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ajross 2 days ago

To some extent, but not really. Effectiveness of regenerative braking depends on having an extremely large battery that can sink enough current to stop the car. An EV can do that, hybrids at best help the brakes out some. You just can't charge the battery fast enough doing anything but a very slow rolling stop. My model Y can effect a very reasonable stop in traffic without touching the brake pedal except to hold the car at the end.

tbrownaw 2 days ago | parent | next [-]

> Effectiveness of regenerative braking depends on having an extremely large battery that can sink enough current to stop the car. An EV can do that, hybrids at best help the brakes out some. You just can't charge the battery fast enough doing anything but a very slow rolling stop.

This seems a bit exaggerated. Staying regenerative-only does require sticking to about half or so of how fast I could stop, but so far that seems to work fine unless a light turns right in front of me or traffic acts up. Usually it says it gets high 90's or 100%, and it didn't go below 50% even when a stoplight did turn at exactly the wrong time. (2022 Ford Escape non-plug-in hybrid, recently bought used.)

numpad0 2 days ago | parent | next [-]

It's just that Tesla didn't spend skill points on brake blending tech unlockable. Some people confuse it as being a piece of technology of its own.

Every other EVs and HVs assign first half of brake pedal for regen and bottom half for mechanical brakes. Tesla uses bottom half of gas pedal for the same, which eliminates the need to accurately determine the appropriate pedal force that corresponds to intended braking force to be added up with regen to match intended deceleration. Mapping regen to gas is `set_motor_torque(1.25 * gas_pedal - 25);` and that's much simpler.

ARandumGuy 2 days ago | parent | next [-]

This is something that's always baffled me about Teslas. I have a Prius, and regenerative breaking being tied to the break pedal is easy and intuitive. It also means I can easily lift my foot of the gas pedal to coast. IDK it just seems like a much better design to have one "stop" pedal and one "go" pedal, vs one "stop" pedal and one "go/stop" pedal.

ajross 2 days ago | parent [-]

Counterargument is that it's even easier to have only one pedal you use to accelerate and decelerate. Having owned a Prius and a Y, the Tesla is actually smoother to control, by a very significant margin. It's actually a superior way to drive, though it is surprising the first time you see it.

potato3732842 2 days ago | parent | prev [-]

They didn't spend skill points because back when they did it they wanted to lean hard into the "oooh, fancy futuristic EV, look at this cool new driving experience" brand image. Same reason performance cars get loud exhausts even thought they could have quit ones with no decrease in performance.

CraigJPerry 2 days ago | parent | prev | next [-]

100% of possible system capacity to accept regenerative charge on a smaller battery system will be a smaller absolute number than 100% of possible on a larger battery. If you assume everything else is constant, motor, inverter, battery C-rating etc.

Dylan16807 2 days ago | parent | next [-]

I'm not sure what you're arguing here.

Bigger battery is more capacity sure. But their point was that even without a big battery they have enough capacity to get close to maximum effectiveness, contrary to ajross saying that a hybrid's capacity is "not really" effective and "at best" helps "some".

CraigJPerry 2 days ago | parent [-]

just mistaken about maximum effectiveness

braking system = circa 1G of deceleration possible (depending on tyres, coeff of friction, temperature, ... etc etc)

So max effectiveness is unreachable for any regen system on a consumer car hybrid or ev, by a factor of around 6x i believe?

With recognition of the mistaken framing (near max effectiveness) we're back to the larger ev pack has a greater ability to sink current, a larger ability to slow the vehicle than does a smaller battery (obvious considerations about inverter capability, wire gauge etc etc aside)

Dylan16807 2 days ago | parent [-]

I think you might be using a very different definition of "effectiveness" than they are.

Their definition of effectiveness is the percentage of braking force that turns back into electricity and goes into the battery. If your regen system can only do .15G, but 90% of your braking is under .15G, then you'll have about 94% effectiveness by that definition. 94% is not max but it's near max.

It's not about what happens during peak braking, it's about what happens over entire drives.

And when they say "half or so of how fast I could stop" they're underestimating, that's a comparison to a normal but aggressive stop, not pushing the pedal into the ground.

tbrownaw 2 days ago | parent | prev [-]

The manual says it's energy recovered (ie, not something relative to system capacity), and this seems consistent with the other indicator that shows instantaneous braking power with a distinction between what the regenerative system is doing vs what (if anything) the traditional brakes are doing.

CraigJPerry 2 days ago | parent [-]

which car? i think the number you're referring to is relative to electrical system capacity.

It's NOT relevant to overall (tyre, brake system & engine braking & regen braking) braking system performance since that's a dynamic value variable over many factors constantly.

ncruces 2 days ago | parent | prev | next [-]

And when regenerative breaking is not enough, a series hybrid can still apply compression breaking, before resorting to brakes.

ajross 2 days ago | parent | prev [-]

I won't speak to your '22 Escape, but I've driven countless hybrids going back to a '04 Prius and none of them were brake-free in general use. EVs really are.

ARandumGuy 2 days ago | parent [-]

That's because the regenerative braking is applied on the brake pedal, not by lifting up the accelerator. My '14 Prius has a dashboard option to show how much of the regenerative breaking capacity is being used, and it's very easy to stay well below that limit by just gradually slowing down. The friction brakes are only really used when you suddenly stop, which is something you want to avoid anyway.

friendzis 2 days ago | parent | prev | next [-]

> You just can't charge the battery fast enough doing anything but a very slow rolling stop.

And it's not a problem when you get used to regenerative-only braking distances, which are surprisingly long at highway speeds.

It only becomes a problem when idiots thinking "the shorter the distance between first and last car, the smaller the traffic" start cutting you off when you leave enough distance for regenerative braking.

dyselon 2 days ago | parent | prev | next [-]

We finally gave up our Prius after 12 years, and we never changed the brakes once. The brakes were just peeking into the yellow on its last service upgrade. I was really impressed with how well the "normal" hybrid could take advantage of regenerative breaking, honestly.

Helmut10001 2 days ago | parent [-]

I first changed the brakes on my Mitsubishi Space Star (combustion) after 13 years. It is a small car, less than 1000kg, so there is little for the brakes to do. If we produced more percentage of small cars, many environmental risks would be reduced. And btw.: The tires are now 19 years old and still good (less weight, less abrasion!).

jajko 2 days ago | parent | next [-]

That's not OK by any means, you don't have mandatory periodical technical inspections? This would fail immediately in any half-decent country. An example - wife's older Seat has 6 years old winter tires which were given for free when buying it second hand a year ago. Technician just told us even those are beyond acceptable here in Switzerland and we need to change them before next inspection.

Your very old tires makes you a serious threat on the road while completely oblivious about this fact... not cool, please change them if you drive on public roads, if not for you just for the sake of others.

Helmut10001 2 days ago | parent [-]

We are in Germany, which has the highest inspection standards. The tires have passed every inspection. They look like new, but I will still replace them soon, just in case. I am writing this because most people cannot imagine that a 900 kg car puts very little pressure on tires, so they are hardly used.

Tempest1981 2 days ago | parent | prev | next [-]

Rubber degrades with UV exposure, even if the tread depth is ok. Be careful, esp at higher speeds.

lazide 2 days ago | parent | prev | next [-]

Beware of dry rot. Rubber that old is likely not in as good shape as it might appear, and could fail catastrophically in the right conditions.

2 days ago | parent | prev | next [-]
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pkolaczk 2 days ago | parent | prev [-]

Seriously, you should not use tires older than 10 years. They degrade over time.

potato3732842 2 days ago | parent [-]

Time based degradation is mostly a factor of exposure to the sun and the weather.

I just trashed some 15yo Firestones last month, after wearing them completely bald of course.

Swizec 2 days ago | parent | prev | next [-]

> My model Y can effect a very reasonable stop in traffic without touching the brake pedal except to hold the car at the end.

My manual car could do this 20 years ago. My fully ICE motorcycle can do it today.

I know engine braking is cool but it’s not some amazing new thing only EVs can do. Altho granted it only produces heat and noise in petrol vehicles. But it also makes your heart sing so that’s nice

shmoe 2 days ago | parent | next [-]

The difference is neither of those generates gasoline on an ICE vehicle.

tzs 2 days ago | parent [-]

Yup. For example on a round trip today in me EV (2025 Hyundai Kona) on the out here are the stats:

     2 kWh for the drivetrain
   809  Wh regenerated
On the way home:

     2 kWh for the drivetrain
   547  Wh regenerated
For the round trip that's 33% less energy use than if the car did not have regenerative braking.

I'm mostly happy about that but there is one thing that annoys me. 33% is close to how much a kilometer is shorter than a mile (38%).

Why the fuck would I care that these two numbers are that close? It is because of a mystery in the Hyundai app. When you look up the trip details for an EV trip it gives you mileage, duration, and energy use (drivetrain, climate, accessories) and regeneration.

The mileage is substantially less than what the car shows. For example for the aforementioned trip home that trip odometer shows 8.0 miles but the Hyundai app shows 5 miles. The car odometer has the correct distance.

There are two theories to explain this.

1. The app is showing how many miles worth of energy you used rather than your actual trip mileage. All the other data it shows (except for the duration) is energy related. For my 8.0 mile trip I got 3 miles worth of the energy the drivetrain used back via regeneration, so I only actually paid for 5 miles worth of electricity.

Based on the Wh given it should actually be 5.4 miles, but the app only displays integer mileage so 5 it is.

2. It's a botched unit conversion. E.g., the car uploads the data in miles but the expects the data to be in km, so it is doing a conversion. That would turn the 8.0 into 5.0, which would be 5 in the app and so matches what theory #1 predicts.

I've checked several of my trips and they have always happened to have the right amount of regeneration so that the two theories match due to the app only showing an integer mileage.

I did a test today to try to tell them apart. I changed the car's settings to km and took a trip. The idea was if the car had been uploading in miles that would hopefully change it to upload in km, matching the app's expectation, and so the miles shown in the app would match the actual miles of the trip if theory #2 was correct, and show the regeneration corrected miles if theory #1 was correct.

The result was that the app still showed miles consistent with theory #1. So mystery solved, right?

Maybe not. When the car was set to miles everything showed in miles. Speedometer, odometers, efficiency (mi/kWh), speed limits it read from traffic signs, and speed limits it gets from the map data when using navigation on highways.

I expected than when I switched it to km all of those would be in km, and I would not see miles anywhere. Also, I expected that when it saw a speed limit sign that said say 60 it would interpret that as 60 km/hr.

What actually happened is that miles mostly did go away, except on the speedometer it added a smaller mi/hr display under the km/hr display. For the traffic signs it still knew they were in mi/hr and it converted them, so when I got on the freeway as soon as I passed the sign that said 60 the speed limit sign shown on the instrument cluster said 97, and the red dot on the speedometer showing the current limit was placed in the right place.

That suggests that the car knows it is in a country that uses miles, and doesn't just go by whatever the units setting in the setup screen is set to. It could be that in miles countries the car also uploads in miles all the time, and so switching the units setting to km would not change the results if theory #2 was true.

Now my plan is to find a big parking lot that is mostly empty overnight, such at a Walmart or Home Depot or a mall, go there and turn the car off and then back on which starts a new trip, set regeneration to 0 which turns off automatic regeneration on the accelerator so the car only regenerates when you use the brake pedal, and then drive around the parking lot for about 10 miles without using the brakes, then coast to a stop and turn the car off the end the trip.

Then I'll turn it back on, drive home, and check the trip details in the app. If theory #1 is right then the miles in the app should match the odometer miles. If theory #2 is correct the app miles should still be 38% shorter than the odometer miles.

yreg 2 days ago | parent | prev | next [-]

And how often did you engine break with that ICE car when driving around the city? Because I did it only when driving down extreme slopes. It also cannot do a full stop.

With an EV I don't touch breaks unless in situations I fail to/couldn't predict (maybe up to 10% of all speed reductions and even less stops).

Swizec 2 days ago | parent [-]

> And how often did you engine break with that ICE car when driving around the city?

Oh all the time. I used to drive like a typical youth. I've been in USA for 10 years now and still hate driving automatics because they shift into too high a gear and then you have to constantly use the brakes. It's annoying.

stavros 2 days ago | parent | prev | next [-]

I have an ICE car and motorcycle, and an EV. The EV slows down much more quickly when slowing down, to the point where it's a good replacement for the brake, as opposed to the ICE vehicles, where you need to use the brake a lot more. It's not comparable.

Swizec 2 days ago | parent [-]

> The EV slows down much more quickly when slowing down, to the point where it's a good replacement for the brake

Are you comparing to an automatic ICE or a manual?

In my experience of driving EVs their engine braking is sub-par to what I'm used to at least from my motorcycle. Bikes have silly high compression compared to their weight. You def have to be careful about chopping the throttle.

stavros 2 days ago | parent [-]

An automatic, with a manual you can shift down to whatever you want, so there's no standard there, really.

speedgoose 2 days ago | parent | prev [-]

Can’t really compare the engine braking of a Model Y and a ICE vehicle to be honest.

I also like the noise, but it is noise pollution that is very annoying to everyone else.

dotancohen 2 days ago | parent | prev | next [-]

If your Model Y is like my Model 3, then it seamlessly switches to friction breaking below 20 kph. That said, I'm at 110,000 km and the brakes look like new.

jeffbee 2 days ago | parent | prev | next [-]

In normal driving hybrid regen is more than enough to do the job. Just look at the front wheels of any Prius. There are reasons all the Uber drivers choose the Prius.

cyberax 2 days ago | parent | prev | next [-]

You can just waste energy on eddy currents, and then use the car's cooling system to conduct away the heat. After all, dynamic brakes on locomotives just dissipate the generated electricity using resistors.

Hybrid makers just don't really care about that.

arnonejoe 2 days ago | parent | prev [-]

I test drove an EV and the regenerative braking was difficult to get used to. You have to constantly ride the gas pedal. I would buy an EV if it weren't for this feature.

schmookeeg 2 days ago | parent | next [-]

We have owned 4 EVs and each allow you to configure the regen braking strength. You'll need another reason to not buy one.

apelapan 2 days ago | parent [-]

Tesla is a quite common EV brand. They do not allow configuring regen braking, except for the behaviour at stand-still.

(They also don't do blending between friction brakes and regen, so the cars behaviour when letting of the accelerator is highly inconsistent depending on temperature and charge level).

One of the reasons I long for the lease on my Model Y to end so I can replace it with a less stupid vehicle.

stavros 2 days ago | parent | next [-]

I agree with the general sentiment, but this isn't relevant in the context of making a purchasing decision. Simply buy another brand.

apelapan 2 days ago | parent [-]

I have learned my lesson on regen. Lots of people online (and offline, for that matter) told me that you'll get used to the Tesla behaviour in no time and not to worry about it feeling weird during the test drive.

Many thousands kilometers later I hate it almost as much as at the start, so lack of regen configuration will be a dealbreaker next time I pick a new car.

stavros 2 days ago | parent [-]

Hmm, what do you hate about it? I have a BYD and I always leave it at "strong", as otherwise it's too little braking (same as an ICE).

apelapan 2 days ago | parent [-]

There are two aspect I don't like:

1. It is inconsistent, especially during winter and when fully charged.

2. Crossings with shrubbery/objects that hides approaching pedestrians/cars/bikes and it is rare that there is anyone actually crossing. I encounter these several times per day.

My preferred way of approaching #2 is to reduce speed well ahead, start gliding and put my foot on the break pedal to be ready for a complete halt in the rare case (once in a 500 maybe) that I need to give way to someone. In the Tesla I must reduce speed to almost standstill and creep slooooowly, since it would take half a second to move the right foot to the break.

I understand it sounds like an extreme corner case, but for me it is all the time every day. Central Scandinavia.

stavros 2 days ago | parent [-]

Hmm, I don't really understand what you mean. If I want to reduce speed far ahead, I just ease up on the throttle pedal a little, and the car slows down a little. If I ease up a lot, it slows down a lot. I'm not sure what you mean...

apelapan 2 days ago | parent | next [-]

I want to glide at roughly constant speed for some distance. Some mild breaking is fine. I cant glide if I let off the accelerator, then I come to a fairly firm stop.

I want my right foot on the break pedal, ready to brake hard and fast in the rare case that something comes across the road.

I don't want to reduce speed any further than is necessary to have a safe breaking distance at fully ready state.

With any other car (that I have driven) than the Tesla, I can approach a situation like this at between 20kmh and 40kmh, depending on the specifics. In the Tesla I need to go at between 5 and 10kmh.

stavros 2 days ago | parent [-]

Ah OK, I see what you mean. Yeah, on my car, that's a setting I can toggle.

eldaisfish 2 days ago | parent | prev [-]

regenerative braking can be uncomfortable for passengers as the car is constantly alternating between accelerating (or constant speed) and braking. It isn't even light braking, it is significant braking.

I generally turn off the auto regen braking because i find it uncomfortable.

Importantly, regenerative braking is a danger on icy roads. I disable it entirely in the winter in eastern Canada because it often causes the tires to lose grip.

stavros 2 days ago | parent | next [-]

I agree about the icy roads, but for the braking, that's easily remedied by just not completely releasing the accelerator. I just modulate how much I want to brake with the accelerator pedal.

apelapan 2 days ago | parent | prev [-]

There must be some connection between traction control and regen braking in newer Teslas, because I didn't really have any problems with it during the past winter. A friend working in auto industry was involved with doing competitor analysis and was shocked back in 2014 or something like that, the Teslas they tested simply spun out of control when letting go of the accelerator in slippery conditions.

They didn't care much for convential wisdom and car building competence in the early days of Tesla.

jjfoooo4 2 days ago | parent | prev [-]

Is that not what "Chill Mode" is? I've activated that on my car to relieve some of the jerkiness and it seems to have worked well

cloverich 2 days ago | parent | prev | next [-]

To be constructive, took me a little over a week to get used to. Also i test drove four, and absolutely hated 2 of them. One felt very similar to my ICE car (VW ID4). Eventually settled on ioniq and after a week, it quickly became my favorite driving car ever (which coming from sporty manual transmissions, is not at all what i expected or why i bought it).

All to say, check out a few to be sure, im still shocked how much i love driving this thing (and how criminally fast it is, totally absurd).

bruce511 2 days ago | parent | prev | next [-]

I don't think this comment should be down-voted since it is indeed a real point of difference and it is worth discussing.

The key takeaway is that there are differences to driving an EV to driving an ICE vehicle. Equally those differences are in fact easy to adjust to given a bit of practice.

Of course cars have always had different control options. Automatic and Manual gearboxes spring to mind. When I first learned some cars had a gear selector as an arm on the steering column, and so on.

EVs like a somewhat gentler foot, because the torque is instant, so a heavy foot is likely to be a more uncomfortable ride.

So yes, different cars, different styles. But of course we adjust very quickly, and its not really difficult to drive anything- it just takes a bit of practice.

Dylan16807 2 days ago | parent | next [-]

Except it's not a real point of difference. Just because some cars are programmed to act that way doesn't mean we should treat it like a universal constant of EVs. EVs can be programmed to only engage regenerative braking when the brake pedal is pressed, no riding the gas pedal needed.

dontlaugh 2 days ago | parent | prev [-]

Many electric cars are also overpowered. For those with a more reasonable ~100kw, gentleness hardly matters.

avidiax 2 days ago | parent | prev | next [-]

> you have to constantly ride the gas pedal.

Are you not? Do you drive by blipping the gas every few seconds?

I've had Uber drivers do this and it is annoying bordering on nauseating as a passenger. It is probably pretty bad for mileage and transmission wear as well (constantly taking up and releasing the backlash in the gears).

throwawaysoxjje 2 days ago | parent | prev | next [-]

I’ve got regenerative breaking on my EV without one pedal driving, it acts just like my other car does.

Rover222 2 days ago | parent | prev | next [-]

You can toggle off regen braking on most EVs

2 days ago | parent | prev | next [-]
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rgmerk 2 days ago | parent | prev | next [-]

Firstly, most EVs that have strong regenerative braking ("one-pedal") setups allow you to adjust the strength or turn it off. Tesla, as usual, is the outlier in this respect.

Secondly, I rented an EV for a week and by the end of it actually preferred the strong regen setting. It was convenient in stop-start traffic, and on a twisty road, you could use it to tighten the nose as you entered the corner.

NewJazz 2 days ago | parent [-]

As another data point, I've owned PHEVs and EVs for gosh 6 years now and I still prefer the "weak" regen with the Chevy paddle brake to modulate. Sometimes when I have a clear path, e.g. a down hill on a highway, I just throw it in neutral for a pure coast and shift back into drive when I need to.

mrpippy 2 days ago | parent | prev | next [-]

Some EVs allow different levels of regenerative braking to be selected. The Hyundai/Kia E-GMP-based cars have level 0-3 plus a 1-pedal mode, and also an "auto" mode that slows down more based on radar proximity to the car ahead.

KingMob 2 days ago | parent | prev | next [-]

> test drove

> was difficult to get used to

To ask the obvious, how used to something are you going to get on a test drive? It takes time.

tzs 2 days ago | parent | prev [-]

Take a look at more EVs. There are many that aren't as opinionated about how you should drive as the one you drove (a Tesla, by any chance?).

For example here is how it works in Hyundai EVs (and I'd guess Kia too). It is easy to set them so that they drive very similar to an ICE. I believe several others also work similarly. There are only a few that try to really push you to one pedal driving.

1. When use explicitly use the brake pedal that car uses regenerative braking unless you are trying to stop faster than regeneration can handle in which case it will also use the friction brakes.

There may be a setting somewhere in the settings menus where you can adjust how strong the braking is, but I don't remember because the way the car comes from the factory the brake peddle feels a lot like an ICE car's brake peddle.

2. There is a regeneration level setting that controls what happens when you ease up on the accelerator or remove your foot from it. This setting has 6 possible settings: Level 0, 1, 2, 3, i-Pedal, and Auto.

There are two paddles on the steering wheel that let you move through these settings quickly and easily, and you can do this while driving so you are free to pick whatever setting fits the conditions and your mood the best. Here's what they do.

• In level 0 there is no braking associated with the accelerator. Take your foot off and the car coasts is if it was in neutral.

• Level 1 provides a small amount of automatic braking when you let up on the accelerator. In ICE terms it is similar to the engine braking you would get on level ground going fast enough to be in 3rd gear in a 3 speed automatic. You slow down faster than coasting, but not so fast that if you were on the freeway and your felt the need to shake your right leg around a little it would slow enough to be a problem.

• Levels 2 and 3 step up the amount of automatic braking. 3 is enough that in city driving most of the time you can be quite leisurely when it comes to moving your foot from the accelerator to the brake at most stop signs, but it will not bring your car to a complete stop. It will get quite slow and then creep at that speed.

• i-Pedal is one pedal driving mode and corresponds to what that EV you test drove was doing. In this the braking is similar to level 3 as far as aggressiveness goes, but it will take you all the way to a stop most of the time. Once you get used to it you should be able to do most city driving and most highway driving without touching the brake pedal. About the only times you would need the brake pedal (outside of emergencies) is if a light changes on you when you are too close to the intersection.

• Auto mode automatically switches between 0, 1, 2, and 3 based on the distance to the vehicle in front (using the same system that adaptive cruise control uses) and the slope of the road. If you are on the freeway for example with a good distance between cars it will be in 0 or 1. In the city where you are close to the next car it might be in 2 or 3.

• If you press and hold the "increase regen level" paddle for at least 0.5 seconds it will switch from whatever your current setting is to i-Pedal and stay in i-Pedal as long as you continue to hold the paddle. Release the paddle and it switches back to whatever your previous setting was.

This system gives you plenty of flexibility and you should be able to easily find a setting you like. Some people really like one pedal driving and so they can just put it in i-Pedal and leave it there (with a slight annoyance...when you turn the car off in i-Pedal it comes back on in level 3, so you will have to hit the regen up paddle once).

Some people set it to one of the numbered levels and leave it there (again with slight annoyance at startup where it comes on at 1 so they need a paddle flick or two).

Some people use the paddles instead of the brake pedal, mixing levels to get the kind of deceleration curve they want.

I normally drive in level 0, with an occasional day or two in i-Pedal just for a change of pace, but if I'm coming up on a series of roundabouts I might switch it to i-Pedal. That's great for say a 35 mph road with 10-15 mph roundabouts every couple of blocks. (If it is just one roundabout I'd probably use the "hold regen up paddle for 0.5 seconds" option to just turn on i-Pedal for that intersection.