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WLTP, NEDC results

Old 03-25-2019, 05:21 PM
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Join Date: Mar 2019
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Default WLTP, NEDC results

Hi. I hope you are all doing well. This is my first post.

I would like to know if it's possible to see a complete list/database of the results of NEDC and/or WLTP testing for all cars. Does anyone know? In one place, the results for all cars for CO2, CO, NO, particulates and unburnt hydrocarbons with an amount per mile or per litre for each of those or however they measure it. Or whatever other pollutants they test for. I am not interested in CO2 only results, that is a nice to have, but it's easy to work out roughly from the petrol efficiency (mpg or km/l). I am more interested in the other pollutants.

If it's not possible to see the full list of results for every car, is there a way to find out the results of CO, NO, particulates and unburnt hydrocarbons for a specific model.

I currently have a Honda CR-V so would be interested with that. I would also be interested in a typical, average value for petrol and separately for diesel cars for each of those pollutants so I have a reference point.

I may buy a Prius or another hybrid. Here in Chile the others that I know of are the Honda Civic Hybrid, the Lexus CT200h, Lexus 450 hybrid, and the Kia Optima. I would like to see the values for all those cars as part of the purchase decision. We will likely be buying a car made in 2012-2016 so would need to see the results for cars made in those years, not just new ones. However, if that's not possible, I'd still like to see the 2017-2019 results for similar models as a guide.

I saw one report on the UK Which site that the Prius has very low emissions of some pollutants (I think CO and maybe some others) - like 90% or more less than a regular petrol car per mile. This is interesting, because a Prius can only cut CO2 per mile by maybe 40-50% compared to a regular petrol car, so I imagined the same 40%-50% might be true for other pollutants, but it seem that this is not the case at all. I am not sure why that is. I am partly curious to know if hybrids in general produce less non CO2 pollutants per gallon/litre of petrol burnt than regular petrol cars as a general rule, or whether it was just true for the hybrid.
Old 03-25-2019, 06:22 PM
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Location: Mesa, AZ
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Default Re: WLTP, NEDC results


Avoid 2003-2011 Honda Civic Hybrid.
Avoid Lexus GS450h - performance car - very poor economy (RX450h SUV is fine, but it's an SUV - lower economy)

You are focusing on unimportant details and are falling victim to rumor.

mpg or km/l or L/100km dictates CO2 emissions. Period. Prius getting 40 mpg doesn't produce any less CO2 than an Honda Fit or Chevy Cruze getting 40mpg. Period.

Car A that gets 40mpg will produce EXACTLY the same CO2 per mile as Car B that gets 40 mpg when using the same fuel. Period.

The "other pollutants" are of minimal concern in properly tuned vehicles with the proper emissions equipment. CO, NOX and particulates are all very low. Making a purchasing decision on that basis is like finding the best place to read by moonlight - not useful.

Diesel produces a LOT of particulates. Period. There are newer systems in place that help minimize it, but it is very high compared to petrol. Diesel fuel has higher energy content and higher thermodynamic efficiency, so mpg will be higher and less CO2 produced per mile.

You should base your decision on the best balance of (in order of importance):
  1. Local support (you WILL have problems with it, and they will be costly)
  2. Acceptable cost
  3. Acceptable fuel economy
The other details are just noise. They depend on the quality of your Chile fuel and the fitted equipment of the vehicles produced FOR your country. If you don't find this data available for the exact models FOR Chile burning Chile fuel, then you have no data.

Buy the most fuel efficient vehicle and be GUARANTEED that you will have the lowest CO2/mile and less of the other pollutants per mile.
Old 03-26-2019, 10:03 AM
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Default Re: WLTP, NEDC results

2003-2011 Honda Civic Hybrids are terrible. Nothing but trouble. Switched to Lithium batteries in 2012 and reliability went way up. Have the occasional very expensive inverter failure.

USEFUL information upon which you could make a decision doesn't exist.

Use of analogous data for a different region could be rendered completely wrong and even reversed depending on the emmissions equipment installed and the quality of your fuel. CO2 is directly proportional to the amount fuel burned. The amount of fuel burned also dictates the additional amount of trace pollutants produced.

If you produce less CO2, you produce less trace pollutants. If the car is fitted with proper emissions control equipment (evaporative and catalytic), those trace pollutants will be as low as possible.

If you are concerned about particulates, then you simply take diesels off the table. The amount of particulates in petrol depends heavily on the quality of the petrol itself, which is region and producer dependent. Sulphur and other impurities have a STRONG influence on the cleanliness of burn.

Concerning the smell out of tailpipes, maybe don't get so close. PLUS, what you're smelling are IDLE pollutants. Controlling/regulating pollutants at idle is extremely difficult (impossible by any practical measure) because no power is being extracted from the heat and you will get hydrocarbons out the tailpipe (unburned fuel). Once the car is under power and moving, those smelly pollutants are minimized because the fuel burn/power extraction process is inherently cleaner.

Source and context of data/research matter. Given that > 80% of all americans live in urban areas, that's 250 million that live in urban areas. If 150 million Americans live in areas that don't meet federal air quality standards, 163 million Americans DO live in areas that meet and 100 million of those ARE in urban areas. Urban areas struggle to meet air quality standards due to population and pollution density. It shouldn't be the driving force. 100% of fossil fuel burning power plants fail to meet those federal air quality standards at the smokestac... Furthermore, there are NO references for those specific claims. In many cases, data presented like that are less alarming when you know the details. It might mean that quality standards were violated for only 1 day, 1 week, 1 month, etc. It's a boiled down statement that may be true, but the context is not presented, an one can't draw a conclusion.

Here's an example:


(bottom right bar chart)

In 2017 of the 35 major U.S. cities monitored, there were 729 reported days where one or more of those 35 cities violated the standards... 35 cities, 365 days per year = 12,775 "city-days" in a year. That means that 729/12775 = 5.7%, i.e., on average, the U.S. cities failed to meet federal air quality standards 5.7% of the time. Conversely, the 35 cities met the standards 94.3% of the time ON AVERAGE.

That paints a VERY different picture than, "150 million Americans live in an area that fails to meet air quality standards."
Old 03-26-2019, 05:47 PM
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Join Date: Mar 2019
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Default Re: WLTP, NEDC results

Thanks again for your help.

I see my first reply has disappeared, perhaps deleted by the moderators because of the links. But the main focus of it was that air pollutants from cars (excluding CO2) and climate change from cars (from CO2) both cause substantial deaths on a similar order of magnitude.

Just to clarify, it's the 2012+ Hondas have the inverter failure you mentioned (not the 2003-2011 ones). Right?

When I go jogging cars going at a steady speed of typically 30mph-50mph blast smelly unhealthy pollution over me that sometimes makes me cough. I actually cover my mouth with my hands when trucks and the largest cars go past. So, I'm not convinced it's just idling.

Your comment "The amount of fuel burned also dictates the additional amount of trace pollutants produced" is in disagreement with the tests I saw by the Which consumer organization in the UK: "We found there is no strong link between MPG and NO2/NOx – just because you have low fuel bills, it doesn't mean you have a clean car. It's not just about diesel cars and NOx. Petrol cars also produce large amounts of CO. We’ve even found hybrids that produce high levels of toxic emissions." They actually run tests and make measurements themselves.

Petrol cars do certainly produce less NOx (i.e. NO or NO2) on average, but not always. Emissions Analytics' CEO has said that: "If you take the cleanest 10% of diesels and the dirtiest 10% of petrol cars, then actually the petrol models will have double the NOx emissions of the diesel ones". The Which report found a similar result. For example, it found that the Mercedes Benz SL produced more NOx than many diesels and would have failed the standards for diesels.

That's why I am looking for data by model. Which reports the Subaru Forrester as producing 2.0 g/km of NOx but the BMW 2 series as being 0.01 g/km. (Note they did some real world driving with a portable emissions device attached, incase they had a cheat device, and therefore concluded that there was no cheat device.) They report a similar massive range for carbon monoxide (CO) - for which Toyota Prius is the lowest, producing 300 times less than the Subaru Outback. That's why there's a need for data by model. The problem is Which's own tests have just published for some models, not including most of the ones I want to see.

I don't agree that moving to a different country will change things by enough to make the data useless, especially when some cars produce 200 or 300 more times of a pollutant than another. My guess is that slight variations in the quality of petrol would not change the emissions by anywhere near that much.
Old 04-02-2019, 04:39 AM
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Join Date: Mar 2019
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Default Re: WLTP, NEDC results

Hope you don't mind me bumping this just to see if anyone has an answer to the question:

I am looking for measured CO, NO/NO2 (NOX), particulates and unburnt hydrocarbons by car model.

Relevant articles about air pollution below:
The first is from today. The second is from earlier this year.
Old 04-08-2019, 08:24 AM
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Join Date: Mar 2019
Posts: 5
Default Re: WLTP, NEDC results

Did some more research. If you google Equa Index you can find NOX and CO results from Emissions Analytics.
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