BMW 5 Series Beat Prius in MPGs?

The prius driver would have won if they found someone that knew how to drive it.

 

This is the most likely the test your are referring to: BMW 520d beats Prius in gas mileage - Autoblog

Readers of London's Sunday Times kept telling the auto reporters that the official mileage numbers for the Prius were overstated by about 15 imperial mpg. Intrigued, the Times decided to test things out by running a Prius against a BMW 520d with regenerative braking from London to Geneva, a 460-mile trip. Then they added 100 miles of urban running to give the Prius a chance to recover ground on its proper turf.

The verdict: the conventional diesel with Efficient Dynamics beat the full hybrid by 2.2 imperial mpg, or 1.8 US mpg. This means that an executive sedan with all the mod-cons and 500 extra pounds beat the mollusk-shaped sip-tastic wunderkind known as the Prius. And the diesel's CO2 emissions are just 32 g/km higher than the hybrid poster-child, to boot.

Admittedly, we find the test a bit unfair -- the Prius is not meant show its muscle at "75-mph into a headwind," and adding 100 miles of urban driving doesn't make up for 460 miles of autoroute. Reverse those driving conditions and then let's see who won. Still, for all of us diesel fans out there, it's a feather we won't mind putting in the cap.

Diesel cars can achieve some very good numbers. It's nothing too amazing if you live in Europe and have had access to these cars for decades. I've been very impressed with the cars that I've had as rentals in Europe. I've had a C-Class, E-Class Mercedes and lots of VW Passats. The worst mileage I got was ~ 32 mpg (US) BTW, both the C-Class and the Passats top out at 220 kph or 137 mph. I didn't get a chance to top out the E-Class because I had it in the Czech Republic.

 

Wouldn't matter much in the U.S. presently. Where I am diesel costs 67% more than gasoline.

 

whats next? land rover beats prius in off road test mpg?

 

As Shawn said...costs include the price of the fuel, price of the car, and resale if you ever wish to turn loose of your Prius. Owners of 5 series d BMWs have comfortable, speedy, expensive to buy, service, and own autos.

Give me my Prius with high mpg, moderate costs for service as well as purchase, taxes, and insurance. :cheer2:

 

I worked with one consumption test comparison that it would take 900 years at the fuel saving on 15,000 miles a year that the BMW got over the Prius to recover the BMW premium. That would be even longer if you did just a tiny bit more urban driving than in the test. If the ratio was reversed you would never get your premium back!!

 

Let's see...

Beat the Prius by 1.8mpg. Okay. Now the cost per mile of each...

Prius: 45mpg * $1.75/gal = $0.038/mile

Diesel: 46.8mpg * $2.42/gal = $0.052/mile

Yea.... the Diesel won alright!

 

*yawn* a Tesla leaves every Beemer lying upside down in the dust and uses less fuel. It's a good thing that there are German and American POSes priced for people who can't afford a real sports car.

 

Isn't it a good thing when there's another vehicle added to the list of Good-MPGs, regardless of what brand it is?

Why chide it because it isn't a Prius?

 

emissions. It's the emissions that too many diesel supporters seem to negate. This is why the Prius stands alone with more efficiency and less pollution. Why is that cost never factored in? Stand behind your diesels (literally) and tell me which vehicle you'd choose.

 

As far as emissions are concerned, the differences are really in the noise level, especially if you consider the far higher evaporative emissions of gasoline, which the gasser supporters tend to ignore.

Gasoline vapors oxidize in the atmosphere to formaldehyde (a carcinogen) and eventually to organic particulate matter (secondary organic aerosols - SOA). Studies have shown that ambient ultrafine PM (particles with aerodynamic diameter of less than 100 nm (PM0.1)) are overwhelmingly composed of organic carbon (e.g., SOA), not elemental carbon ("soot"). This pollution is not accounted for in the "tailpipe" emissions.

 

Except the U.S. Prius has a closed system so the evaporative emissions are going to be less than diesel without such a system. (I would rather ditch the bladder tank, but that is what it is there for.)

 

Upon what are you basing this assertion? I'm not specifically referencing the Prius anyway, just gasoline vehicles in general.

Even then, if you look at the CARB certification data of the LEV II PZEV Prius, the evaporative emissions from the vehicle itself exceed the "tailpipe" HC emissions ( http://www.arb.ca.gov/msprog/onroad/cert/pcldtmdv/2009/toyota_pc_a0140628_1d5_pz_hevge.pdf ). The Prius' bladder tank is effective in that it reduces evaporatve emissions during refueling to zero (at least according to the cert data). However, there are still measurable evap emissions from running loss (0.01 grams/mile) and three-day diurnal emissions (evap emission while a vehicle is just sitting in a driveway or garage).

Plus, you have the evaporative emissions from the "handling" of gasoline along the supply chain, which are not accounted for in the vehicle certifications. Diesel fuel is relatively non-volative, so these evap emissions are trivial compared to gasoline.

 

I stand corrected on diesel fuel's vapor pressure. Funny though, I've smelled enough of it to realize it is far from trivial in reality. Ironically, less regulatory concern about its evaporative emissions might have something to do with this.

However, we are discussing the Prius, not the supply chain or another gasoline operated vehicle.

Good luck applying more lipstick to the diesel pig.

 

Then how do you explain why peer-reviewed source apportionment studies have apportioned between 50% and 80% of ambient HC (and that ALL ambient HC, not just anthropogenic) to gasoline exhaust and gasoline vapor while diesel accounts for between 0.2% and 2%?

The Prius still uses gasoline. According to the USEPA (AP-42), 7.6 POUNDS of evaporatve emissions are produced in the supply chain for every 1000 gallons of gasoline throughput. So that means in 46,000 miles of driving (assuming the fueleconomy.gov mileage of 46 combined) the Prius is responsible for 7.6 pounds of evapotaive emissions (3447 grams). That's 0.075 grams/mile (it's certified @ 0.009 g/mi "tailpipe").

Meanwhile, according to AP-42, 0.0432 pounds (~20 grams) of evaporative emissions are produced by diesel fuel per 1000 gallons. Therefore, the US-spec BMW 335d is responsible for 0.00068 g/mi @ 29 mpg (CARB certified 0.023 g/mi "tailpipe" - http://www.arb.ca.gov/msprog/onroad/cert/pcldtmdv/2009/bmw_pc_a0080247_3d0_l2_diesel.pdf ).