MHEV like Audi or MB do not help in overtaking or in the city. It's only for coasting, there is a small electric motor that will only help to re-start the engine. It's basically a better start-stop for driving on highways - you don't notice that the car is in "neutral" gear with the motor turned off. It helps a bit, but I would definitely not call this a hybrid, not even a mild hybrid. But - I saved 50% of the registration tax, so I don't complain.

> It's only for coasting, there is a small electric motor that will only help to re-start the engine [but not really pull the vehicle].

Classifying a car as a mild hybrid electric vehicle on the basis of nothing but a glorified starter motor doesn't sound entirely unlike something Volkswagen Group might try to get away with, but this doesn't seem like a fair assessment. Doesn't conventional coasting mean that the ICE still is driving the wheels — at idle RPM? So if instead the clutch decouples, the electric motor has to make up the difference, right? That's not nothing when you consider that diesels (such as your Audi) output significantly more power at idle RPM (and also use more fuel, I'd guess?) than petrol engines (relative to max power).

The engine decouples and either shuts down completely (if you don't have Start-Stop switched off) or it just idles on low RPM. Before the Audi I had a BMW that wasn't classified as MHEV and it still would decouple the engine during coasting (in Eco mode), but it would not turn it off because this would add a delay of 1-2 seconds until the engine is ready again (and it didn't have the additional battery + electric motor to start it in these conditions). The small electric motor helps to quickly start the motor in this decoupled mode (which again is not something that only hybrids have) and so it can be turned off for up to 40 seconds of coasting. All of this can be disabled in the Settings menu and the engine will never go into "coasting" mode and this coasting mode will almost never be triggered in the city anyway (you can see that it will shift from a specific gear like 6 to just "D" - and then you know that the engine is decoupled). Anyway, I and many others (most?) turn off the start-stop right when you start the vehicle. I just don't like that the engine turns off on every intersection and then you have a second of delay and slow response + more wear on engine for so many starts and stops. In this case it will still coast with the decoupled - but idling - engine.

Also by coasting I mean condition where the car has enough momentum and either goes downhill or there is a slower speed limit ahead (this is detected automatically from map data) and the car knows that it can just decouple the engine. This is evaluated by the car based on some conditions, it's not controlled by the driver.

Thank you! I just quickly looked up some terminology and it turns out the mode I'd been thinking of is more properly called ‘coasting in gear’, which is indeed not at all implied by the more general term ‘coasting‘. Now that I know what's what, I agree that Audi's quarter-assed implementation shouldn't qualify as ‘MHEV‘.

More information directly from Audi: https://www.audi-mediacenter.com/en/techday-on-combustion-en...

"The 48-volt-based MHEV technology is particularly more comfortable and efficient. If the driver takes his foot off the accelerator at a speed between 55 and 160 km/h (34.2 to 99.4 mph), the car can coast for up to 40 seconds with the engine off completely. During slow coasting, the start-stop phase already begins at 22 km/h (13.7 mph).

Once the driver accelerates again – whether from a stop or while driving – the vehicle restarts quickly and very comfortably: the BAS revs up the internal combustion engine to the target speed, then injection occurs again and, in the case of a gasoline engine, ignition. While the conventional pinion starter remains on board, it practically comes into play only at the initial starting, if the engine oil is still cold and viscous. In such a situation, the belt of the BAS could slip through. "

Btw, expect huge taxes to hit electric cars in Europe. The European governments have a significant part of their budget coming from gas tax and they are not happy with that revenue stream going away. For those not from Europe: It is pretty common for us to have to pay $4-5 tax per gallon of fuel.

The UK government is doing the complete opposite in fact. They’ll give you a grant towards the cost of a new EV, a grant for a wall box to be installed at you home, 0% tax on company car benefits if it’s an EV, 0% road tax, etc. They’ve even just moved The ban on new petrol and diesel sales forward to 2030.

Fuel duties help to offset the negative externalities to society of driving, namely CO2 emissions, pollution and congestion. With EVs tou don’t have emissions and pollutions and the health problems they bring so there’s no negatives to offset (ie fuel duty revenue will go down, but so will spending on health and environmental related issues)

There’s still the congestion any vehicle can cause and I think we’ll move to a much different form of vehicle taxation over the next 20 years, perhaps with more toll roads or even surge pricing style taxation for usage of roads.

> The UK government is doing the complete opposite in fact. They’ll give you a grant towards the cost of a new EV, a grant for a wall box to be installed at you home, 0% tax on company car benefits if it’s an EV, 0% road tax, etc.

Taxing will have to change and evolve either way.

Today it makes sense to incentivize the move to EVs. But this says nothing about what will happen when everyone is there and people no longer have the option of buying or using an ICE. Some years from now taxing EVs with some form of "road tax" (today included in the price of fuel) will be the low hanging fruit and the technological means may already be there. Your car will likely be able or even required to log and report the distance driven for taxing purposes.

If truly autonomous vehicles do catch on and incentivize moving away from private ownership, it will also have a huge impact on the way cars are taxed or how the taxes are passed on to the user.

The easiest way to replace petrol tax would be to simply charge with the MOT. Road taxes in general raise about 10p per mile driven (including petrol, VAT on petrol, and VED, but excluding VAT on new cars, which is a significant amount - about £10b a year based on 3 million cars a year at £20k a year)

It would work as "You've done 10,000 miles since your last MOT, you have to pay your £1k tax bill". Travel abroad and you could register the mileage when you leave and when you get back easily enough. Final bill on scrapping or on SORN.

That wouldn't allow the differential road pricing that tracking fans want, and wouldn't work in Ireland, but would work in GB right now.

Of course you have! Emissions from tires and brake pads are very significant. CO2 and pollution from driving is just externalized - where do you think all that electricity for charging EVs is coming from? Also, pollution from manufacturing EVs is still there.

Emissions from brake pads on EVs are almost non existent (regen braking). This is a vast departure from combustion powered vehicles where PM from braking systems, from exhaust catalytic converters etc. etc. contribute a lot of the grime you see at the edge of a motorway. EVs do make this better.

Tire emissions are NOT a factor we need to be concerned with however :-) Tire manufacture, sure. From waste - most definitely. But emissions from driving are not something to worry about even with the billions of miles driven annually on tires.

Last time I looked at PM2.5 I found the source below[1]. Which lists PM2.5 from tire wear at 0.001 gm per miles. Which is less than brake wear at 0.003. Notable that as you said EV's have much less brake wear.

https://www.bts.gov/content/estimated-national-average-vehic...

[1] Was a lot harder to find it again because someones running an SEO agitprop campaign to blame PM2.5 on tires instead of diesel exhaust. I had wade through GIS pages of trash websites to find it again.

Yeah that looks about right. Brake pad PM2.5 is 3x that of tires but both pale into insignificance next to exhaust PM2.5 at almost 10x that of brake pad and tire emissions added together.

The nice thing about EVs is those exhaust emissions are moved away from the tailpipe in populated areas to power generation facilities.

The efficiency of electric vehicles is almost 3x that of the gasoline cycle of drilling, transporting, distilling, transporting again, combusting then achieving almost 30% motion from the chemical energy of gas.

So because of this efficiency there’s just less emissions overall even though the emissions are away from population centres.

Then lastly, the emissions are consolidated in one place so capture and cleaning becomes viable.

EVs are not perfect but they are so much better than gasoline powered vehicles that if you can at all accomodate the switch, then it would be great to consider it.

The sun and wind? If everyone went to smart charging infrastructure your vehicle could easily stay topped up during excess generation.

> If everyone went to smart charging infrastructure your vehicle could easily stay topped up during excess generation

...and yet from today's headlines:

British coal plants fired up to meet temporary electricity shortfall. Remaining UK coal plants, including Drax, supply 6% of grid’s electricity to cover power supply drop and colder weather

https://www.theguardian.com/business/2020/nov/26/british-coa...

Also note:

"renewable electricity was in relatively short supply in western Europe too, meaning the UK would need to keep running its coal plants while exporting power to France and to the Netherlands via cable interconnectors"

Don't forget the UK is FAR ahead of the US when it comes to renewables, which of course is easier when you have a single national grid (and can buy spare French nuclear when you have a dip in capacity)

Emission from brake pads is way less than ICE cars due to regenerative braking of the EV motors; one pedal driving is awesome.

This is a good article which answers most of your doubts:

https://www.motorbiscuit.com/are-electric-cars-worse-for-the...

Spoiler alert: EV pollutes less than ICE

I am aware that EVs pollute less. But parent comment claimed that pollution doesn't exist at all which is simply false.

Fair enough, it exists in some regard... let's change that to pollution caused by the powerplant of the vehicle.

I'm not wholly informed here, but just by using common sense, I can only imagine we're talking fractions of a percent for brake pad and tyre pollution, so I wouldn't pick that hill to die on personally.

Correct, the potential CO2 emissions are externalised but the electricity can come from wind, sun, nuclear, or even fossil fuel power stations that run more efficiently and cleanly than an ICE.

Also, I'll take the emissions from tires and brake pads over those from an engine for sure.

Even if the energy source would still be purely fossile-based (which it isn't), it would still be a net win, since large power plants are more efficient than ICE vehicles and are better set up to reduce emissions other than CO2.

Yeah you can put good filters and carbon sequestration tech onto those plants much easier than putting it onto all cars.

1). Every year the percentage of renewable electricity is increasing on the grids worldwide so over time electric cars will pollute less. 2). Looking at the parts of an electric car vehicle compared to petrol/diesel cars electric car production has less pollution. 3) Electric cars have regenerative braking so even the brake pads pollution is less in electric cars

>> With EVs tou don’t have emissions and pollutions

You don't have them at the tailpipe, which I guess is really the key thing because it means a reduction in asthma and deaths due to PM in habited areas.

You do still have emissions, they're just emitted away from where humans live. It's a great improvement but not a complete solution.

These replacement taxes need to come from road use charging, to deal with congestion during commutes.

Shifting non-essential travel to an hour earlier or later in the day will have a hugely beneficial impact in unclogging many cities.

How does one classify travel as essential or non-essential?

"Essential" means "all bosses have agreed on this arbitrary time to start work so all workers can enjoy congestion and stuffed subways".

We pay similar gas tax in the US, but we don't pay it at the pump. There are direct subsidies around $20 B/yr [1] and indirect ones, such as $2 T for a couple of gulf wars which were clearly about oil. Then there's spills, climate FUD from the oil companies [2] which will cost us for centuries in floods, fires, and other climate exacerbated disasters.

If anything we need to tax the hell out of fossil fuel to break even with its actual costs.

1. https://www.eesi.org/papers/view/fact-sheet-fossil-fuel-subs...

2. https://www.latimes.com/environment/story/2019-10-21/oil-com...

I wonder why people aren’t excited about hybrids, they seem like a genuine next step of automotive engineering to me. Petrolheads of all people hate it the most, and that feels wrong. If you think twin turbo is superior to single, then THS II should be vastly more so.

I personally blame it to Toyota’s horrible packaging. The thorough objective horrendousness of Prius is inexcusable, especially the latest ones. But that shouldn’t decide on the technology!

It adds a lot of weight for not a lot of benefit, on either side. A pure-electric drive gives amazing benefits in torque and latency reduction, but the motors on MHEVs and even PHEVs don't give enough "oomph" to justify the complexity, the cost, or the added weight.

The Koeingsegg One:1 is exciting. The BMW i3 is exciting. The Jaguar I-Pace is exciting. Heck, the Tesla is exciting. The BMW 3-series hybrid is $15,000 more for not a whole lot.

> exciting

(Full disclosure: two working parents, three young kids, not a lot of spare time and even less spare money...)

We own two (ICE) cars, a seven-seater that's diesel-powered and a four-seater that's petrol. Neither of them are even remotely "exciting" (both have the smallest, most economical engines that the manufacturer offers for that model). We would not be looking for "exciting" in a replacement for either of them, either.

What I am looking for is a like-for-like replacement that isn't hugely more expensive.

With electric, I'm struggling.

We [very briefly] sat in the battery version of the four-seater in the showroom when we bought the petrol, it cost more than twice as much, range was dire, and the sales guy pointed out that it wouldn't hold its purchase value as battery technology is changing so rapidly. So that was that :(

I would love to switch to electric, but right now we don't have the spare cash to throw around.

"Exciting" might be great for persuading petrolheads and/or the wealthy and/or the virtue-signallers to switch, but for everyone else, what can pure-electric offer?

Insightful!

I feel the same, I sold my car 8 years ago and never bought a new one since, I'm planning to get a new one (hopefully kids, old parents, I'm gonna need it sooner or later) but I am struggling too.

I usually use the Renault Zoe as an example, the EV model costs 40% more (~26,000 euros VS ~37,000 euros) for no - obvious - added benefit, it's the same exact car.

I've been researching and thanks to state bonuses I could buy a Renault Twingo EV for ~17,000 euros, it's a very good deal but it's a smaller car, not that it's a problem now, I still mainly drive inside the city, but it makes me think of the economy of the operation: I need it for a future larger family, I should settle down on a smaller car.

I'm probably getting it anyway and I am also excited about it, but really it shouldn't be about excitement, it should be about being a better deal overall.

Because it drives like crap compared to an all petrol vehicle, that's why. Toyotas feel like they're all made for grannies - you step on the acceleration and it's just sluggish. My mom test drived one and bought a Seat instead. Another guy told me he drove a company Toyota hybrid and he'll be getting a petrol BMW. There you have it.

It’s Toyota dragging down the technology by making horrible cars, clearly, themselves conscious or not.

Like, Fisker Karma was basically as fast and quick as a Tesla. Lots of hybrid hypercars are faster than petrol counterparts. It’s Toyota Prius that’s smearing hybrids.