Mileage so low that EV would be worse for environment?

[Richard-D]

Just a thought...

My wife's car does a commute of about 20 miles (round trip) each day. That's ideal for changing to electric and when they drop to a reasonable price we probably will.

Mine however (big diesel SUV) sits on the driveway for >99% of the time and gets used very sparingly. It probably does about 4000 miles a year at most. At some point EVs are going to come that are capable of replacing it, which is great. When they do though, would it actually be better for the environment for me to keep an older vehicle running than buy a new, much cleaner vehicle? Presumably there is a point where the environmental costs of producing the new vehicle outweigh the benefits (when the usage is so low).

[jay2000]

It boils down to how much you want to spend on your motors. Saving you money or having the latest and greatest. Some would say take a bike for short mileage but thats not normally practical. Each people's circumstances will be different. Being such low mileage usage, you are privy to a large selection of used and new EVs. Good luck.

[NugentS]

Also consider - does your big diesel have a DPF
If yes then if you are doing only short journeys then you may well be gambling with the DPF.
If however you do a monthly long journey, and don't do short journeys then fine. Basically the DPF needs to get a chance to regen otherwise it clogs up

[Richard-D]

jay2000 said:

It boils down to how much you want to spend on your motors. Saving you money or having the latest and greatest. Some would say take a bike for short mileage but thats not normally practical. Each people's circumstances will be different. Being such low mileage usage, you are privy to a large selection of used and new EVs. Good luck.

I don't see that it boils down to that at all. I've intentionally left cost out of the question.

[Richard-D]

NugentS said:

Also consider - does your big diesel have a DPF
If yes then if you are doing only short journeys then you may well be gambling with the DPF.
If however you do a monthly long journey, and don't do short journeys then fine. Basically the DPF needs to get a chance to regen otherwise it clogs up

No it doesn't, EU4 with cats but no DPF.

My wife's car is a diesel though and has had no problems despite its low mileage usage for the past 5 years. Mine doesn't tend to do really short journeys, most things I buy are within walking distance.

Edited by Richard-D on Monday 30th November 11:43

[carlove]

NugentS said:

Also consider - does your big diesel have a DPF
If yes then if you are doing only short journeys then you may well be gambling with the DPF.
If however you do a monthly long journey, and don't do short journeys then fine. Basically the DPF needs to get a chance to regen otherwise it clogs up

My diesel has gone from doing 25000 miles a year to not many miles doing short trips due to Covid.

I had a DPF full warning come up a few weeks ago so drove quickly up and down the bypass a couple of times and it cleared. I’m now taking it up and down the motorway (as busy as ever) once a week just to let it regen and keep working properly. Could do without a large car repair at the moment so took the risk with breaking lockdown rules.

My mileage will likely go back up again once things are back to normal (if they ever are) so no point trading in.

[Ardennes92]

Awhile ago I read a few articles (can’t find at moment) that quoted 150k miles as the cut off where you expelled more from the exhaust than the manufacturer put into manufacturing the vehicle, so building another new vehicle doesn’t make sense to me. Even more difficult to find current and honest/independent figures.

[jjwilde]

It will always be better for the local environment to have the EV.

One of my neighbours has an old diesel people carrier thing and they hardly ever use it, whenever they do you can taste the diesel in the air. Horrible thing. I also just noticed that somehow it's not been MOT'ed for 3 years!!

[FunkyNige]

carlove said:

My diesel has gone from doing 25000 miles a year to not many miles doing short trips due to Covid.

I had a DPF full warning come up a few weeks ago so drove quickly up and down the bypass a couple of times and it cleared. I’m now taking it up and down the motorway (as busy as ever) once a week just to let it regen and keep working properly. Could do without a large car repair at the moment so took the risk with breaking lockdown rules.

My mileage will likely go back up again once things are back to normal (if they ever are) so no point trading in.

Off topic, but I was chatting to a Land Rover mechanic when he came round to do a recall software update on my car, I've now got a petrol because I wasn't doing the mileage to justify a diesel and mentioned in my old diesel I would blast up and down the bypass for 10 minutes to clear the DPF, he said that would do nothing and it needs something like 20 minutes constant to clear it and in the Land Rovers they've found 50mph is best.

[Richard-D]

jjwilde said:

It will always be better for the local environment to have the EV.

One of my neighbours has an old diesel people carrier thing and they hardly ever use it, whenever they do you can taste the diesel in the air. Horrible thing. I also just noticed that somehow it's not been MOT'ed for 3 years!!

I think this thread may require a more rational response than you can muster Rob.

[DuncanM23]

Ardennes92 said:

Awhile ago I read a few articles (can’t find at moment) that quoted 150k miles as the cut off where you expelled more from the exhaust than the manufacturer put into manufacturing the vehicle, so building another new vehicle doesn’t make sense to me. Even more difficult to find current and honest/independent figures.

Finding independent accurate figures is going to be impossible, because you'd need so much data from the manufacturer, but I think your number is significantly out.
VW released a study a couple of years ago with production and use data for an e-Golf and a diesel Golf showing a crossover point (where the e-Golf is less polluting) at around 100,000 miles, using average European electricity CO2 (from 2017). You can see some of their math here: https://www.volkswagenag.com/en/news/stories/2019/...

Their number for the crossover point where the exhaust emissions exceed that of production at under 50,000 miles, and that's a relatively efficient car (and using their mpg data no doubt). It also shows production only generating about 20% of the lifetime emissions of the vehicle, so if you have a car that is significantly less efficient than a 2019 Golf diesel (like a real world Golf Diesel!) that production figure is going to be significantly smaller.

[Pica-Pica]

DuncanM23 said:

Ardennes92 said:

Awhile ago I read a few articles (can’t find at moment) that quoted 150k miles as the cut off where you expelled more from the exhaust than the manufacturer put into manufacturing the vehicle, so building another new vehicle doesn’t make sense to me. Even more difficult to find current and honest/independent figures.

Finding independent accurate figures is going to be impossible, because you'd need so much data from the manufacturer, but I think your number is significantly out.
VW released a study a couple of years ago with production and use data for an e-Golf and a diesel Golf showing a crossover point (where the e-Golf is less polluting) at around 100,000 miles, using average European electricity CO2 (from 2017). You can see some of their math here: https://www.volkswagenag.com/en/news/stories/2019/...

Their number for the crossover point where the exhaust emissions exceed that of production at under 50,000 miles, and that's a relatively efficient car (and using their mpg data no doubt). It also shows production only generating about 20% of the lifetime emissions of the vehicle, so if you have a car that is significantly less efficient than a 2019 Golf diesel (like a real world Golf Diesel!) that production figure is going to be significantly smaller.

I cant see much about non-tailpipe emissions. Some cars still have a ‘zero-emissions’ badge on them, rather than ‘zero tailpipe emissions’.

[Richard-D]

Ardennes92 said:

Awhile ago I read a few articles (can’t find at moment) that quoted 150k miles as the cut off where you expelled more from the exhaust than the manufacturer put into manufacturing the vehicle, so building another new vehicle doesn’t make sense to me. Even more difficult to find current and honest/independent figures.

It's such a tricky bit of maths i'm not even sure how far you'd go with it. Do you take in the lifespan of a vehicle battery? Does that make the lifespan of an electric vehicle less than that of an ICE vehicle?

[Knock_knock]

The Union of Concerned Scientists had this to say - in 2015 - from https://www.ucsusa.org/sites/default/files/attach/...

"Global warming emissions occur when manufacturing any
vehicle, regardless of its power source, but BEV production
results in higher emissions than the making of gasoline cars—
mostly due to the materials and fabrication of the BEV lithium-ion
battery. Under the average U.S. electricity grid mix, we
found that producing a midsize, midrange (84 miles per
charge) BEV typically adds a little over 1 ton of emissions to
the total manufacturing emissions, resulting in 15 percent
greater emissions than in manufacturing a similar gasoline
vehicle. However, replacing gasoline use with electricity reduces
overall emissions by 51 percent over the life of the car.
A full-size long-range (265 miles per charge) BEV, with
its larger battery, adds about six tons of emissions, which increases
manufacturing emissions by 68 percent over the gasoline version.
But this electric vehicle results in 53 percent lower overall emissions
compared with a similar gasoline vehicle.

In other words, the extra emissions associated with electric vehicle
production are rapidly negated by reduced emissions from driving.
Comparing an average midsize midrange BEV with an average
midsize gasoline-powered car, it takes just 4,900 miles of driving to
“pay back”—i.e., offset—the extra global warming emissions from
producing the BEV. Similarly, it takes 19,000 miles with the full-size
long-range BEV compared with a similar gasoline car. Based on
typical usages of these vehicles, this amounts to about six months’
driving for the midsize midrange BEV and 16 months for the full-size
long-range BEV. "

So in this case if your SUV has done more than 20,000 miles it's probably still "better" for the environment to replace

[Richard-D]

DuncanM23 said:

Ardennes92 said:

Awhile ago I read a few articles (can’t find at moment) that quoted 150k miles as the cut off where you expelled more from the exhaust than the manufacturer put into manufacturing the vehicle, so building another new vehicle doesn’t make sense to me. Even more difficult to find current and honest/independent figures.

Finding independent accurate figures is going to be impossible, because you'd need so much data from the manufacturer, but I think your number is significantly out.
VW released a study a couple of years ago with production and use data for an e-Golf and a diesel Golf showing a crossover point (where the e-Golf is less polluting) at around 100,000 miles, using average European electricity CO2 (from 2017). You can see some of their math here: https://www.volkswagenag.com/en/news/stories/2019/...

Their number for the crossover point where the exhaust emissions exceed that of production at under 50,000 miles, and that's a relatively efficient car (and using their mpg data no doubt). It also shows production only generating about 20% of the lifetime emissions of the vehicle, so if you have a car that is significantly less efficient than a 2019 Golf diesel (like a real world Golf Diesel!) that production figure is going to be significantly smaller.

That suggests to me that it could potentially be less polluting to buy a new ICE car for some usage types. That wasn't actually what I was asking but is interesting that it could be the case as I hadn't considered that.

I like the comment about the Golf Diesel As you say, it's already difficult enough to compare without lying car manufacturers being involved.

[Heres Johnny]

Keep your diesel. Running a car until it dies has got to be the best for the environment; Anything that encourages another car to be built is a backward step.

People need to drive less irrespective of how a car is powered, and all the "mine runs on solar" are missing the point too, that energy could be put into the grid and used for other purposes. There is no real benefit in "renewable energy tariff". Its just a commercial model where they buy from a wind farm what would would otherwise supply to the grid. It might encourage renewable production a bit, but there's much bigger drivers for that going on. But plenty of EV owners happily drive more than they ever have before thinking its guilt free driving because it doesn't burn fossil fuel. Sorry, but its really not very environmentally friendly at all, its just better than doing the mileage in an ICE.

If you take a local mindset that you're anti diesel because you can smell it once a week when it fires up, are you really thinking green or are you just thinking nimby?

[Richard-D]

Knock_knock said:

The Union of Concerned Scientists had this to say - in 2015 - from https://www.ucsusa.org/sites/default/files/attach/...

"Global warming emissions occur when manufacturing any
vehicle, regardless of its power source, but BEV production
results in higher emissions than the making of gasoline cars—
mostly due to the materials and fabrication of the BEV lithium-ion
battery. Under the average U.S. electricity grid mix, we
found that producing a midsize, midrange (84 miles per
charge) BEV typically adds a little over 1 ton of emissions to
the total manufacturing emissions, resulting in 15 percent
greater emissions than in manufacturing a similar gasoline
vehicle. However, replacing gasoline use with electricity reduces
overall emissions by 51 percent over the life of the car.
A full-size long-range (265 miles per charge) BEV, with
its larger battery, adds about six tons of emissions, which increases
manufacturing emissions by 68 percent over the gasoline version.
But this electric vehicle results in 53 percent lower overall emissions
compared with a similar gasoline vehicle.

In other words, the extra emissions associated with electric vehicle
production are rapidly negated by reduced emissions from driving.
Comparing an average midsize midrange BEV with an average
midsize gasoline-powered car, it takes just 4,900 miles of driving to
“pay back”—i.e., offset—the extra global warming emissions from
producing the BEV. Similarly, it takes 19,000 miles with the full-size
long-range BEV compared with a similar gasoline car. Based on
typical usages of these vehicles, this amounts to about six months’
driving for the midsize midrange BEV and 16 months for the full-size
long-range BEV. "

So in this case if your SUV has done more than 20,000 miles it's probably still "better" for the environment to replace

Thanks for that post, that's probably the closest to describing how to go about starting to make a comparison. I'll have to read that a couple of times and have a good think before I can work out how to apply it.

I think your statement at the end is a little odd though. Surely any mileage it's already done is irrelevant, that's already happened and we can't change it. Similarly with initial production too, we can't change that. I may have misunderstood what you meant though.

[Richard-D]

Heres Johnny said:

Keep your diesel. Running a car until it dies has got to be the best for the environment; Anything that encourages another car to be built is a backward step.

People need to drive less irrespective of how a car is powered, and all the "mine runs on solar" are missing the point too, that energy could be put into the grid and used for other purposes. There is no real benefit in "renewable energy tariff". Its just a commercial model where they buy from a wind farm what would would otherwise supply to the grid. It might encourage renewable production a bit, but there's much bigger drivers for that going on. But plenty of EV owners happily drive more than they ever have before thinking its guilt free driving because it doesn't burn fossil fuel. Sorry, but its really not very environmentally friendly at all, its just better than doing the mileage in an ICE.

If you take a local mindset that you're anti diesel because you can smell it once a week when it fires up, are you really thinking green or are you just thinking nimby?

That's my gut feeling on the subject too. I suspect that I'm far less damaging to the environment than most. I always walk to the shops and look after everything I own to get the longest lifespan from it, planted a couple of acres of woodland a few years ago etc etc. I do know however that gut feelings tend to be very biased so am trying not to rely on just that.

[Knock_knock]

Richard-D said:

Thanks for that post, that's probably the closest to describing how to go about starting to make a comparison. I'll have to read that a couple of times and have a good think before I can work out how to apply it.

I think your statement at the end is a little odd though. Surely any mileage it's already done is irrelevant, that's already happened and we can't change it. Similarly with initial production too, we can't change that. I may have misunderstood what you meant though.

Sorry, it could probably have done with being more clearly put

On page 3 of that report is a chart which shows that for the ICE car the production emissions make up about 12% of the total lifetime emissions, on an assumed lifetime of 135,000 miles for a mid-size gasoline car.

So if it is the actual driving which contributes the lions share of emissions then it seems that you probably don't need to be driving all that miles before the production emissions of a BEV would off-set them.

On this example it suggests that by the time the mid-size gasoline car has driven 66,000 miles it will have produces the same emissions as the BEV will at 135,000. For the full-size gasoline car the point is 84,000 miles to reach parity with a long-range BEV doing 179,000.

However, these calculations have changed a lot since 2015 - the USA grid has become generally less emissive across the board and battery production methods have benefitted from both this reduction (if made in USA - I think Tesla claim to be carbon neutral on batteries?) plus a further reduction in emissions due to changed processes etc.

USC have put out a few papers around these changes but haven't rolled it all together into an updated comparative publication that I've seen.

So what I was trying to say, unsuccessfully in a single sentence, is there is a point where every further mile driven in an existing ICE vehicle is more polluting in total than building and running a new BEV. The figure of 20,000 miles is probably too low to be fair, having looked at these figures again, but it's probably no higher than 40,000 miles given the UK electrical grid.

[DuncanM23]

Richard-D said:

Ardennes92 said:

Awhile ago I read a few articles (can’t find at moment) that quoted 150k miles as the cut off where you expelled more from the exhaust than the manufacturer put into manufacturing the vehicle, so building another new vehicle doesn’t make sense to me. Even more difficult to find current and honest/independent figures.

It's such a tricky bit of maths i'm not even sure how far you'd go with it. Do you take in the lifespan of a vehicle battery? Does that make the lifespan of an electric vehicle less than that of an ICE vehicle?

Given the fact that EV batteries are usually re-used for home energy storage (or in similar commercial facilities), does that mean that the EV has a longer lifespan? Sure, in 10 years time (or whatever) the car might have been recycled, but the battery will still be doing something useful.