Our new President will not let that happen.
Four Cities to ban diesel vehicles by 2025
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Originally Posted By: JHZR2
This picture says it all.
Diesel has better thermal efficiency and better longevity than gas engines do. That makes a big difference in heavy duty work, and even for many who want the most economical way to transport themselves around. I can't see how anything but perhaps a diesel electric (similar to a train) would work for heavy duty hauling vehicles
I post that same picture all the time. Few people take the time to understand it.
1) Gasoline and Diesel fuel have very much the same energy PER POUND (per unit weight, G, KG, Ounce)
2) Thermal efficiency of common, modern, internal combustion gasoline engines is in the 20% to mid 30% range. (cars trucks generators) Remember, thermal efficiency at idle is exactly zero! The modern Prius touches on 40% in some operational zones! Modern larger diesels can approach 40%.
3) While ethanol does not contain as much energy, either by mass, or by volume, Ethanol fueled engines CAN MATCH modern diesel engines in thermal efficiency!
4) A high compression ratio, and the resulting better expansion ratio is a major factor in thermal efficiency.
5) The surface area to volume ratio of a cylinder strongly favors larger cylinders! As more surface area per displacement will transfer heat out of the combustion chamber more effectively, thereby lowering thermal efficiency.
Hard working engines could be ethanol, propane or LNG fueled without any real change in performance or thermal efficiency. They simply would have to carry more fuel volume for a particular job.
Ricardo (as have many others) has developed an ethanol fueled engine with excellent thermal efficiency and overall excellent MPG. It's designed as you would expect. Very high compression ratio, direct injection, turbocharged and very, very tough.
This is one possible answer to the diesel emissions situation. There are large trucks successfully powered by ethanol. The HP produced by well designed ethanol engines far exceeds diesel engines. Allowing for a smaller engine. For a wild by absurd example, the Honda S2000 guys running on E-85 fuel regularly make 750HP from 2.2L displacement, reliably. As there is near zero risk of damaging detonation.
Here is Scania's 3rd generation heavy duty Ethanol truck engine:
This picture says it all.
Diesel has better thermal efficiency and better longevity than gas engines do. That makes a big difference in heavy duty work, and even for many who want the most economical way to transport themselves around. I can't see how anything but perhaps a diesel electric (similar to a train) would work for heavy duty hauling vehicles
I post that same picture all the time. Few people take the time to understand it.
1) Gasoline and Diesel fuel have very much the same energy PER POUND (per unit weight, G, KG, Ounce)
2) Thermal efficiency of common, modern, internal combustion gasoline engines is in the 20% to mid 30% range. (cars trucks generators) Remember, thermal efficiency at idle is exactly zero! The modern Prius touches on 40% in some operational zones! Modern larger diesels can approach 40%.
3) While ethanol does not contain as much energy, either by mass, or by volume, Ethanol fueled engines CAN MATCH modern diesel engines in thermal efficiency!
4) A high compression ratio, and the resulting better expansion ratio is a major factor in thermal efficiency.
5) The surface area to volume ratio of a cylinder strongly favors larger cylinders! As more surface area per displacement will transfer heat out of the combustion chamber more effectively, thereby lowering thermal efficiency.
Hard working engines could be ethanol, propane or LNG fueled without any real change in performance or thermal efficiency. They simply would have to carry more fuel volume for a particular job.
Ricardo (as have many others) has developed an ethanol fueled engine with excellent thermal efficiency and overall excellent MPG. It's designed as you would expect. Very high compression ratio, direct injection, turbocharged and very, very tough.
This is one possible answer to the diesel emissions situation. There are large trucks successfully powered by ethanol. The HP produced by well designed ethanol engines far exceeds diesel engines. Allowing for a smaller engine. For a wild by absurd example, the Honda S2000 guys running on E-85 fuel regularly make 750HP from 2.2L displacement, reliably. As there is near zero risk of damaging detonation.
Here is Scania's 3rd generation heavy duty Ethanol truck engine:
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Originally Posted By: wemay
Diesel elimination was being discussed on a BBC radio show this morning. Government officials, Scania and Mercedes representatives participated. The consensus being this is now reality and will spread to other locations without fail. The fact that many bitogers fail to see the logic not withstanding. This move will be exorbitantly expensive.
In most European cities, diesel exhaust is a real problem, but most European cars are diesels these days.
In contrast, our sprawling metro areas are far less densely populated and diesel passenger cars are a rarity, with VW having helped to keep it that way.
While getting rid of or greatly reducing the number of diesel powered vehicles in European cities might make great sense, it would probably make little difference in this country.
It's all about the number of diesels in use as well as the population densities involved.
IOW, what might or might not be coming in the EU has no bearing on this country since we don't have the same problem to solve.
Diesel elimination was being discussed on a BBC radio show this morning. Government officials, Scania and Mercedes representatives participated. The consensus being this is now reality and will spread to other locations without fail. The fact that many bitogers fail to see the logic not withstanding. This move will be exorbitantly expensive.
In most European cities, diesel exhaust is a real problem, but most European cars are diesels these days.
In contrast, our sprawling metro areas are far less densely populated and diesel passenger cars are a rarity, with VW having helped to keep it that way.
While getting rid of or greatly reducing the number of diesel powered vehicles in European cities might make great sense, it would probably make little difference in this country.
It's all about the number of diesels in use as well as the population densities involved.
IOW, what might or might not be coming in the EU has no bearing on this country since we don't have the same problem to solve.
wemay
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Agreed. This country was never big on diesel passenger vehicles and all our city buses seem to be moving towards electric. For the average citizen, out of sight, out of mind. Transportation of goods falls into this frame of mind.
JHZR2
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Originally Posted By: wemay
Agreed. This country was never big on diesel passenger vehicles and all our city buses seem to be moving towards electric. For the average citizen, out of sight, out of mind. Transportation of goods falls into this frame of mind.
Which is ridiculous. For a vehicle that does a lot of load or a lot of distance driving, like is the norm in the USA a good diesel is really the best option.
The rest of the world recognizes it. Were constrained by a little strip of land west of the Sierras, that has terible air quality, and affects the decisions of the rest of the USA.
Somehow an 8 MPG gas engine can be partial zero emissions, while a 50 MPG diesel can be a gross polluter. I get it that there is some NOx and some PM, but its still insanity.
Agreed. This country was never big on diesel passenger vehicles and all our city buses seem to be moving towards electric. For the average citizen, out of sight, out of mind. Transportation of goods falls into this frame of mind.
Which is ridiculous. For a vehicle that does a lot of load or a lot of distance driving, like is the norm in the USA a good diesel is really the best option.
The rest of the world recognizes it. Were constrained by a little strip of land west of the Sierras, that has terible air quality, and affects the decisions of the rest of the USA.
Somehow an 8 MPG gas engine can be partial zero emissions, while a 50 MPG diesel can be a gross polluter. I get it that there is some NOx and some PM, but its still insanity.
It's all a matter of compliance with emissions standards as measured in grams per mile.
That 8 mpg truck can comply while cheap diesels can't.
This is the problem VW finds itself with now.
The rest of the world is also apparently coming to realize that diesel emissions have a horrible impact on urban air quality.
Visit a European city and see for yourself. LA in the sixties would have been better.
That 8 mpg truck can comply while cheap diesels can't.
This is the problem VW finds itself with now.
The rest of the world is also apparently coming to realize that diesel emissions have a horrible impact on urban air quality.
Visit a European city and see for yourself. LA in the sixties would have been better.
Originally Posted By: JHZR2
Somehow an 8 MPG gas engine can be partial zero emissions, while a 50 MPG diesel can be a gross polluter. I get it that there is some NOx and some PM, but its still insanity.
As crazy as it sounds, the folks who "make up the rules" (here in the USA, it's the EPA) clearly understand this too. Yet they will willingly sacrifice considerable thermal efficiency to meet a "numerical" goal, while knowingly increasing CO2 output.
At the moment, the best answer to overall tailpipe emissions seems to be the hybrid-electric car and truck. With very modest battery capacity. The Prius, Accord, Camry and a few other hybrids seem to be best able to reduce all numbers.
Somehow an 8 MPG gas engine can be partial zero emissions, while a 50 MPG diesel can be a gross polluter. I get it that there is some NOx and some PM, but its still insanity.
As crazy as it sounds, the folks who "make up the rules" (here in the USA, it's the EPA) clearly understand this too. Yet they will willingly sacrifice considerable thermal efficiency to meet a "numerical" goal, while knowingly increasing CO2 output.
At the moment, the best answer to overall tailpipe emissions seems to be the hybrid-electric car and truck. With very modest battery capacity. The Prius, Accord, Camry and a few other hybrids seem to be best able to reduce all numbers.
Short hauls in Europe are one thing. Long hauls in the US is quite another. The difference in running cost between diesels and alternatives is huge over long distances. Probably would double the price of fresh produce and meats in some US markets.
Originally Posted By: SeaJay
Short hauls in Europe are one thing. Long hauls in the US is quite another. The difference in running cost between diesels and alternatives is huge over long distances. Probably would double the price of fresh produce and meats in some US markets.
I don't agree. The Scania ethanol fueled engine above is 44% thermally efficient. With ethanol's lower fuel cost, the overall operational cost is likely to be quite similar. Around here, ethanol is so much cheaper, there would be no net change in fuel costs.
Short hauls in Europe are one thing. Long hauls in the US is quite another. The difference in running cost between diesels and alternatives is huge over long distances. Probably would double the price of fresh produce and meats in some US markets.
I don't agree. The Scania ethanol fueled engine above is 44% thermally efficient. With ethanol's lower fuel cost, the overall operational cost is likely to be quite similar. Around here, ethanol is so much cheaper, there would be no net change in fuel costs.
Originally Posted By: Jarlaxle
Do you or do you not understand the YAWNING CHASM (BTU/gallon) between the energy density of ethanol and tbat of diesel fuel?
If that is directed at me, don't be that guy. I clearly acknowledged the lower energy content of ethanol, and noted it's locally significantly lower cost.
I am not an ethanol fanboi, far from it. I simply noted that "IF" it's used in trucks with 44% TE engines, (similar to the ultra high compression, direct injection, turbocharged Scania engine) operational costs will remain status quo.
Will the EPA allow such engines? I don't know. It seems questionable at best.
Is the lifecycle of emissions for ethanol better? Nope. Nor is the tailpipe CO2 output. Not surprisingly, gasoline and E-85 produce nearly the same CO2 per gal consumed.
Here is an interesting study, make of it what you'd like: http://www.afdc.energy.gov/pdfs/casestudy_adm.pdf
Do you or do you not understand the YAWNING CHASM (BTU/gallon) between the energy density of ethanol and tbat of diesel fuel?
If that is directed at me, don't be that guy. I clearly acknowledged the lower energy content of ethanol, and noted it's locally significantly lower cost.
I am not an ethanol fanboi, far from it. I simply noted that "IF" it's used in trucks with 44% TE engines, (similar to the ultra high compression, direct injection, turbocharged Scania engine) operational costs will remain status quo.
Will the EPA allow such engines? I don't know. It seems questionable at best.
Is the lifecycle of emissions for ethanol better? Nope. Nor is the tailpipe CO2 output. Not surprisingly, gasoline and E-85 produce nearly the same CO2 per gal consumed.
Here is an interesting study, make of it what you'd like: http://www.afdc.energy.gov/pdfs/casestudy_adm.pdf
Originally Posted By: Cujet
Originally Posted By: Jarlaxle
Do you or do you not understand the YAWNING CHASM (BTU/gallon) between the energy density of ethanol and tbat of diesel fuel?
If that is directed at me, don't be that guy. I clearly acknowledged the lower energy content of ethanol, and noted it's locally significantly lower cost.
I am not an ethanol fanboi, far from it. I simply noted that "IF" it's used in trucks with 44% TE engines, (similar to the ultra high compression, direct injection, turbocharged Scania engine) operational costs will remain status quo.
Will the EPA allow such engines? I don't know. It seems questionable at best.
Is the lifecycle of emissions for ethanol better? Nope. Nor is the tailpipe CO2 output. Not surprisingly, gasoline and E-85 produce nearly the same CO2 per gal consumed.
Here is an interesting study, make of it what you'd like: http://www.afdc.energy.gov/pdfs/casestudy_adm.pdf
Never mind the fact that a 44% efficient engine can be built specifically to operate on ethanol. That doesn't mean that operating cost will be the same as with petroleum fuels. Thermal efficiency is ratio of mechanical power out / chemical power in. Chemical power in = gal/hr fuel flow x BTU/gal of fuel. Because the energy content of ethanol is about 42% less than diesel per gallon, that means that 42% more fuel must be bought by the operator to do the same amount of work. It would be economically equivalent only if E100 was 42% cheaper by the gallon than diesel, and I really doubt that would be the case. It's also a stretch to assume that the ethanol optimized engine would have as large a fuel economy sweet spot as a diesel of comparable power rating if the ethanol engine is operating under throttled conditions at part load.
Originally Posted By: Jarlaxle
Do you or do you not understand the YAWNING CHASM (BTU/gallon) between the energy density of ethanol and tbat of diesel fuel?
If that is directed at me, don't be that guy. I clearly acknowledged the lower energy content of ethanol, and noted it's locally significantly lower cost.
I am not an ethanol fanboi, far from it. I simply noted that "IF" it's used in trucks with 44% TE engines, (similar to the ultra high compression, direct injection, turbocharged Scania engine) operational costs will remain status quo.
Will the EPA allow such engines? I don't know. It seems questionable at best.
Is the lifecycle of emissions for ethanol better? Nope. Nor is the tailpipe CO2 output. Not surprisingly, gasoline and E-85 produce nearly the same CO2 per gal consumed.
Here is an interesting study, make of it what you'd like: http://www.afdc.energy.gov/pdfs/casestudy_adm.pdf
Never mind the fact that a 44% efficient engine can be built specifically to operate on ethanol. That doesn't mean that operating cost will be the same as with petroleum fuels. Thermal efficiency is ratio of mechanical power out / chemical power in. Chemical power in = gal/hr fuel flow x BTU/gal of fuel. Because the energy content of ethanol is about 42% less than diesel per gallon, that means that 42% more fuel must be bought by the operator to do the same amount of work. It would be economically equivalent only if E100 was 42% cheaper by the gallon than diesel, and I really doubt that would be the case. It's also a stretch to assume that the ethanol optimized engine would have as large a fuel economy sweet spot as a diesel of comparable power rating if the ethanol engine is operating under throttled conditions at part load.
Originally Posted By: A_Harman
It would be economically equivalent only if E100 was 42% cheaper by the gallon than diesel, and I really doubt that would be the case.
Yes, locally, today, it's roughly 25% less expensive. Back at the end of November, E100 was $1.41/gal. I can't predict the future, and how much more E100 would be if required for certain trucks nationwide. I suspect it would be impossible to produce that much ethanol.
But I don't see Ethanol powered trucks doubling the cost of goods, as claimed above. Petro fuels vary in price far more than any "ethanol differential" operational costs.
Yikes, I'd better stop. My motto is: "if it doesn't burn fossil fuel, I don't like it"
I do love all things mechanical, especially motorsports.
It would be economically equivalent only if E100 was 42% cheaper by the gallon than diesel, and I really doubt that would be the case.
Yes, locally, today, it's roughly 25% less expensive. Back at the end of November, E100 was $1.41/gal. I can't predict the future, and how much more E100 would be if required for certain trucks nationwide. I suspect it would be impossible to produce that much ethanol.
But I don't see Ethanol powered trucks doubling the cost of goods, as claimed above. Petro fuels vary in price far more than any "ethanol differential" operational costs.
Yikes, I'd better stop. My motto is: "if it doesn't burn fossil fuel, I don't like it"
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[/quote]
Yes, locally, today, it's roughly 25% less expensive. Back at the end of November, E100 was $1.41/gal. I can't predict the future, and how much more E100 would be if required for certain trucks nationwide. I suspect it would be impossible to produce that much ethanol. [/quote]
Ethanol closed yesterday at 1.66 a gallon. companies would be foolish to plan their models after government mandates that can be changed from one administration to another.
But think about where were we 40 years ago. Up until the mid seventies we were still running points and they had just started catalytic converters. Forty years from now you won't even be able to purchase a diesel for personal use. maybe not even your own car. look at how everything is going. self-driving cars. uber, lyft. the whole electric thing.
It makes me depressed
Yes, locally, today, it's roughly 25% less expensive. Back at the end of November, E100 was $1.41/gal. I can't predict the future, and how much more E100 would be if required for certain trucks nationwide. I suspect it would be impossible to produce that much ethanol. [/quote]
Ethanol closed yesterday at 1.66 a gallon. companies would be foolish to plan their models after government mandates that can be changed from one administration to another.
But think about where were we 40 years ago. Up until the mid seventies we were still running points and they had just started catalytic converters. Forty years from now you won't even be able to purchase a diesel for personal use. maybe not even your own car. look at how everything is going. self-driving cars. uber, lyft. the whole electric thing.
It makes me depressed
If Musk has his way, driving a vehicle will be something you obtain his permission to do, if you're a good boy and keep quiet.
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