Are Hybrid mpg and co2 levels fantasy and misleading

smillion

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Is it just me ?

I'm fed up reading about stella mpg and minuscule co2 emissions on hybrid exec cars, which attract all the relevant benefits of low emission vehicles including full tax allowances for businesses that buy them and low benefit in kind for employees that run them. And yet "real world" emissions and mpg seem to be so different. Or have a got it wrong.

The latest is on the front page of Auto Express that shows the BMW 530e with 141mog .... and yet the article shows real world mpg of 37 mpg and an electric range of 20 compared to suggested 31.

Who's kidding who here? And to top it all the government are happy to provide huge incentives to achieve these fantasy figures.

Or am I missing something.

To think we were concerned about the misstated VW key numbers ..... the hybrid take the truth and real world to another level......

I'm all for chasing new technology. But I'm not happy with the potential for misrepresentation.

Tell me otherwise

Marc
 

geraldrobins

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I dont think its misrepresentation its the nature of the official tests that doesn't represent real world driving. Wasnt the VW thing more about nox emissions than mpg.
 

MarkACLS

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You're not missing something. They only need to do the MPG and emissions over a couple of KMs.

Outside of that it's real world. Hybrid = great for milking the system of lower tax brackets but not so good for real driving economy.

Looks pretty interesting for performance augmentation though.

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smillion

smillion

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I dont think its misrepresentation its the nature of the official tests that doesn't represent real world driving. Wasnt the VW thing more about nox emissions than mpg.

One of my clients has a BMW i8 , attracted by the tax breaks and huge mpg. In his real world the car gets around 30mog and far from the published figures "possible". He feels as if he's been misrepresented. Although that said he has no regrets as the tax breaks are still attractive for the self employed. ......
 

wivenhoe

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I dont think its misrepresentation its the nature of the official tests that doesn't represent real world driving. Wasnt the VW thing more about nox emissions than mpg.

I enjoyed driving my 2014 CLS 350CDI and achieved an average of 40mpg. I saw they way things were going with diesels and bought a C350e. I was never taken in by the alleged 138mpg but I did think that the fact it could travel circa 20 miles on electric would pay dividends in term of future congestion charging and emissions. I did 20 miles around town today and achieved 75mpg but more importantly the amount of emissions was negligible as the engine was hardly used. As the problem seems to be in towns rather than main roads surely plug in hybrids must be at least part of the answer to reducing damaging emissions.

No doubt there will be views that the charging electricity produces emissions but they are not of the health damaging nox emissions. My C350e is faster than the CLS350CDI so I have not had to sacrifice performance and whilst the emissions of 48 may be understated it will be nowhere near the 350CDI in the real world.
 

Chris-S

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Went to the shops in our C350e today and got 100.9 mpg, the missus usually sees in excess of 200mpg for that trip. Did a 50 mile trip the other day and got just under 60mpg.

The results are totally dependant on the length and nature of the trip, but the car can achieve the official figures with ease...on the right type of journey.

No denying they are a total tax dodge, but if you happen to do lots of short trips, you won't be complaining. I wouldn't have picked one if I was a motorway warrior though.

Quite agree about the performance enhancing feature though. Hard to argue with 600Nm from a 2l that often reports over 200mpg on our shortest trips. (Note for the pedants, the in car reading maxes out at 99.9mpg, have to use the app to see actual figures over that value).

Whether it is a smart choice in terms of reliability...time will tell. Clearly it is rather more complex than either a pure EV or ICE, and is arguably the worst of both worlds, but EVs are doing big miles with no worries and it would be nice to think that MB can build an ICE car to do a few miles without trouble. I know I wasn't at all convinced anout the idea a few years back, but now, it works well for me. I'd still prefer a pure EV but just couldn't bring myself to spend £75k on a Tesla.

There's also some validity to the argument that a lot of official MPG figures are just unattainable ******** in the real world. Be interesting to see how the hybrids do when the testing regimes change to better reflect reality.
 

Londonscottish

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it would be nice to think that MB can build an ICE car to do a few miles without trouble. I know I wasn't at all convinced about the idea a few years back, but now, it works well for me. I'd still prefer a pure EV but just couldn't bring myself to spend £75k on a Tesla.

For town, anyway, the i3-type idea of having what's effectively an EV with a back up petrol generator makes a lot of sense to me. It's basically an EV with a range extender.

For motorways maybe the best solution would be have one the other way round - eg small capacity petrol with twin turbos to give you torque and batteries to give you a KERS-like boost. On long trips you've still got 300 bhp-ish and 30+ MPG. Round town you can drive 20 odd miles silently and efficiently on the batteries. I'll have mine with a 2.5 V6 please.
 
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Chris-S

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For town, anyway, the i3-type idea of having what's effectively an EV with a back up petrol generator makes a lot of sense to me. It's basically an EV with a range extender.

For motorways maybe the best solution would be have one the other way round - eg small capacity petrol with twin turbos to give you torque and batteries to give you a KERS-like boost. On long trips you've still got 300 bhp-ish and 30+ MPG. Round town you can drive 20 odd miles silently and efficiently on the batteries. I'll have mine with a 2.5 V6 please.

The 350e almost gives you that already. Combined output is about 285bhp & 600Nm with boost and based on numbers from folk who have done a lot more miles than me, average mpg figures in the high 50s are common. Battery only range is a bit dissapointing though, I've only seen about 14 miles so far myself, but that should improve as the ambient temperatures rise a bit.

I'd like a V6 too, the 4 pot sounds absolutely dire......
 

CabrioDave

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Fantasy? No.
Misleading? Depends on whether you are comparing like with like.

The two tests which are used to establish the "official" figures have very specific patterns of acceleration, speed, timing, etc. The urban one covers 2.5 miles, at an average of 12 mph (max 31). The extra-urban one starts with a warm engine, and covers just 4.3 miles, at an average of 39 mph (max 75).

These are conditions which suit electric/hybrid vehicles brilliantly, so they'll produce very high figures.

The tests do NOT involve extended distances at main road or motorway speeds (where those same vehicles will not do so well).

Many people confuse the "extra urban" testing cycle with "long run" expectations.
 

Londonscottish

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The 350e almost gives you that already. Combined output is about 285bhp & 600Nm with boost and based on numbers from folk who have done a lot more miles than me, average mpg figures in the high 50s are common. Battery only range is a bit dissapointing though, I've only seen about 14 miles so far myself, but that should improve as the ambient temperatures rise a bit.

I'd like a V6 too, the 4 pot sounds absolutely dire......

Is yours petrol or diesel?
 

Londonscottish

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The 350e is always petrol, isn't it?

I don't know. I think the original E300e's were diesel and then they switched to petrol.

I'd hoped that the petrol engine would have been smooth. And it surely must be compared to the 2.1 diesel.

(I'm just wondering as I may well end up in one in a few years' time).
 

Tuercas viejas

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I feel i should comment.
Hybrids and electric cars have one thing their ICE cousins don't have, The power to launch.

Remember an electric motor produces its max power (torque) at zero revolutions.
Hence its distinct advantages are in city stop and go traffic.

Certainly with a smaller engine and Hybrid drive the combination gives much more power and reduced fuel consumption on city and urban operations than bigger displacement pure ICE alternatives .
I have much more experience when comparing the Lexus 300H hybrid against its full blown ICE stablemate. The 300H wins hands down and only on long runs do the numbers start get closer. .

I am curious why MB did introduce a diesel hybrid.
I once ran into gaggle of Toyota diesel hybrid Highlanders on a factory test in the Colorado mountains years ago. I was doing a similar double decker durability test for Leyland Bus. The factory engineer and myself talked turkey briefly about how they were going to get enough constant heat into the SOC cat to achieve re-gen & auto clean activity. It wasn't positive that's for sure but that was quite a few years go now.
Tuercas Viejas
 

Chris-S

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C300h is diesel non plug in hybrid, C & E350e are petrol PHEV.

No surprise the hybrids do well on those test parameters.
 

grober

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Its possible that the E300 was in reality an intermediary step/test bed between stop start and a full plug in hybrid. I believe the inline electric motor functioned as a starter motor in addition to its limited other function as a propulsion unit which might re-enforce this perception . The choice of diesel for ICE fuel does seem strange bearing in mind your remarks about SOC cat regeneration but perhaps reflected European manufacturer's faith in the diesel engine at the time before the NOx issue hit the fan. I am left with the impression that the E300 was an ICE vehicle with an electrical assist/ range extender facility rather than a committed attemp at a full fat hybrid with propulsion more equally shared between Electrical energy and an ICE. As such it functioned well under certain driving conditions but was perhaps deficient in the now crucial area of predominantly cold start urban motoring.
A model to be avoided second hand perhaps unless someone's motoring use really fits its restricted abilities in the light of recent emission regs . :dk:

Mercedes do appear to be continuing with their "hybrid light" vehicles theme however with their 48volt electric assist range of new engines. These to be separate from the high voltage full hybrid systems found in their plug in hybrids. the function again seems to centre round range extension.
https://www.autocar.co.uk/car-news/new-cars/facelifted-mercedes-s-class-get-new-48v-mild-hybrid-tech

mercedes-news-2-079.jpg
 
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CROSS1880

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I have recently bought a c350e and can say my fuel bills have more than halved and about 58-70 mpg would be the norm if you do continuous motorway journeys 45 mpg is the norm at average 75-80 mph which I can live with still better than my old diesel it replaced and given it has near 300 horse on tap it's far more exciting than a diesel as well and £0 road tax whats not to like


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whitenemesis

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Mercedes are playing catch-up in regards hybrid technologies. Toyota/Lexus are generations ahead.

Plus the Lexus e-CVT transmission is a real gem. Small and mechanically so simple.
 

Tuercas viejas

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Mercedes are playing catch-up in regards hybrid technologies. Toyota/Lexus are generations ahead.

Plus the Lexus e-CVT transmission is a real gem. Small and mechanically so simple.

Yes it is.
Really a marvel, being basically simple but devilish complicated to actually work in service reliably.
Having just ONE single eppicyclic pack the secret is the fact that the smaller of the electric motors MG 2 can actually turn the planet carrier to produce a CVT transmission with infinite reductions to suit the input of the ICE and the output of the main traction motor MG1 .
Both inputs/outputs are read by producing a Sine and Cosine wave speed sensor signals which is then computed through what is known as the resolver circuitry to get the right meld of engine and electrical traction motor inputs /output synchronization and battery regeneration (regenerative braking) on the over-run.
Whether or not you are attracted to Hybrids this Toyota Ainsin invention has to be very impressive from an MV engineering viewpoint.
Tuercas Viejas
 

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