4 02 2010


Hybrids of the Present and Future

3 02 2010

BMW Vision VIDEO (Click here)

By 2016, automakers must to meet the federally mandated 35.5 mpg.  It has become conventional wisdom that hybrids will be key in reaching this lofty goal. The EPA’s Fuel Economy Guide 2010 listed that a straight averaging of new cars, pickup trucks and SUVs in the hybrid category yields only 29.2 mpg. True, the mandated average is a sales-weighted one, not simply a straight average. And hybrid cars alone are already there, at 35.6 mpg. Nevertheless, recall that the federal mandate includes all three classes, cars, pickup trucks and SUVs. An anticipated mix in 2016 would need cars averaging 42 mpg; pickups and SUVs, 26. Plus, there’s evidently a lot of hybridization yet to do.

Hybrids currently constitute a tiny proportion of our total fleet. In both 2007 and 2008, they made up a scant 2.2 % of new car sales. Their 3.6% market share in July 2009 was touted as the largest thus far. Is conventional wisdom at fault? Are hybrids our only option?

Let’s begin with the basics. A hybrid vehicle is propelled, directly or indirectly, by two separate means, a “heat engine” (in our context, one exploiting internal combustion) and an electric motor. The hybrid benefits from interactions of its i.c. and electric power. It exploits the strong points of each while mitigating their inherent shortcomings.

As examples, you can supplement the i.c.’s softness off the line with the electric’s instant torque. Use electricity alone in low- and moderate-speed, light-load conditions. Have the i.c. take on occasional recharging duties. Call on both propulsion means when required for acceleration.

Many of the category are full hybrids, capable of pure EV progress in some operating mode. Other mild hybrids employ their electric motors merely as a supplement of i.c. propulsion. Still other microhybrids exploit little more than electric start/stop and regenerative braking. Some examples among passenger cars already on the market are the Ford Fusion Hybrid, Honda Civic Hybrid, Honda Insight, Lexus GS 450h, Lexus HS 250h, Nissan Altima Hybrid, Toyota Camry Hybrid and, as something of the class representative, the Toyota Prius.

As referenced above, these class leaders only make up 2.2 % of new car sales in 2007 and 2008 and 3.6% market share in July 2009.  So the question remains: How do you make hybrids more appealing to the mass market?

The hybrids of the future are surpassing the hybrids of today in many ways.  Sleek design, advanced technological features, and fuel efficiency need to be combined for the mass market to jump on board.  One example of a concept car that combines all these features is the BMW Vision.  Simply put, it’s a 4-seat plug-in full hybrid with a turbodiesel engine and upward-pivoting doors. And it’s one packed with technologies that enable it to be both frugal and fast.

The Vision concept is propelled by three sources: two electric motors (one giving the car all-wheel drive in electric mode) and a turbodiesel engine (in front of the rear axle). The synchronous electric hardware can provide a continuous output of 80 horsepower and peak torque of 162 lb.-ft. via a two-stage, single-speed reduction gearbox. For that extra kick when passing, the motor can deliver 112 hp for up to 30 sec., or as much as 139 hp for 10 sec.

In back, the second electric motor resides between the mid-mounted turbodiesel and BMW’s 6-speed DCT twin-clutch gearbox driving the rear axle. This motor is produces 33 hp continuously (51 hp peak) and a maximum torque of 214 lb.-ft. Combined, the two electric motors can perform double duty in propelling the car or serving as regenerative powerplants to recharge the lithium-polymer batteries.

The Vision is a concept car that combines both current hybrid car technology and the technology of the future.  When interviewed by Road & Track magazine, BMW said that they are working with NASA “on adapting technologies used to generate power on deep space probes to generate electricity from the exhaust heat.” They hope that this technology will generate all the electrical energy needed to operate the vehicle systems.  They expect the technology to be used in 5 years.  Also, they believe that “predictive energy management” will be implemented.  By this I mean that future hybrids will have electronic systems that can be programmed to predict the driver’s drive cycle to maximize fuel efficiency.  For example, when a driver is going downhill in route to work the hybrid automatically schedules charging.

There is no official word of when the BMW Vision will be released.  However, one thing is certain:  This concept car proves that hybrid cars of the future can be as cool-looking and fun to drive as any sports sedan today.

Text taken from: http://www.roadandtrack.com/