If it is desired by consumers, then it does not require a government mandate.
Example: both Ford and GM have benched programs for new hybrid truck platforms, citing that solutions are technically and financially unattractive. A government mandate pushes them to build the unattractive solution anyway.
Some will say that this encourages Ford and GM to innovate. Yes, they must devote resources to develop a solution that competes against other companies forced to release unattractive solutions. At the very least, this diverts resources away from development that is attractive and desired by consumers.
Rather than a marketplace that reflects the cumulative values of consumers, we end up with a command economy. Engineers love a technical challenge, but step back further and realize that this is a liberty challenge.
I have no sympathy for the car companies. Clean diesels are incredibly efficient. An intercooled turbocharged diesel hybrid would blow these standards easily. And the technology is OLD technology. Sure cars will have to be smaller. We need to change the road infrastructure to get the small mass cars away from huge semis,etc. I drive an MB 190D that gets 35mpg on a gallon of home brewed biodiesel. In Europe you can get diesels that do exceed these 54.5 mpg standards.
On another point, get govt out of regulating things they don't understand. Diesels are currently regulated on particulate matter and they put those stupid post combustion units on them making them lose up to 30% of their fuel efficiency. All because some idiot didn't bother to think that what's really important is pollution per mile driven.
Increased infrastructure for bicycles and e-bikes would get many out of their cars and save so much money that we wouldn't have as much need for this kind of silliness from the government.
55mpg for a small passanger saloon? Easy. 1.2 ~ 1.5 turbocharged diesel engine. It's happening now in Europe. Take a look at the figures for EU market Volkswagen Jetta and Polo, Seat Octavia and Fabia, Citroen C3 etc.
I agree Charles, smaller turbo charged engines are a good small incremental efficiency gain by engine downsizing. Doubling MPG, would require a 100% efficiency gain by the drive train, if car mass/size is held constant. With a good gasoline engine already around/above 35%, that would require 70% if done with the engine alone ... well above the 58% thermal efficiency limit of a perfect loss free Otto engine. Where do we get the rest of the 100% gain without downsizing cars and trucks?
Active Fuel Management becomes less important with a smaller turbocharged engine, because the throttle will already be well off idle at road speeds, a diminishing returns problem when trying to combine both enhancements on the same engine. http://en.wikipedia.org/wiki/Active_Fuel_Management
From http://en.wikipedia.org/wiki/Turbocharger "Only 10 percent of light vehicles sold in the US are equipped with turbochargers, making the United States an emerging market, compared to 50 percent of vehicles in Europe that are turbo diesel and 27 percent that are gasoline boosted."
You're right, Rob. The engine enhancements -- features such as active fuel management and variable valve timing -- don't require much in the way of hardware. For the most part, it's a matter of electronics, software and a solenoid or two. Reducing engine displacemnt, however, is slightly different. The key to reducing engine size lies in the use of turbochargers. Turbochargers mean additional hardware and some extra cost, although some of that is offset by the use of smaller engines.
Beth Stackpole writes: "I just see this as a standard that pushes progresss. What's so bad about that?"
While a lot of us Geeks enjoy the leaps and bounds advances that electronics and computers make, while following Moore's Law, unfortunately the same doubling in performance every 18 months doesn't happen with mechanical systems which have hard bounds in thermal and mechanical efficiency. Otto Cycle ICE efficiency is bounded at roughly 58% for most cars, less friction, heat, pumping, and other losses that are well optimized in 35% efficient gasoline engines today. http://en.wikipedia.org/wiki/Thermal_efficiency
ICE's and automotive designs are subject to significant diminishing returns effects, after decades of successive optimization of nearly every part of the design for fuel economy. Every step past the last 20 years gets exponetially more expensive for smaller and smaller gains ... there simply isn't a free lunch here, as long as the emission requirements reduce efficiency.
Besides hybrids, the best we can do with ICE drive train efficiency is to switch to clean turbo diesels, and pickup about a 30% efficiency gain from the higher effective compression ratio, over Otto gas engines. VW Diesel Jetta's already are in the right range, without an expensive heavy electric hybrid. Unfortunately, there are a lot of environmentalists that hate diesels very strongly. And there is an NO3 emissions issue, that the EPA will have to relax.
Hybrids and EV's have a very difficult time with efficiency at slow speeds, especially serial hybrids and pure EV's, where electric motor efficiency runs below 50% at slow speeds ... like stop and go driving, and there is very poor kenetic energy capture for regenerative braking. Hybrids like the Prius have very small battery packs, trying to safe weight ... and can only capture a tiny amount of energy -- about 600watt-hours. Electric Motor efficiency decreases with increased torque requirements, so operation on hills is significantly less efficient.
As you increase battery capacity, so increases wieght, and a larger share of the battery energy is consumed to accelerate the battery weight. Kind of the same problem as launching rockets in space, where a small increase in payload, requires a significantly larger increase in propellent to leave the ground.
And both Hybrids and EV's dont' save the fuel needed for climate control and lights in both hot and cold weather, that becomes expensive during stop and go driving in commuter environments that affect more than half the population, at least half of each year.
Downsizing to unsafe smaller mini and micro cars remains the most likely choice driven by costs, that consumers will be forced to accepts ... and with that a lot of deaths.
Some environmentalists belive these regulations will be "Saving Oil for future generations", the real outcome is that we spend a very high cost to reduce US oil consumptions, while the rest of the world consumes the cheap oil that was "saved in Amercia" and use those lower costs to continue to undercut American living and manufacturing costs, sending even more jobs overseas.
So, my question is: is reducing US oil consumption, really worth increasing US automotive deaths, and leaving the US economy even further less competitive in global markets?
I see your point. It's that that last 10mpg isn't worth spending the extra dollars that might get you the next model capable of 54.5mpg when you have an older vehicle that comes pretty close. I suppose that's a valid concern on the part of the automotive makers.
The problem Beth, is that almost always, politicians strongly (and blindly) push measures like this one far over what is Feasible, Reasonable and Convenient.
Engineering is the art of carefully balancing many simultaneous factors in order to provide a solution. Engineering is almost always a compromise, the better, most well balanced one is often the most effective. Blindly or deceptively trying to elevate a single aspect above all on a complex system, is going to hurt several other aspects, remember the "Law of unintended consequences".
Lets all remember what happens when politicians invade the engineering and science fields, in a thriumphalist outburst of green (pun intended) proclaim determine whatever they feel is to be achieved, regardless of costs or worse.
An example: the absolutely stupid, myopic and counterproductive ban on incandescent lamps, procaiming that the CFL (Compact fluorescent Lamp) IS the way to go... Forgetting that CFL's contain sizable quantities of mercury (one CFL broken inside a bedroom SHOULD require a decontamination costing thousands of dollars, unless you don't mind your loved ones breathing mercury vapors for a long time!), have an absolutely worst Power Factor (less than 0.52 for the better ones), use a wide variety of non-reclaimable materials in their manufacture, have a terrible Colour Rendering Index (CRI) - typically 60 - 70, and among other disadvantages, cannot be used inside sealed or poorly ventilated fixtures, require several minutes to reach their full brightness, are damaged if subjected to frequent switching cycles... and not surprisingly, use a LOT of energy in its manufacture, and quite a bit more in their PROPER recycling.
But the brilliant politician gods have determined that the incandescent bulb is devil, and they had to kill them! (for an exhaustive, balanced and reasonable tehchnical discussion on the incandescent ban and CFL's, I suggest reading the essay written by a truly ingelligent human being, that happens to be a very good engineer from Australia: http://sound.westhost.com/articles/incandescent.htm#cchar
Another example: The serious problem of tin whiskers growth in electronic solders without any lead content, because of the insufficiently thought out "green" measure pushed by the European monkey politicians (RoHS, Directive 2002/95/EC), which is another example of twisted, tricky and stupid selective thinking: lead in electronic solders is banned, but only 2% of total lead use goes into the solders, most go to the car battery industry, and in a glaring show of hypocrisy, Cadmium telluride (CdTe) thin-film PV modules in photovoltaic panels are explicitly allowed by RoHS to contain cadmium, even though cadmium is restricted in all other electronics. The solar panel exemption was in the original 2003 RoHS regulation and it was further extended on May 27, 2011.
So to me it is clear that when a politician promotes a green measure, BUT imposes insufficiently revised goals, humanity ends up harmed (albeit a few selected companies could benefit).
I'm just imagining the safety, price, durability, repairability and freedom from problems that new vehicles will have to sacrifice in order to meet that kind of goal. On the other side, as an engineer, I would be more than happy to see true advancements, perhaps to a more realistic, less delusive-dream number.
That makes sense, Chuck. But with the limited sales of hybrids and EVs, most of the CAFE gains will come from traditional engines. Wouldn't most of the gains on those engines involve upfront innovation rather than the incremental costs of parts? Or, is there something intrinsically more expensive about the parts that would be needed for a high-efficiency vehicle?
Using a 3D printer, CNC router, and existing powertrain components, a team of engineers is building an electric car from scratch on the floor of the International Manufacturing Technology Show in Chicago this week.
In November, a European space probe will try to land on the surface of a comet moving at about 84,000 mph and rotating with a period of 12.7 hours. Many factors make positioning the probe for the landing an engineering challenge.
NinjaFlex flexible 3D printing filament made from thermoplastic elastomers is available in a growing assortment of colors, most recently gold and silver. It's flexible and harder than you'd expect: around 85A (Shore A).
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