels.


But human metabolism is more efficient in KWh per human activity than our automobiles, even for travel. It is indeed an "artificial complaint", as I said human exhalation isn't a meaningful problem, even though the same substance is a catastrophic problem in car emissions.

Not because it comes from fossil fuels. It is a problem because car emissions put far more CO2 into the Greenhouse than human exhalation does. More to the point, eliminating car emissions is part of the solution, because we can do that. While eliminating human exhalation is not part of any legitimate solution.

Jun 25, 2017
Eikka:
Except EVs replace the huge, filthy infrastructure of the oil/gasoline/diesel industry


So would new synthetic renewable fuels.


Yes, carbon-neutral renewable fuels, either from biomass or chemically storing energy generated by zero-carbon tech like wind/solar/etc would do so. They are part of the multiple replacements for our multiple obsolete energy systems. Along with EVs.

Jun 25, 2017
Eikka:
Many car corps are already proving how EVs, their batteries and charging infrastructure are manageably rolled out


No they aren't. The whole industry has barely even started. You just don't understand the scale of the problem.


Yes they are, and yes I do. So do industry researchers and their financiers:
https://about.bne...by-2040/

Jun 25, 2017
Eikka:
Car exhaust is producing quite a lot of the CO2 that exceeds our planet's capacity to keep out of the Greenhouse and oceans.


Guess how the synthetic fuels are made? By pulling CO2 out of the atmosphere. It's a zero sum - and that's the whole point.


Well of course carbon-neutral car exhaust is not a problem. Synthetic fuels made by renewable energy that don't worsen the Greenhouse are of course a welcome transformation from the filthy oil industry into a clean one. Indeed, the large amount of Greenhouse carbon that would be sequestered in the global petrofuel distribution and storage system would be an excellent sequester of a good amount of the carbon previously extracted from the ground.

I don't know why you'd think that I am against emissions themselves, though health hazards like asthma are also a problem - that I'm not concerned with here.What I'm against is the increasing Greenhouse and the catastrophic damage it's bringing down on us.

Jun 25, 2017
Yes they are, and yes I do. So do industry researchers and their financiers:


I find those researchers and experts lacking in their assumptions about the situation. They are looking at trends for battery prices etc. which cannot continue within any realistic scenario, and have fallen victim of the same general hype.

A single battery factory like the Tesla Gigafactory can produce 35 GWh of batteries a year, and supply 3-5 million electric cars. At that level they alone are consuming a sixth of the world lithium production. There are 250 million passenger vehicles in the US alone.

Then there's renewable energy, which requires Terawatt-hour scale energy storage. That is the elephant in the room, without which you cannot even get clean energy for the electric cars.

When you start racking up the numbers, we're a couple orders of magnitude short, and the timeframe given is years to couple decades to make a 1,000 fold increase in output. It just doesn't seem plausible.

Jun 25, 2017
I don't know why you'd think that I am against emissions themselves, though health hazards like asthma are also a problem


Because you talk like CO2 in itself is a problem, and only now backpedaled on the issue to say that carbon-neutral CO2 emissions aren't a problem.

The whole point of the article is that we could make fuels that emit none of the stuff that cause asthma and the rest. A clean burning synthetic fuel in an engine with proper emission controls - or a clean burner like a solid oxide fuel cell - will not make anything more than water vapor and CO2, and if these are a problem to you then you're a loony.


Jun 25, 2017
Consider for example, the global market for new cars approaches 78 million units this year, and the total number of cars exceeds 1 billion.

If 35% of the new cars were EVs, and each had a 50 kWh battery, we'd have to somehow produce 1.35 billion kWh of batteries. The already existing EVs would consume batteries at a rate approximately 1/10th their capacity a year, so 350 million EVs would require an additional 1.75 billion kWh a year.

This sort of demand would exceed the current world production of lithium 12 times.

Now you might point out that lithium batteries can be recycled, but there is one huge issue: lithium batteries are recycled, but there is practically no recycling going on because the virgin material is cheaper, and it has to be.

To meet the predictions of demand for EVs in the near future, battery prices must come DOWN dramatically, but to meet the demand for production the battery prices must go UP dramatically to scale up the industry. An impossible case

Jun 25, 2017
Eikka:
The whole point of the article


The whole point of this article is whether oxymethylene ether is a practical replacement at all for diesel, to reduce NOx, soot and get "sustainable CO2". The article doesn't say how the OME is produced, though it says the lead researcher is "excited about the technical process chain involved in the production of" it.

"Synthetic fuels" are not necessarily carbon-neutral:
"from syngas, [...] derived from [...] coal or biomass or by reforming of natural gas."
https://en.wikipe...tic_fuel

This article doesn't link to any underlying publication. Googling the TUD and Beidl turned up his recent paper "Oxymethylene Ether (OME1) as Synthetic Low Emission Fuel for DI Diesel Engines", which does focus on its carbon-neutral production:
https://link.spri...918-7_41

The facts make me enthusiastic about OME1. I want to know its production process, and I'm optimistic it's a sustainable one.

Jun 25, 2017
CO2 is not the only thing that's bad about burning fuels.

Let's not forget that buring fuel (be it fossil or synthetic) also creates soot and NOx. Always. The above article also addresses reducing these emissions (but you can't really eliminate them, because chemistry doesn't work that way. At it's heart it's probabilistic so you can only ever shift the balance but not eliminate these side products altogether).

It's a step in the right direction for sectors where the changeover to batteries or hydrogen will take a bit longer (trucking, and possibly shipping). But at the end of the day this is a stopgap measure at best.

Jun 25, 2017
Eikka:
we'd have to somehow produce 1.35 billion kWh of batteries.


You've possibly seen my posts in other article discussions wanting to see for example offshore solar cracking atmospheric CO2 into liquid fuels, distributed by existing maritime tankers, ports and the rest of the existing petrofuel infrastructure. Continuing to use that infrastructure, not replacing it, also saves a lot of pollution. I'm only against the worsening Greenhouse.

And secondarily against the geopolitics of petrofuel production. I'm not nearly as unhappy about the other health problems like particulates, but they're important in proportion. But quickly reversing the Greenhouse growth is essential, and carbon-neutral fuels are the rapidest replacement with the smallest costs. And indeed the capacity of the global petrofuel storage/distribution system is a good managed sink for carbon.

Jun 25, 2017
Eikka:
To meet the predictions of demand for EVs in the near future, battery prices must come DOWN dramatically, but to meet the demand for production the battery prices must go UP dramatically to scale up the industry.


Battery prices need not go up to dramatically scale up the industry. Price elasticity: for P% of price decrease unit sales typically increase by 1/P% (ie. P*). Indeed as battery prices have decreased rapidly (smaller unit profit margin) with increasing manufacturing scales, many more units have been sold at greater gross profit.

Plus other scale economies, including reinvested revenue into more efficient production. Meanwhile Chinese and other hazardous lithium production is increasingly unsupportable for health and other reasons, pressuring recycling, even as that becomes cheaper through defragmenting the source chemistries/assemblies and innovations.

More efficient electrodes, storage chemistries, etc. <$120:KWh already, headed below $100 by 2020.

Jun 25, 2017
antialias_physorg:
It's a step in the right direction for sectors where the changeover to batteries or hydrogen will take a bit longer (trucking, and possibly shipping). But at the end of the day this is a stopgap measure at best.


Everything is always transitional. If we survive and learn, and remain homo sapiens, 2100 could see photonic vehicles or some other energy system not yet realized.

If carbon-neutral fuels can be made using anything close to current refineries, and use anything close to current petrofuel distribution, even if ICEs are reengineered for them (not necessary with OME1) they'll dominate the replacement of petrofuels for decades, even as EV grows at current projections.

Which is OK: we don't have to actually eliminate all human CO2e pollution to survive. Humans overload the planet with 11.7Gt annual excess, about 60% of our artificial emissions. Cutting >60% could be necessary to reverse the Greenhouse, but not 100%.

Jun 25, 2017
Eikka
Now you might point out that lithium batteries can be recycled, but there is one huge issue: lithium batteries are recycled, but there is practically no recycling going on because the virgin material is cheaper, and it has to be.


Making new lithium batteries doesn't have to be cheaper than recycling new ones. A Swedish research group is already getting past some of the bottlenecks in making recycling cheaper than new material:
https://www.tu.no...m/376939

A remaining bottleneck is too few batteries to work with, but of course that is changing rapidly. Especially MTBF of batteries is years, but the pipeline has been loaded with lots of new EVs for several years. This will compound especially as tech innovation reclaims larger categories of batteries.

Jun 26, 2017
Everything is always transitional.

What I emant was that this isn't a solution where we go "let's not worry about the issue any further". Inner city soot/NOx levels are a problem. Soot from shipping is a problem. While fully electric or hydrogen shipping/trucking isn't something we can do next year it is still something that needs to be researched and implemented at all possible speed.

we don't have to actually eliminate all human CO2 pollution to survive

Sure, but the more we can eliminate the better - and if we can do it with even less ancillary pollution than using synthetic fuels: even better. The faster and the more we cuut the shorter we'll have to pay to mitigate damages. It just makes a fiscal sense (long term).
(I fully realize that politics isn't interested in 'long term'. But some people are. The idea is to have a better place to live in - not just one without a greenhouse effect)

Jun 26, 2017
antialias_physorg:
Sure, but the more we can eliminate the better


I agree with you here too. Carbon neutral just maintains the atmospheric/oceanic CO2e levels from that point, and we must remediate something like 25% of the atmospheric (and a smaller fraction of the larger total oceanic) to sustain a civilization and perhaps our species itself.

The scale and complexity of the pollution problem (Greenhouse and health), and hence its "solution", are so large and intertwined with our civilization and culture that we have to do everything we can that doesn't create worse existential problems. Everything is going to be transitional, we're going to be coping (sometimes by writing off and mourning) with damage even when we also fully maintain other flows.

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