MIT: To Get Better Gas Mileage, Cars Need Less Power, Weight
In recent years, the quest for high gas mileage has become an important factor for new car buyers, automakers, and legislators alike.
But has gas mileage really improved over the past 30 years, and what do automakers really need to do in order to ensure their cars meet tough new Corporate Average Fuel Economy targets by 2025?
According to MIT economist Christopher Knittel, the answer is simple: maintain the same rate of automotive technological innovation we’ve seen since 1980s while simultaneously replicating the average weight and power of new cars sold 30 years ago.
Has Gas Mileage Changed?
Thirty years ago, the U.S. was recovering from the second major oil crisis to hit the nation.
With gas prices still high, high gas mileage cars like the 1982 Volkswagen Rabbit proved a popular choice for those wanting to save as much at the pump as possible, while older cars like the original 1973 Honda Civic offered used car buyers a way to avoid high fuel bills.
Both of these examples, along with many other older cars, are capable of producing gas mileage rivaling or even beating modern-day fuel sippers like the 2012 Chevrolet Sonic.
In fact, if you look at the change in gas mileage between a car made in 2006 and 1980, there’s an average fuel economy increase of just 15 percent, while average curb weights have increased by 26 percent, and power by a massive 107 percent.
Larger, Faster, Safer
Why the disparity between power and weight increases and fuel economy?
It’s simple. Cars have got a whole lot more complex. Thirty years ago, satellite navigation systems and complex entertainment systems were unheard of. And electric windows, crumple zones and airbags were considered high ticket items on luxury cars like the 1981 Mercedes-Benz S-Class.
As more safety and entertainment features are added to a car, so the weight increases. In order to compensate, automakers have had to increase engine power.
What we’ve been left with, Knittel explains, are larger, faster, safer cars whose engines are actually 60 percent more efficient than engines produced 30 years ago. But because modern day cars are so much heavier and require more energy to move, any gas mileage improvements in engine design are not as great as they could be.
The Solutions
Although Knittel praises developments in fuel injection technology, engine control systems, lighter engine components and variable-speed transmissions his report, he also concludes that making cars smaller and less powerful is the key to better fuel economy.
According to his own calculations, Knittel says automakers have already built engines that are technically capable of meeting 2025 CAFE standards, but need to reduce both the curb weight and power output of the average vehicle by 25 percent in order to transfer that gas mileage from the laboratory and onto the road.
In other words, Knittel wants cars to go on a diet, or go back to the same weight and power output they had in the 1980s.
In addition, Knittel advocates higher gas taxes, and a change in consumer preferences driven by governmental policy changes.
Incorrectly applied though, bad policy could make matters worse. “If you force people to buy more fuel-efficient cars through CAFE standards, you actually get what’s called ‘rebount’, and they rive more than they would have,” he cautioned.
The Reality
Thanks to developments in carbon-composite technologies, automakers have already started to make cars lighter. But a 25 percent drop in curb weight is a big challenge, especially if current safety and entertainment levels are to be kept.
And power? Academically, Knittel’s research makes sense, but we’re not sure the average car buyer is ready to give up the extra horsepower we’ve all become so used to.
We think a better solution lies in the world of plug-in vehicles, combining small gasoline engines with efficient electric motors to increase gas mileage and reduce emissions, but what do you think?
Let us know in the Comments below.
This story originally appeared at The Car Connection
Nissan Planning Camera-Based Accident-Avoidance Tech For Mainstream Models
Nissan, like several other major automakers, has for years been offering potentially life-saving accident-avoidance technologies like lane-departure systems, blind-spot warning systems, and forward collision warning.
Trouble is, those features are only offered on expensive luxury vehicles (in Nissan's case, in Infiniti models) and usually, at a steep premium. Since in most cars these systems rely on expensive radar sensors (which often to double duty for 'smart' cruise-control systems), they're usually optional, as part of pricey tech packages.
Compounding the issues in getting active-safety features out to the masses is that, as surveys continue to find, new-car shoppers are even today more willing to pay for convenience features than safety aids. Meanwhile, the IIHS found earlier this year, in looking at how systems on the market have performed, that accident-avoidance features could cut crashes by a third.
And the cost of radar sensors isn't likely to come down significantly in the near future.
The solution? Nissan has turned to a 'making do with less' philosophy—namely, drafting the cameras used in their Around View Monitors into higher-speed, active-safety use. With the help of sophisticated image processing, it's now possible to achieve pedestrian detection, lane-departure warning, and blind-spot warning features with just two wide-angle cameras—one in front, one in back.
Workaround for costly radar: high-end image processing
According to engineers working on the project, as part of what's termed the Multi-Sensing System, the image-processing demands of the device aren't much beyond what you might have in your smartphone—but even with the software at the level it is today, the combination of processing and the need for reliable, all-weather cameras would have made it cost-prohibitive just a few years ago.
In Japan for the Tokyo Motor Show this past week, we had a chance at Nissan's Oppama R&D center to sample firsthand how the system (equipped in a Nissan Dualis—essentially our Nissan Rogue) works.
Overall, it's surprisingly good; in ideal conditions, the camera-based system provides a warning as reliably as a radar-based one. However, engineers cautioned that in some weather conditions (rain, snow, fog), and at night, performance simply won't be the same. Considering that it may enable tens (or hundreds) of thousands of additional vehicles to get the technology, we think we can live with that.
Several lifesavers for hundreds of dollars, not thousands
The camera based system costs just a few hundred dollars per vehicle, and Nissan's plan is to offer it at about that cost, in a number of its mainstream vehicles—like, potentially, the Rogue, Murano, Altima, and even Sentra.
This technology has been developed within Nissan, not with a supplier, and it uses a proprietary combination of hardware and software, according to officials, so it could be a Nissan exclusive for at least a model year or two. Look for rollout beginning calendar-year 2012.
This story originally appeared at The Car Connection
TCC’s Ten Tips For Getting The Most Out Of Your Test Drive
Fifteen minutes might be enough time to quickly mouse-click through basic specs and prices and comparison-shop a few models; but it's not long enough to test-drive a vehicle that's likely going to be part of your daily life for years.
According to data from J.D. Power & Associates' Mystery Shopping program, the length of the typical test drive is a scant 10 to 15 minutes—barely enough time to make a few innocuous right-hand turns and back around to the lot. And despite all the time Americans spend on the Interstate, roughly half don't even include freeway driving.
In addition to assessing how the vehicle drives, performs, and fits your overall needs in such a short time, shoppers have another time-consuming (but potentially fun) task: putting the all technology through its paces. Interiors can now include sophisticated navigation systems, Bluetooth hands-free calling, portable audio interfaces, and complex screen-driven menu systems.
We've come to want to so much more out of our interiors than we did just a few years ago; besides safely following your driving inputs, today's models can function as mobile offices, go-anywhere jukeboxes, smart traffic advisors, daily planners, and even entertainers for the kids in back. And you want to test out those abilities when possible.
Whether you're shopping for something as ubiquitous as a Toyota Camry or as exclusive as a Bentley, making sure you get a long enough test drive, along with the attention you need when you have questions, is an excellent way of testing out a dealership as well as the vehicle. The more a dealer is willing to help with the shopping process, the more likely they are to pull through after the sale, when you might have special service needs. But remember, keep shopping separate from dealmaking; don't talk payments and prices on the test drive.
In the coming weeks, we'll be looking up close at a number of aspects—aimed at helping you get more out of your speed date with a new vehicle—in a series called Test Drive In Detail. In the meantime, here are ten must-read tips for getting the most from your test drive:
A Radar in Every Car: BMW, Daimler Team for Cheap Radar
No one has a crystal ball that holds the future of the auto industry, let alone the future of in-car technology, but two of the industry's biggest innovators have joined forces to help shape the future into one that includes radar in every car - or at least every segment.
A group of suppliers including Bosch, Continental and Infineon have joined forces with BMW and Daimler to help forge new ground in making radar systems affordable. The end goal of the project is to get radar-based driver assistance systems into nearly every car on the road, reports the EE Times.
Radar is already making huge inroads, with Toyota, Ford, Mazda and many other carmakers offering it already or working to bring the tech to market. But it's not easy to do it cheaply.
The project is planned for three years and a budget of 17 million ($23.6 million), allowing the companies to jointly develop mass-production radar sensors capable of covering distances as small as 2in out to about 820ft. With this much range, the radar units can help do everything from parking assist to adaptive cruise control and crash-prediction.
Cars like the BMW 7-Series, Lexus LS and Mercedes Benz S-Class currently feature a number of radar-based technologies, such as the radar-adaptive cruise control and pre-crash brake assist, so it's easy to see how getting this technology to the mass market could dramatically improve safety for everyone on the road.
[EE Times]
This story originally appeared at The Car Connection
