Posts Tagged ‘BMW X6’


April 7th, 2010 Comments off

On my commute to work this morning, a Toyota Prius passed by me in the HOV lane.  (It wasn’t traveling at a high-rate of speed, so I suspect the throttle was not stuck open.)  The personalized license plate on the Prius read “H8 GAS“.  Although I could only see the back of the driver’s head, I’m quite certain his expression bore a certain degree of smugness.

The gas-hating Prius-driver obviously feels he is doing right by the environment by purchasing one of the most fuel-efficient vehicles available.  (I mean, he did go so far as to plaster the motivation for his good eco-deed on the back of his car!)  The irony here, however, is that this driver sat alone in his Toyota, taking advantage of the policy that’s in place in most major metropolitan areas that allow drivers of hybrid vehicles to travel in the HOV lanes regardless of the number of vehicle occupants.  Meanwhile, I was motoring down the carpool lane while seated on a bus – powered by natural gas – along with several dozen neighbors.  (Once disembarking from the bus, we all boarded a subway – powered by electricity.)

Now, I don’t want to fault the Prius driver too much.  Perhaps he had a good reason for taking up space in the HOV lanes today.  And he did, afterall, make a good vehicle purchasing decision from an environmental standpoint.  I do have to question his taste in license-plate personalization, however. It exudes the same self-righteousness as the stock broker whose plate says MONYMAKR.  Or the Christian’s whose plate says FORGIVEN.  …Or the urologist’s whose says GR8FNGRS

I also have to question the HEVs-in-HOVs policy that so many people exploit.  Much like Cash for Clunkers, the intent is a legitimate one (to accelerate the deployment of fuel-efficient hybrid vehicles), and it has been somewhat successful – many folks buy hybrid vehicles solely for the privilege of traveling solo in the carpool lane.  However, I cringe at the large number of single-occupant, HOV-traveling hybrid Ford Escapes and Toyota Highlanders I see – both reasonably fuel-efficient vehicles, but nowhere near as economical as many smaller conventional vehicles.  (God help me the first time I see a BMW X6 ActiveHybrid exploiting the rule..)

Don’t get me wrong – I’m all-in when it comes to promoting the development, manufacture, deployment, and market penetration of hybrid vehicles.  (In fact, that’s what I do everyday.  For my job.  For which I get paid.)  But perhaps it’s time to revisit some of the policies that were put in place to spur the HEV market, and instead focus on policies to promote public transit.  (Some places, like California, are starting to do just that.)  After all, if he hadn’t been able to drive in the HOV lane alone in the Prius, the Gas H8r may have been enticed to keep his conventional vehicle and make a few carpool buddies.

…Or even ride the bus – leaving him time to think of other ways to advertise how proud he is of himself.

Somebody KERS!

February 14th, 2010 Comments off

Last August, I posed the question, “Who KERS?” in regards to the limited success of the Kinetic Energy Recovery System employed in the 2009 Formula 1 season, and the elimination of the system for 2010.  Well, it turns out that at least one of the systems developed by an F1 team will in fact live on.

As recently described by AutoBlogGreen, Porsche is utilizing the Williams-developed flywheel-based energy storage system in its 911 GT3 R Hybrid.  The 911 GT3 R is the race version of Porsche’s bread-and-butter 911.  The hybrid system leaves the conventional 480-hp flat-6 powering the rear wheels untouched, while adding a pair of 80-hp electric motors to each of the front wheels.

Porsche 911 GT3 R Hybrid

Porsche has always done things a little differently than other automakers, at least with respect to the 911.  Instead of competing in the horsepower wars using 8-, 10- and 12-cylinder engines with massive displacement, they’ve continually developed their horizontally opposed 6-cylinder combined with lightweight (and often exotic) materials to maintain their competitive edge.  Until just over a decade ago, this engine was still air-cooled, in contrast to literally every other automaker’s water-cooled powerplants.  And even now, in a triumph of engineering over physics, Porsche still hangs the motor way out back behind the rear axle.  So it comes as no surprise that they’ve taken the less-traveled path of using a flywheel (instead of a battery) to recovery the energy from braking.

In the simplest terms, the system works by the front-axle motors acting as generators to convert the kinetic energy of the spinning wheels to electrical energy under braking.  The electrical energy is then converted back to kinetic energy at the flywheel (which is essentially another electric motor), as it spins at speeds up to 40,000 rpm.  Under acceleration, the flywheel then acts as a generator, converting the kinetic energy of its spinning mass to electricity, which is routed to the front-wheel motors, where it is converted back to kinetic energy to help power the wheels. (One thing I’ve often wondered in systems like this is – why all the conversions? You want kinetic energy to move the car, and with a flywheel you’ve got a kinetic energy storage system.  Seems like there’d be fewer conversion losses if you could skip the electro-part of the electro-mechanical system, and just connect the flywheel to the drive system by an intelligently activated clutch or viscous coupling.  I’m sure the hybrid system designers out there could give me countless reasons why this wouldn’t work, however.)

And finally, am I a hypocrite because I like this car so much more than the BMW X6 ActiveHybrid, which I criticized here?  Of course not.  BMW has taken a conventional fuel-efficient technology and applied it to a mass-market car solely for performance purposes, with almost no efficiency benefit.  (Plus, the X6 is ugly.)  Porsche, on the other hand, has taken an unproven fuel-efficient technology, and applied it to a limited production race-car as sort of a rolling laboratory to spear-head the development of this new technology, before potentially applying it to its road-going cars.

And although I (like many others) question the feasibility of flywheels as the energy storage solution for mass-market hybrid vehicles, people also once criticized the throwing-a-dart-backwards handling characteristics of the rear-engined 911.  And by most measures, Porsche has been successful with that effort…

Missing the Point

January 7th, 2010 Comments off

The fuel-economy of our nation’s light-duty vehicle fleet has been roughly stagnant for the past three decades, following a significant (but unsustained) improvement just after the Corporate Average Fuel Economy (CAFE) rules were enacted in 1975.  And although our cars’ fuel-economy hasn’t really improved, their efficiency certainly has.  We’re certainly moving around a lot more mass, a lot faster, on the same amount of fuel (per car) we were using 30 years ago. The problem is, all this technology packed into our automobiles has been engineered almost entirely to give us more performance (a 1980 Honda Accord had less than 80 hp; today’s base-model is approaching 200) and move us around in a lot more luxury (with a resulting heft of 3200 lbs for today’s Accord, a gain of a half-ton over the 1980 version) than we ever thought possible, at the complete expense of fuel-economy.  (I know, it’s a result of market demand…  But the best marketers are experts at selling us what we don’t need.)

These days, hybrid technology seems to be the solution to significant increases in fuel-economy, as it becomes ever more difficult to squeeze further efficiency improvements from conventional powertrains.  But BMW has taken a different tack with their ActiveHybrid X6.  Touted as “the world’s most powerful hybrid,” BMW starts with a 4.4-liter, 400 hp V8 internal combustion engine – which, until recent years, would have been enough of a beast to power anything but vehicles of near-supercar status – and integrates it with not one, but TWO electric motors totaling an additional 174 hp.  And sure, the combined 574 horses will be enough to provide incredible acceleration in this nearly 3-ton mammoth, but … what’s the point?

2010 BMW X6 ActiveHybrid

2010 BMW X6 ActiveHybrid

The X6 ActiveHybrid starts at a base price of nearly $90k.  At that price-level, you could almost have a Tesla Roadster, or one of the other upcoming EVs or PHEVs with phenomenal performance and actual environmental benefits.  Granted, the X6 will carry a little more gear than a Roadster.  But, it’s ugly – no matter what powertrain is under the skin.  The X6 looks like the answer to a question that nobody asked.  And while I’m sure it, like all BMWs, offers a driving experience more exhilarating than the majority of other cars on the road, I can’t help but think of it as a caricature of a Honda CRX.

I hope automakers don’t repeat the trend of the past 3 decades, by following BMW’s example of continuing to utilize efficiency-improving technology to increase performance while sacrificing potential fuel-economy benefits. Fortunately, due to the recent and long-overdue increase in CAFE standards, this trend may be thwarted.  At least, as it was in the 1980s, temporarily.