All very well. Until you're stuck behind a diesel powered vehicle, especially in very cold temps. They STINK. I've noticed even the supposedly "cleaner" diesels still have that black soot residue near the tailpipe

The EU still allows diesel powered vehicles to emit a lot more NOx and PM-10 than a gasoline vehicle. If you force diesel powered vehicles to meet the same NOx and PM10 emissions as a California Emissions gasoline car, forget about it

Oh sure, there are gadgets to add on, like urea injection in the like. Once you start tacking all the emissions stuff onto a diesel, the fuel economy tends to plummet

When Dodge first put the Cummins in their 3/4 and 1 ton trucks, they had unbelievable fuel economy. Now with all the emissions stuff, not so good.

One of my co-workers used to have a 1993 Dodge 1 ton to pull a heavy camper. He felt it was a bit long in the tooth, despite running just fine, so last year sold it and got a new Dodge 3/4 ton diesel. He completely regrets that decision

Not to mention that if he indeed drove it two miles on battery power alone its gonna kill the consumption for a good while as it now has to completely recharge the depleted battery. Which this obviously reveals that the guy also has no idea on how to ideally drive the Prius. If they really want to make their test fair, have two people who are expert or experienced drivers for each vehicle. And something Europeans don't seem to realize is that Diesel is probably only available at 1/3 of all US gas stations.

The BMW did very well for its size. Its surprising how well euro diesels do compared to what is sold in the USA. A better review would be a 3 series with the same engine as its closer in price, size, weight etc to the Prius.

This shows how far cars have come as a car the size of the 5 series can do 55mpg without hybrid tech. Its one thing when a small light car does this with diesel, thats not too hard to do. Its another when a large car does it.

In the real world of course the Prius is using a good deal less actual energy as the diesel contains more power per gallon.

Why do we keep seeing these hybrid vs. diesel comparisons? Diesel has more energy per gallon, and diesel engines have much higher compression, both of which make for better mileage. Diesel here in the U.S is also 20-25% more expensive than gas, so at least here, they would need to get that much better mileage to be competitive. Besides, a diesel hybrid would even get better mileage. Compare gas cars to diesel cars, and hybrid gas cars to hybrid diesels cars.
Of course the clincher is they compared a manual transmission-equipped car to an automatic one. A Prius with a manual transmission would probably get much better mileage, but then noone here would buy it!

So I read this article and there's no direct comparison of mileage except way down in the fine print. Also, no comparison of the emissions numbers they're touting for the beamer. My bull shit alarm goes off, so after doing some math and assuming they're talking about imperial gallons (and people say Americans are insular) I get 50.05 mp(I)g compared to the fine print 50.5 mpg compared to the 48.3 mpg. 4% different! Wow, stop the presses. You'd think such a high tech site would put some error bars on their measurements. But worrying about the impact of the stereo on mileages kinda tips it off. These guys are full of it.

OK... So the Prius isn't the most efficient highway car in Europe. Is this really a surprise. Still the most efficient car in the US. Bring the Diesels over the pond and I'll be content driving the second most efficient car in the US.

Till then...

WERE NUMBER 1 !!!

In the fine print the actual fuel spend for each car was 45 pence more for the Prius than the BMW but the BMW had a premium on the price of 6.5k pound so how long will it take to recover the BMW premium at a rate of 45 pence per 500 mile trip?

Crap comparo when it was claimed "...to give the Prius the advantage of running in urban conditions where its petrol-electric drivetrain comes into its own." but 80% of the test was on motorways and B roads or country roads.

Why doesn't anyone do a comparo between 2 cars driving them from a common abode to a common work place each day for 5 days then a bit of a drive in the country for a couple of hours? That would be more like average use.

Clearly they got the wrong person to drive the Prius

Flooring the throttle to "break the boredom" is never good.

Anyway, I feel this "race" was a bit mismatched.
6 speed manual, 75mph speeds

UK£ 54.19 = 110.016538 U.S. dollars
UK£ 54.64 = 110.930128 U.S. dollars

At least the guy with the prius only spent 92 cents extra on fuel due to fuel price differences.

Another odd thing: I don't remember the Prius costing 41,978 USD!?
is google conversion converting these currencies wrong or something?

It is $37400AU and out tax is lower than the UK. Vehicles have high tax there. I'm guessing the BMW cops the same tax.

We took along a conventionally powered car – a diesel BMW executive saloon – for comparison and drove both cars an identical number of miles (545).

so not the same route???
don't think thats fare

Another feature designed to cut running costs is the brake regenerative system

this must be a concept car then never seen a bmw with reg braking!

They didn't say that, they were driving in tandem.

Unlike Toyota who aim to sell full hybrid technology in a very small percentage of their global vehicle sales, BMW have opted to cut the fuel consumption of their entire fleet by adding something they call "Efficient Dynamics" to every single model they produce.

The results at the fuel pumps are dramatic, but in essence it's all based on a number of relatively small changes.

The "regenerative braking" all new BMWs now have is not quite the proper regen you get on a full hybrid, but is actually a clever use of the alternator. It only saps power from the engine when you brake, or when the battery gets a bit low, otherwise that large parasitic loss is absent.

Other 'efficient dynamics' improvements are low rolling resistance tyres, low aerodynamic coefficients, automatic front grille closing, longer gear ratios etc.

There is a vocal minority of diesel fanboys that will take any opportunity to preach about diesels. Even on non-automotive forums that I frequent. Some of these people write for online or print automotive magazines.

Recurring themes include:

-fuzzy math (Imperial gals/US gals)

-apples to oranges comparisons (sub-compact 70 hp diesels that don't meet US emissions or safety standards vs. the Prius, European diesel vs. gas prices, etc.)

-diesel is a panacea (would solve global warming, oil dependence, obesity, etc.)

-EPA conspiracy against diesel.

I keep hearing about how great diesel is, how it's going to take over the US market, and how they can't wait for them to be re-introduced to the US market. I say, bring them on and let everyone see how great (or not) they are. Let's end the apples-to-oranges biased comparisons.

Of all people, GM's Lutz has been quoted as saying diesel isn't a panacea and that meeting emissions requirements in the US would result in a bigger diesel premium (initial purchase & maintenance down the road) as well as reducing fuel economy.

Once a Euro diesel has been modified to meet US emissions and safety requirements, its slight fuel economy advantage (on a MPG basis only, not adjusted for diesel's higher cost or energy content) will disappear. American consumers will want the things they're accustomed to such as automatic transmission, better acceleration and various electronic gizmos.

The Prius mentioned in the article is the T Spirit which is close in equipment content to Touring pkg 6 model. The US$ has devalued so much while manufacturers are reluctant to adjust pricing to account for the devaluation in order to maintain their relative market share. Hence vehicles are a true bargain in the US compared to the rest of the world.

I tried to post this comment there but I only got error messages:

The BMW 520d uses a different type of fuel than the Toyota Prius. May I suggest that you take the difference in the type of fuel into account?

The BMW 520d uses diesel.
The Toyota Prius uses petrol.
Diesel is about 17% heavier, contains about 11% more energy, and produces about 13% more CO2 per gallon than petrol.

If you take these differences into account, then the results of the test look like this:
In this test, the 520d used about 4% fewer gallons of fuel, but used about 13% more fuel by weight, about 6% more energy and produced about 8% more CO2 than the Prius.

Oh, you mean those knuckle-dragging rednecks who do weird mods to their 3/4 and 1 ton turbodiesel trucks, like CUT OFF the DPF and emissions stuff? Then claim all that black smoke gushing out is "harmless?" I say run a hose from the exhaust into their trailer home, after all the black smoke is "harmless"

The EU still allows diesel cars to pump out a lot more NOx and PM10 than a gasoline motor. We tend to tier emission class by weight, but in theory there is no longer any distinction between gasoline or diesel: both must meet the same emissions

The Diesel Car, An Environmental Black Sheep, On the Road to Reform

UCS Particulate Matter Testimony

Diesel Engines and Public Health

The Diesel Dilemma: Diesel's Role in the Race for Clean Cars

In particular, download the report from the last URL I provided and read the details.

In the US, the new federal regulations set a diesel NOx cap of 0.2 grams per mile for 2009. The EU allows 1.04, with "tough" standards set at 0.5, the EU car makers are struggling to meet

PM10 for diesels is set at 0.01 grams per mile, the EU currently is struggling to meet 0.11.

I find it very convenient that diesel proponents look at just one emission - CO2 - and ignore or downplay NOx and PM10

2 really nice postst
only here in the EU diesels do produce less co2 then similar petrol cars

This was a really interesting article and as a new Prius owner and also a previous BMW520 Auto petrol owner (traded in for the Prius) I can relate to it.

BMW have come on in leaps and bounds with fuel consumption and I can testify that less than 19 mpg is not great on the BMW I had. Ok so the trial was with a diesel manual, not a petrol automatic, but 50mpg compared to 19mpg is a good improvement.

Despite the headlining of the Prius as a Gas Guzzler, there wasn't much in it really was there? Also "fair" playing fields of a week of commuting may reveal a different result, but it shouldn't bother you that diesels are just as good in mpg because a Prius offers a whole lot more, which is why I put my money where my mouth is and bought one.

Well done that a big beemer got over 50mpg, about time too, but the thing for me is that I am more than happy if my Prius gets 50mpg because that's better use of a scarce resource than anything else I've ever had.

And you know the really nice thing about the Prius ? I took ownership of my Prius on Friday and drove it up to Manchester over the weekend to show it to my son and my brother... and my skeptic son now thinks its a really cool car and he wants a hybrid too. My brother thought it was fantastic engineering (he's a mechanic amongst other things) and might get one; and on my whole trip of over 350 miles I averaged 50.5 mpg first trip, mostly freeway.. and saw just 1, yes ONE other Prius on the whole journey there and back, while every other car seemed to be a BMW or Audi or VW.

I feel I have an exclusive car; it walks the talk at 50mpg which pleases me no end, its comfortable, and its green. Not many BM's are in that exclusive club, even the tested one isn't that green with NOx emissions, so yeah on the whole and on reflection, my Prius is a whole lot better than my old BM 520 and a whole lot better than this new clean diesel one too.