Hybrid cars can use FOUR TIMES more fuel than makers claim

The UK highway test is significantly different than US EPA and is not correlated to real world FE variables with a correction factor like the EPA test is. It’s basically what the US EPA test was up until the early 90’s.


This was not the UK highway test, so not sure what Which? test has to do with the regulations. They show % lower than advertised. Does BMW advertise different mileage in the UK and the US?

On average, hybrid cars were found to be 61 per cent less fuel-efficient than promised.

Which? said that their tests were tougher than the official ones, because they better represented real-world driving conditions.

I’m pretty sure they do as in US they will advertise EPA test figures and in UK it would be european test cycle (don’t remember what’s the acronym for it is). EPA and European tests are different, so the results would be different.

Even gallons are different

I’ve never heard of ‘which’ before.
What a dumb name for a Consumer watchdog group. Using such a generic name will mean you get lost in searches.

Lets see, real driving in our City miles don’t match up to driving on a test track with preset cones for stop / go. Well duh. Also are their drivers pros at saving gas or just something off the street? They need a baseline for all cars that can be done and repeated precisely.

The emissions mention at the bottom, intrigues me. Is start /stop going to pollute more than running the engine for 60 seconds? Why do hybrids issue double the emissions?

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Yeah, I guess so

Yes, BMW does “advertise” different fuel efficiency in the UK and US. The testing standards are completely different. Also the fuel economy rating is NOT SET BY THE OEM. It is set by the US EPA, and in the UK by the WLTP test. I am not sure which test that the article is referencing…that website looks like the National Enquirer and I have no interest in reading it in detail.

BMW 3 SERIES 330i Sport 4dr

Fuel Consumption - ICE

EC Combined (mpg): 47.9
EC Extra Urban (mpg): 56.5
EC Urban (mpg): 38.2
WLTP - FC (l/100km) - Comb: 6.6
WLTP - FC (l/100km) - Comb - Max: 6.9
WLTP - FC (l/100km) - Comb - Min: 6.5
WLTP - FC (l/100km) - Extra High: 6.4
WLTP - FC (l/100km) - High: 5.6
WLTP - FC (l/100km) - Low: 9.5
WLTP - FC (l/100km) - Medium: 6.6
WLTP - MPG - Comb: 43.5
WLTP - MPG - Comb - Max: 40.9
WLTP - MPG - Comb - Min: 43.5
WLTP - MPG - Extra High: 45.6
WLTP - MPG - High: 51.4
WLTP - MPG - Low: 30.4
WLTP - MPG - Medium: 43.5



1 US MPG = 1.201 UK MPG while 1 UK MPG is 0.8327 US MPG

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As a engineer, I prefer my metrics in km/L or L/100Km

Yes, yes. No idea what I was thinking. Probably not thinking lol

Man the WLTP is crazy for PHEV cars. I was not familiar with WLTP, only the old NEDC from college.


I’ve always really liked MPGe, it’s very easy to understand and allows electric or PHEV vehicles to be directly compared on the exact same footing in terms of energy efficiency.


I’ve been reading for 20 mins, I’m a mechanical engineer with a concentration in automotive powertrain and I still can’t understand how the EU/WLTP calculates these numbers for PHEV’s. It appears to be very shady.

I am guessing that what this magazine did is basically calculate the MPGe, but they don’t mention the math anywhere so who knows. But looks like the WLTP is broken for PHEV’s just like the NEDC was for all vehicles.


No worse than how the epa calculates mileage range for evs.

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Isn’t it based on energy density? Makes sense to me. Although it’s a relatively useless number for an EV.

No. They have a bunch of tests that can be done or you can do the standard tests and they slap a randomly selected 20% knock down factor that they never actually established a basis for. I’ll give you one guess which brand makes sure to do all the tests so they don’t get hit with a knock down, resulting in real world mileage that’s generally a good bit less than the rating and which brands get hit with the knockdown and then generating real world mileage that beats their epa numbers.

It’s almost like if you tune the vehicle specifically for the epa tests, you can get numbers that aren’t really real, but make you stand way out in the range game.

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I’m not surprised these slipped through the cracks and/or are inaccurately reported lol.

What was the running joke about the Uk highway test by Jeremy Clarkson? Been a while…or maybe he was making fun of EPA I forget.

Speaking of Clarkson, this topic was covered by Top Gear 12 years ago. They put a Prius and a BMW M3 on a racetrack and measured which one got better MPG. Spoiler alert: it was the M3.

Hybrids get a lot of their efficiency benefit from stop & go conditions. Most driving isn’t 100% highway or 100% city, so most hybrid owners get MPG numbers that they’re happy with.

Most people, especially on Toyota and Hyundai hybrids, are going to get pretty close to the EPA numbers in real life. Top Gear’s racetrack example illustrates why you’ll always want to drive the right car for the job. If your commute is 300 miles of highway at 90mph, maybe you want a Diesel VW or Cayenne or something instead of the Prius.


Well it’s settled then. I’m buying an M3 over a prius :+1: :+1:.


This is satire.



You should. My M4 is saving the planet :earth_americas:

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If I did buy anything it would be a M2CS.



We got rid of our Prius to make room for my 750i, and never looked back.