Comment on SUVs emit more climate damaging gas than older cars do, study finds
Kecessa@sh.itjust.works 1 year ago
If looking at carbon emissions only… Well, no shit? No need for a study to know that, it’s purely based on fuel economy. Look at other types of emissions though and a 2023 SUV with a brand new catalytic converter will be much better than a 10 years old car.
paintbucketholder@lemmy.world 1 year ago
How so? Cars have to pass emissions tests, and ten year old cars have to pass them, too.
Also: what significant improvements in filtering out “other types of emissions” have there been made in consumer vehicles in the last 10 years, and what “other types of emissions” are those?
Kecessa@sh.itjust.works 1 year ago
en.m.wikipedia.org/…/European_emission_standards
A 10 years old car would fall under Euro 5b standards instead of Euro 6d, there’s also a level of tolerance when a car gets tested so it might have beat the standard by a good meeting when it was new, it still passes the test 10 years later because it’s still under what’s allowed but not as good as it was when new.
CO2 emissions don’t get filtered by the anti emissions equipment, they’re the by-product of combining the CO emissions with unburnt hydrocarbons, it’s 100% based on how much fuel is burned by the vehicle and that’s it. Anti pollution systems do reduce NOx emissions by splitting it and Euro 6 tolerates less than half the NOx emissions that Euro 5 does while also reducing the tolerance for HC+NOx (talking about diesel here, since the standards were the same Euro 5 to Euro 6 for petrol vehicles).
Euro 6 also introduced particle emissions for petrol cars, which only existed for diesel vehicles under Euro 5. Euro 7 is coming in 2025 and will add NH3 and brake pads particles into the mix.
paintbucketholder@lemmy.world 1 year ago
Right.
So no changes between 2013 and 2023 standards for petrol cars. No new technology to reduce harmful emissions either.
So there’s no actual argument in favor of a new SUV over a 10 year old car, outside of marginal degradation of the catalytic converter or degradation of the combustion process - most of which should still be caught in emissions tests.
And even then, properly maintaining the car, replacing the catalytic converter or even replacing the 10 year old car with a new car of the same size instead of upsizing to an SUV would all be better for the environment than buying a new SUV.
Kecessa@sh.itjust.works 1 year ago
I never said there’s no new technology because there is and improvements to existing technology too, the proof being that the standards become more strict as time goes by and manufacturers need to plan ahead for it.
I said that just looking at carbon emissions is ridiculous as it’s a simple matter of how much fuel is burnt, it either comes out at CO or CO2 and both are bad, that study could be resumed by saying “Carbon emissions are worse in vehicles with worse fuel economy.” For this reason emission equipment improvements are concentrated on other emissions as we’re already handling CO emissions the best way possible with what’s feasible in a vehicle. Fuel economy improvement is the way we reduce carbon emissions and that’s also improving, an example is that my ICE car develops more power from a smaller, more efficient engine than the previous year model so its fuel economy is comparable to smaller cars from 10 years ago, its emissions are lower, but the driving experience is still better.
This is a European study so diesel vehicles are much more common and the SUV also beats the standards by a wide enough margin that the emission equipment won’t need to be replaced in 10 years. I’m just pointing out that if they only studied carbon emissions then the study is flawed as there are other emissions to look at.
No one replaces a catalytic converter as part of regular maintenance, that’s a thousands of £ job that you do when you fail the emissions test or it becomes clogged. Same thing for all the emissions equipment (O2 sensor, knock sensor, EGR system…) or carbon buildup that prevents the valves from sealing properly/blocks the intake, they’re things that get taken care of only when they fail.