Emissions old cars v gas guzzlers
Discussion
I have been trying to get my head around this for ages, brought it up in various discussions on PH, spent hours on google and you tube looking for an answer, how is a New Bentley for example that does 9mpg in traffic less poll then an older say 20 year old fiesta that does 30mpg in traffic. As far as I can tell the engines work kind if the same way, I guess the emissions from the Bentley get caught some how, but what happens to them,
As you can tell i need a for dummies answer.
As you can tell i need a for dummies answer.
NOx is the answer you're looking for. It's nothing to do with consumption; it's to do with emissions.
NOx gases are usually produced from the reaction between nitrogen and oxygen during combustion of fuels, such as hydrocarbons, in air; especially at high temperatures, such as in car engines. In areas of high motor vehicle traffic, such as in large cities, the nitrogen oxides emitted can be a significant source of air pollution.
When NOx and volatile organic compounds react in the presence of sunlight, they form photochemical smog, a significant form of air pollution. The presence of photochemical smog increases during the summer when the incident solar radiation is higher. The emitted hydrocarbons from industrial activities and transportation react with NOx quickly and increase the concentration of ozone and peroxide compounds, especially peroxyacetyl nitrate.
Children, people with lung diseases such as asthma, and people who work or exercise outside are particularly susceptible to adverse effects of smog such as damage to lung tissue and reduction in lung function.
It is estimated that transportation fuels cause 54% of human-caused NOx.
Catalytic converters reduce post combustion NOx by reacting the exhaust with urea or ammonia to produce nitrogen and water. SCR is now being used in ships, diesel trucks and in some diesel cars. The use of exhaust gas recirculation and catalytic converters in motor vehicle engines have significantly reduced vehicular emissions.
NOx gases are usually produced from the reaction between nitrogen and oxygen during combustion of fuels, such as hydrocarbons, in air; especially at high temperatures, such as in car engines. In areas of high motor vehicle traffic, such as in large cities, the nitrogen oxides emitted can be a significant source of air pollution.
When NOx and volatile organic compounds react in the presence of sunlight, they form photochemical smog, a significant form of air pollution. The presence of photochemical smog increases during the summer when the incident solar radiation is higher. The emitted hydrocarbons from industrial activities and transportation react with NOx quickly and increase the concentration of ozone and peroxide compounds, especially peroxyacetyl nitrate.
Children, people with lung diseases such as asthma, and people who work or exercise outside are particularly susceptible to adverse effects of smog such as damage to lung tissue and reduction in lung function.
It is estimated that transportation fuels cause 54% of human-caused NOx.
Catalytic converters reduce post combustion NOx by reacting the exhaust with urea or ammonia to produce nitrogen and water. SCR is now being used in ships, diesel trucks and in some diesel cars. The use of exhaust gas recirculation and catalytic converters in motor vehicle engines have significantly reduced vehicular emissions.
Panamax said:
NOx is the answer you're looking for. It's nothing to do with consumption; it's to do with emissions.
NOx gases are usually produced from the reaction between nitrogen and oxygen during combustion of fuels, such as hydrocarbons, in air; especially at high temperatures, such as in car engines. In areas of high motor vehicle traffic, such as in large cities, the nitrogen oxides emitted can be a significant source of air pollution.
When NOx and volatile organic compounds react in the presence of sunlight, they form photochemical smog, a significant form of air pollution. The presence of photochemical smog increases during the summer when the incident solar radiation is higher. The emitted hydrocarbons from industrial activities and transportation react with NOx quickly and increase the concentration of ozone and peroxide compounds, especially peroxyacetyl nitrate.
Children, people with lung diseases such as asthma, and people who work or exercise outside are particularly susceptible to adverse effects of smog such as damage to lung tissue and reduction in lung function.
It is estimated that transportation fuels cause 54% of human-caused NOx.
Catalytic converters reduce post combustion NOx by reacting the exhaust with urea or ammonia to produce nitrogen and water. SCR is now being used in ships, diesel trucks and in some diesel cars. The use of exhaust gas recirculation and catalytic converters in motor vehicle engines have significantly reduced vehicular emissions.
Thanks for your reply, but my 1999 car has a cat, so has my 2014 diesel, so why is it not compliant with ULEZ???NOx gases are usually produced from the reaction between nitrogen and oxygen during combustion of fuels, such as hydrocarbons, in air; especially at high temperatures, such as in car engines. In areas of high motor vehicle traffic, such as in large cities, the nitrogen oxides emitted can be a significant source of air pollution.
When NOx and volatile organic compounds react in the presence of sunlight, they form photochemical smog, a significant form of air pollution. The presence of photochemical smog increases during the summer when the incident solar radiation is higher. The emitted hydrocarbons from industrial activities and transportation react with NOx quickly and increase the concentration of ozone and peroxide compounds, especially peroxyacetyl nitrate.
Children, people with lung diseases such as asthma, and people who work or exercise outside are particularly susceptible to adverse effects of smog such as damage to lung tissue and reduction in lung function.
It is estimated that transportation fuels cause 54% of human-caused NOx.
Catalytic converters reduce post combustion NOx by reacting the exhaust with urea or ammonia to produce nitrogen and water. SCR is now being used in ships, diesel trucks and in some diesel cars. The use of exhaust gas recirculation and catalytic converters in motor vehicle engines have significantly reduced vehicular emissions.
Oliver Hardy said:
Panamax said:
NOx is the answer you're looking for. It's nothing to do with consumption; it's to do with emissions.
NOx gases are usually produced from the reaction between nitrogen and oxygen during combustion of fuels, such as hydrocarbons, in air; especially at high temperatures, such as in car engines. In areas of high motor vehicle traffic, such as in large cities, the nitrogen oxides emitted can be a significant source of air pollution.
When NOx and volatile organic compounds react in the presence of sunlight, they form photochemical smog, a significant form of air pollution. The presence of photochemical smog increases during the summer when the incident solar radiation is higher. The emitted hydrocarbons from industrial activities and transportation react with NOx quickly and increase the concentration of ozone and peroxide compounds, especially peroxyacetyl nitrate.
Children, people with lung diseases such as asthma, and people who work or exercise outside are particularly susceptible to adverse effects of smog such as damage to lung tissue and reduction in lung function.
It is estimated that transportation fuels cause 54% of human-caused NOx.
Catalytic converters reduce post combustion NOx by reacting the exhaust with urea or ammonia to produce nitrogen and water. SCR is now being used in ships, diesel trucks and in some diesel cars. The use of exhaust gas recirculation and catalytic converters in motor vehicle engines have significantly reduced vehicular emissions.
Thanks for your reply, but my 1999 car has a cat, so has my 2014 diesel, so why is it not compliant with ULEZ???NOx gases are usually produced from the reaction between nitrogen and oxygen during combustion of fuels, such as hydrocarbons, in air; especially at high temperatures, such as in car engines. In areas of high motor vehicle traffic, such as in large cities, the nitrogen oxides emitted can be a significant source of air pollution.
When NOx and volatile organic compounds react in the presence of sunlight, they form photochemical smog, a significant form of air pollution. The presence of photochemical smog increases during the summer when the incident solar radiation is higher. The emitted hydrocarbons from industrial activities and transportation react with NOx quickly and increase the concentration of ozone and peroxide compounds, especially peroxyacetyl nitrate.
Children, people with lung diseases such as asthma, and people who work or exercise outside are particularly susceptible to adverse effects of smog such as damage to lung tissue and reduction in lung function.
It is estimated that transportation fuels cause 54% of human-caused NOx.
Catalytic converters reduce post combustion NOx by reacting the exhaust with urea or ammonia to produce nitrogen and water. SCR is now being used in ships, diesel trucks and in some diesel cars. The use of exhaust gas recirculation and catalytic converters in motor vehicle engines have significantly reduced vehicular emissions.
Oliver Hardy said:
Thanks for your reply, but my 1999 car has a cat, so has my 2014 diesel, so why is it not compliant with ULEZ???
Because your car has 1 Cat. More modern vehicles will have up to 4 cats, 4+ Exhaust gas sensors, a Petrol Particular Filter and a much more modern ECU to control all of the above. Similar story to pre-2014 Diesels having less sophisticated emissions controlthat more modern diesels have (Adblue)
A perfectly clean engine would inhale air (nitrogen, oxygen, bits and pieces of other stuff), add fuel (carbon and hydrogen) and emit carbon dioxide and water vapour in proportion to the amount of fuel you put in, and the air it inhaled unchanged minus the oxygen it used to burn the fuel.
This is still a problem, because we have a carbon dioxide climate thing going on, but it's not going to do you any immediate physical harm at reasonable concentrations.
Engines aren't in practice perfectly clean. They fail to burn all of the fuel, leaving variously particles of carbon, fragments of fuel molecules, and carbon monoxide in the exhaust. They also sometimes burn the nitrogen in the air, releasing oxides of nitrogen in the exhaust. These are all things you do not want to be breathing in. The oxides of nitrogen are acidic, and irritate the lungs. The unburnt fuel fragments are carcinogenic. The particles of carbon damage the cardiovascular system, and are often coated in those carcinogenic substances. The carbon monoxide binds with the haemoglobin in blood and stops it being able to carry oxygen round your body. And once these things are in the local air, they react with each other, especially when exposed to sunlight, and generate other unpleasant substances like ozone.
We design engines to reduce these emissions and have done so massively over the years. We run the exhaust through catalytic converters, which complete the burning process of the fuel, nicking back the oxygen from the oxides of nitrogen in the process, effectively "unburning" it. We filter out the particles of carbon. We tightly manage the combustion process to reduce the production of all this crap in the first place. New cars have got incrementally cleaner over the years and old cars drop out of the picture by natural wastage.
This is still a problem, because we have a carbon dioxide climate thing going on, but it's not going to do you any immediate physical harm at reasonable concentrations.
Engines aren't in practice perfectly clean. They fail to burn all of the fuel, leaving variously particles of carbon, fragments of fuel molecules, and carbon monoxide in the exhaust. They also sometimes burn the nitrogen in the air, releasing oxides of nitrogen in the exhaust. These are all things you do not want to be breathing in. The oxides of nitrogen are acidic, and irritate the lungs. The unburnt fuel fragments are carcinogenic. The particles of carbon damage the cardiovascular system, and are often coated in those carcinogenic substances. The carbon monoxide binds with the haemoglobin in blood and stops it being able to carry oxygen round your body. And once these things are in the local air, they react with each other, especially when exposed to sunlight, and generate other unpleasant substances like ozone.
We design engines to reduce these emissions and have done so massively over the years. We run the exhaust through catalytic converters, which complete the burning process of the fuel, nicking back the oxygen from the oxides of nitrogen in the process, effectively "unburning" it. We filter out the particles of carbon. We tightly manage the combustion process to reduce the production of all this crap in the first place. New cars have got incrementally cleaner over the years and old cars drop out of the picture by natural wastage.
otolith said:
A perfectly clean engine would inhale air (nitrogen, oxygen, bits and pieces of other stuff), add fuel (carbon and hydrogen) and emit carbon dioxide and water vapour in proportion to the amount of fuel you put in, and the air it inhaled unchanged minus the oxygen it used to burn the fuel.
This is still a problem, because we have a carbon dioxide climate thing going on, but it's not going to do you any immediate physical harm at reasonable concentrations.
Engines aren't in practice perfectly clean. They fail to burn all of the fuel, leaving variously particles of carbon, fragments of fuel molecules, and carbon monoxide in the exhaust. They also sometimes burn the nitrogen in the air, releasing oxides of nitrogen in the exhaust. These are all things you do not want to be breathing in. The oxides of nitrogen are acidic, and irritate the lungs. The unburnt fuel fragments are carcinogenic. The particles of carbon damage the cardiovascular system, and are often coated in those carcinogenic substances. The carbon monoxide binds with the haemoglobin in blood and stops it being able to carry oxygen round your body. And once these things are in the local air, they react with each other, especially when exposed to sunlight, and generate other unpleasant substances like ozone.
We design engines to reduce these emissions and have done so massively over the years. We run the exhaust through catalytic converters, which complete the burning process of the fuel, nicking back the oxygen from the oxides of nitrogen in the process, effectively "unburning" it. We filter out the particles of carbon. We tightly manage the combustion process to reduce the production of all this crap in the first place. New cars have got incrementally cleaner over the years and old cars drop out of the picture by natural wastage.
This is still a problem, because we have a carbon dioxide climate thing going on, but it's not going to do you any immediate physical harm at reasonable concentrations.
Engines aren't in practice perfectly clean. They fail to burn all of the fuel, leaving variously particles of carbon, fragments of fuel molecules, and carbon monoxide in the exhaust. They also sometimes burn the nitrogen in the air, releasing oxides of nitrogen in the exhaust. These are all things you do not want to be breathing in. The oxides of nitrogen are acidic, and irritate the lungs. The unburnt fuel fragments are carcinogenic. The particles of carbon damage the cardiovascular system, and are often coated in those carcinogenic substances. The carbon monoxide binds with the haemoglobin in blood and stops it being able to carry oxygen round your body. And once these things are in the local air, they react with each other, especially when exposed to sunlight, and generate other unpleasant substances like ozone.
We design engines to reduce these emissions and have done so massively over the years. We run the exhaust through catalytic converters, which complete the burning process of the fuel, nicking back the oxygen from the oxides of nitrogen in the process, effectively "unburning" it. We filter out the particles of carbon. We tightly manage the combustion process to reduce the production of all this crap in the first place. New cars have got incrementally cleaner over the years and old cars drop out of the picture by natural wastage.
Well put and explained.
I have just received my Crit'Air sticker here in France for my 2017 S550 Mustang GT and was very surprised to find its classed as 1 just below the full electric and hybrid vehicles (class 0). System goes from 0 down to 5 and needed to go into some of the large cities in France these days.
Having great fun seeing the bemused looks of peoples faces, when they see the sticker in the windshield.
I have just received my Crit'Air sticker here in France for my 2017 S550 Mustang GT and was very surprised to find its classed as 1 just below the full electric and hybrid vehicles (class 0). System goes from 0 down to 5 and needed to go into some of the large cities in France these days.
Having great fun seeing the bemused looks of peoples faces, when they see the sticker in the windshield.
rolster said:
Well put and explained.
I have just received my Crit'Air sticker here in France for my 2017 S550 Mustang GT and was very surprised to find its classed as 1 just below the full electric and hybrid vehicles (class 0). System goes from 0 down to 5 and needed to go into some of the large cities in France these days.
Having great fun seeing the bemused looks of peoples faces, when they see the sticker in the windshield.
More likely they are just gawping at the unfamiliar sight of a Mustang; whilst they are ten-a-penny here, I've only seen a few in France. Performance cars just don't seem to be popular in France; I have just received my Crit'Air sticker here in France for my 2017 S550 Mustang GT and was very surprised to find its classed as 1 just below the full electric and hybrid vehicles (class 0). System goes from 0 down to 5 and needed to go into some of the large cities in France these days.
Having great fun seeing the bemused looks of peoples faces, when they see the sticker in the windshield.
Since crit'air began I've rumbled through various crit'air zones with a variety of loud V8s and no-one donnered a merde let alone pointed at my sticker in shock and disbelief.
Edited by donkmeister on Thursday 7th September 01:15
donkmeister said:
rolster said:
Well put and explained.
I have just received my Crit'Air sticker here in France for my 2017 S550 Mustang GT and was very surprised to find its classed as 1 just below the full electric and hybrid vehicles (class 0). System goes from 0 down to 5 and needed to go into some of the large cities in France these days.
Having great fun seeing the bemused looks of peoples faces, when they see the sticker in the windshield.
More likely they are just gawping at the unfamiliar sight of a Mustang; whilst they are ten-a-penny here, I've only seen a few in France. Performance cars just don't seem to be popular in France; I have just received my Crit'Air sticker here in France for my 2017 S550 Mustang GT and was very surprised to find its classed as 1 just below the full electric and hybrid vehicles (class 0). System goes from 0 down to 5 and needed to go into some of the large cities in France these days.
Having great fun seeing the bemused looks of peoples faces, when they see the sticker in the windshield.
Since crit'air began I've rumbled through various crit'air zones with a variety of loud V8s and no-one donnered a merde let alone pointed at my sticker in shock and disbelief.
Edited by donkmeister on Thursday 7th September 01:15
For purchasing performance cars in France there is a heavy eco tax applied on top of the purchase price, i paid nearly a twenty percent premium for the eco tax when purchasing the Mustang which will be why allot of people don't by performance cars.
The mustang in France is quite a peculiar car as the French generally seem to be very friendly towards it. I have had Ferrari and Porsche's before and would not be given the time of day, but am often chatted to with the Mustang. I am not sure the reason why.
Interesting stuff in this thread that hasn't yet descended to the usual crazy rants that get associated with any discussions around green issues.
Genuine question based around the OP's original question & the subsequent answers. If the 9mpg Bentley emits less harmful emissions than the 30mpg Fiesta how is that measured? I understand the bit about what comes out the tail pipe being "cleaner" due to the tech in the engine but how does the fact it's still burning 3 times as much fossil fuel feature in the equation?
Surely the consumption of 3 times the amount of something to travel the same distance can't be better or does the way in which it consumes it far outweigh what it consumes?
Is it parts of something per amount of fuel burnt? Trying to do some googling and it's all coming up a bit vague.
Which for example have a car checker which has the unhelpful scale of "extremely low" to "high"
https://www.which.co.uk/reviews/new-and-used-cars/...
Genuine question based around the OP's original question & the subsequent answers. If the 9mpg Bentley emits less harmful emissions than the 30mpg Fiesta how is that measured? I understand the bit about what comes out the tail pipe being "cleaner" due to the tech in the engine but how does the fact it's still burning 3 times as much fossil fuel feature in the equation?
Surely the consumption of 3 times the amount of something to travel the same distance can't be better or does the way in which it consumes it far outweigh what it consumes?
Is it parts of something per amount of fuel burnt? Trying to do some googling and it's all coming up a bit vague.
Which for example have a car checker which has the unhelpful scale of "extremely low" to "high"
https://www.which.co.uk/reviews/new-and-used-cars/...
It depends which problem you're concerned about. If you are worried only about local air quality, then as long as the thing is burning sufficiently cleanly, you don't care how much fuel it is burning. If you are worried only about climate change, you don't care much how clean it is, it's the total amount of fuel being burnt.
Simpo Two said:
RobXjcoupe said:
It’s the type of emission not the amount of emissions. The amount of emissions is penalised with a higher rate of road tax
That's just CO2 isn't it? Kgs per wotsit.ULEZ is based on NOx and PM, hence why diesels are disproportionately affected as they produce more of both than gasoline engines (though DI has made this less true - hence the need for GPFs now).
It’s the reason why my 2007 350Z, being Euro4 compliant, can go into central London and not pay the ULEZ fine. It’s low NOx and PM. On the flip side, I get stung each year for VED.
My dads 2010 320D on the other hand is fairly cheap on VED as diesels produce less CO2, but has to stump up £12.50 to enter London as his is only Euro5 compliant because it kicks out too much NOx and PM.
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