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There may also be a learning issue. Some folk might just be better at anticipating issues and adapting to regen braking, while others might brake harder and later.
With the E Tron you just brake as normal it will decide if the discs are needed.
I almost never use the brakes on my model 3, it really is rare, maybe once or twice in the average mixed journey. It takes 5 minutes in an EV with regen set to high for you to click and think, 'one pedal driving is SO much better'. You could quite easily commute daily and never brake. Even using the accelerator downhill to maintain speed the car is just balancing coasting and regen.
You WILL almost sail straight over the first junction when you get back in an ICE car. Luckily the 33" mud tyres on the hilux act like a regen system
Had a quick flick through the OECD report on vehicle particulates. Not got time to read it all at the moment but this paragraph stuck out:
Several estimates of the impact of RBS [Regenerative braking systems] on brake wear PM emissions exist in literature.
The Platform for Electro-Mobility (2016[13]) claims that RBS reduce brake wear by 25-50%. Van Zeebroek and De Ceuster (2013[7]) assume that regenerative braking should reduce the PM emissions associated with brake wear by 50%. Timmers and Achten (2016[9]) assume a zero brake wear emissions from RBS-equipped vehicles, and Barlow (2014[14]) also suggests that regenerative braking produces virtually no brake wear.
Hooftman et al. (2016[10]) state that EVs require about two-thirds (66%) less braking activity than ICEVs due to RBS. Their analysis is based on the service times of brake pads on Teslas, BMW i3s, and Nissan Leafs, which demonstrates that on average, the brake pads of these EVs last roughly two-thirds longer than those on diesel/petrol vehicles. They note that this outweighs the additional wear due to the vehicle’s mass.
Ligterink et al. (2014[15]) assume regenerative braking reduces wear by up to 95%. Del Duce et al. (2016[16]) report that brake wear emissions fall by 80% for EVs, based on a report by Althaus and Gauch (2010[17]). Nopmongcol et al. (2017[18]) estimated a 25% reduction of brake wear.
VERY mixed numbers and assumptions there, but they generally seem to agree that regenerative braking helps.
Non-exhaust particles from road traffic are certainly a bigger source of pollution in the UK than tailpipe emissions and, as traffic volumes continue to grow, it is worrying that there is no regulation in place to govern NEE particles," comments Professor Harrison. "We have a UK target of switching entirely to electric vehicles – in terms of new sales – by 2035. The aim of this is to reduce CO2 and air pollutant emissions, but there is currently a debate around electric and internal combustion vehicles regarding NEE particles. Battery-driven cars are heavier but generate power under braking and should emit fewer particles as regenerative braking does not rely on frictional wear of brake materials."
https.://www.birmingham.ac.uk/research/quest/sustainable-environments/brake-dust-and-brown-carbon.aspx
Likewise I can’t find anything that says they use more. Just that they still do and they feel needs addressed.
Drac
With the E Tron you just brake as normal it will decide if the discs are needed.
Agreed. Except that if you brake late will it not decide to use more disc (not necessarily less regen)?
I also agree I think that regen braking will help (I can’t see how it wouldn’t) my point is that good driving will help - both in minimising braking and maximising the proportion of braking that is regenerative.
On might EVs emit more particulate...
https://www.oecd-ilibrary.org/sites/4a4dc6ca-en/index.html?itemId=/content/publication/4a4dc6ca-en
Note that the also state it’s the PM2.5 they are most worried about.
Electric vehicles are estimated to emit 5-19% less PM10 from non-exhaust sources per kilometre than internal combustion engine vehicles (ICEVs) across vehicle classes. However, EVs do not necessarily emit less PM2.5 than ICEVs. Although lightweight EVs emit an estimated 11-13% less PM2.5 than ICEV equivalents, heavier weight EVs emit an estimated 3-8% more PM2.5 than ICEVs. In the absence of targeted policies to reduce non-exhaust emissions, consumer preferences for greater autonomy and larger vehicle size could therefore drive an increase in PM2.5 emissions in future years with the uptake of heavier EVs.
Agreed. Except that if you brake late will it not decide to use more disc (not necessarily less regen)?
I also agree I think that regen braking will help (I can’t see how it wouldn’t) my point is that good driving will help – both in minimising braking and maximising the proportion of braking that is regenerative.
Of course it will they weigh over 2 tons but it’s incredible how quick they stop. Yes bad driving will but that’s the same for combustion engines too.
1. There are capacity issues on a local level especially in old cities and at a generation level. There are some ways of managing things e.g. charging overnight when other power demand is low but overall lots of infrastructure work does need to be done facilitate widespread use of EVs.
2. In theory - charging posts near the kerb would service electric charging for sites that don't have off road parking.
3/4. Although some people pretend otherwise, people don't have any special rights to the bit of public road outside their house - with the exception to areas of dropped kerb for driveways. Spaces are reserved only if they get an individual designated permit bay, or can defacto be reserved if they have a disabled bay.
You can designate parking areas for electric vehicles which would seem like a reasonable way to deal with areas serviced by charging facilities.
charging overnight when other power demand is low
Remember that only works with the present generation fleet. If we move to a more heavily renewable fleet then we may need either significant fixed storage or potentially more network. However a bit of legislation about workplace and home charging would pretty much ensure the network is ok. The network companies are not overly concerned. Heat is more concerning.
charging posts near the kerb would service electric charging
Remember that many councils just finished moving street lights away from kerb edges for safety reasons. The splutter and swear at me when I make suggestions like that.
@Drac - I don’t think we’re disagreeing.
On might EVs emit more particulate…
Yeah it's a bit of an odd paragraph that: "light EVs emit less PM2.5 than ICE, but heavy EVs emit more., and in the future people might want heavier EVs."
Well yeah, okay, but they might want heavier ICE vehicles too. 🤷♂️
Also that is non-exhaust particulates, which kind of ignores that the ICE vehicles have exhausts.
Section 3 of the report is better for some actual detail.
I don’t think we’re disagreeing.
No, I don’t this we are any a Graham points out it’s a bit unclear as it mentions heavier EV use more than average but mentions nothing of ICE. I drive a Kodiaq at work which is the same size and pretty much a Q7 so a good comparison to my E tron. It needs a lot to stop it too as it’s a monster but only have discs and be regen. I wonder if the Cooler brake temps that some EV pads work at will also reduce the particles. It’s something needs addressed but it not a reason to stop EVs coming in as planned.
Well yeah, okay, but they might want heavier ICE vehicles too.
Not sure how relevant it is to your specific point but isn't one part of the non exhaust particle problem that most EVs are about a quarter to a third heavier like for like so naturally are going to be relatively hard on tyres and road surfaces (all else being reasonably equal).
Of course we have this ghastly habit at a societal level of going ever bigger with our cars - Range Rover culture it's not just the size either it's the power outputs and performance. I am guilty in the sense that I'm currently running an MPV because I was trying not to buy a trailer for camping trips (I now have an MPV and a trailer 🙄).
Next car is coming down in size and I'm hoping by then an EV or at least hybrid at mainstream prices, with a 750kg towing capacity and 75kg nose weight and the ability to do 200 miles fully loaded on a cold day with a trailer will be a reality along with a home charger and a charging network that means I can charge up without hassle on long work trips. What do you reckon for five years time? I reckon it will still be a hybrid to tick the boxes.
Zoé 1475kg + two passengers, say 160kgs dressed = 1635kgs
lightest Clio 1140kg or 1170kg with enough petrol and fluids to get the Zoé's range. + two passengers = 1330kg
305/1330 = 23% heavier.
When magazines compare weights they forget that it takes a fat slob journalist to make the vehicle move and another to film them. And they probably threw a brolly, wellies, a flask a brief case and some other kit in the boot.
You never know you might get a Hammond not a Clarkson 😜
I think the “heavier” EV thing is also a reference to desire for ever bigger ranges meaning ever bigger battery capacities. Now whether than means heavier batteries (with accompanying heavier suspension and bodywork to support them) I don’t know. A Nissan gen4 battery is significantly higher capacity per kilo than a gen2 was. But it is unlikely to lead to lighter cars short term. That said some of the manufacturers I speak to suggest battery capacity will reduce as people realise the benefits of lighter cars and cheaper batteries and start to relax about range anxiety.
Again we’ll see.
Other than that I think we’re all agreeing on the basics, I’ve learnt some things and everyone seems to like the idea of having an EV (albeit with some demands on functionality and price that aren’t quite there yet, and an acceptance that good though they might be no vehicle will be perfect - other than an Orange Five of course 😉)
Orange Five
No call for those anymore. I've gone paperless to save the planet as I can't afford an EV yet. 😉
Now whether than means heavier batteries (with accompanying heavier suspension and bodywork to support them) I don’t know
The latest 52kWh Zoé battery weighs 326kg, the previous 41kWh battery 305kg and the original 23kWh batterie something over 200kg. The capacity : weight ratio of EV batteries is improving constantly. I'm confident EV drive train weight will come down as well. Meanwhile the depolution equipment is driving the weight of ICEs up. I forgot to add the weight of filling the AdBlue tank in my comparision with the Clio earlier.
I forgot to add the weight of filling the AdBlue tank in my comparision with the Clio earlier.
But you did say it was a petrol Clio 🙂