Toyota's Direct Injection Four-Stroke Superior version (D-S4) engine combines direct injection (which injects fuel into the combustion chamber) with port injection (which injects fuel into the intake ports). It controls the two types of injectors in accordance with driving conditions. Under heavy load, direct injection is employed. Under medium or high load, both types are used. In the drawing on the left, the engine uses both types of injectors (port injection is marked as "1" at the top). On the right, the engine uses direct injection only. (Source: Toyota)
Wow, Chuck. I am duly impressed. I didn't realize there was such a wide swath of technology and innovations underway to address the 54.5 CAFE standard mandate. As you well noted, the focus tends to be on powertrain technology, yet there are many other places, many probably not considered, where auto OEMs can squeeze more mileage out of their designs. I particularly was impressed by the so-called "little things"--the improvements to making the wiring systems lighter and the flaps on the Chevy Cruze for aerodynamics. Very, very interesting stuff.
I agree, Beth. There are a lot of little technologies that eke out a few tenths of an MPG. The technology that will have the biggest impact, and will be most widespread, I think, is start-stop. Over the next ten years, we'll be seeing that on huge numbers of vehicles.
Beth, I too am exited that these technologies are being explored and implemented. I am not surprised, because many of these innovations are not new, certainly start-stop technology is something that is not new and could have been implemented 20-30 years ago (has been on the Prius for 15 years). My hat is off to DN and Captain Hybrid for bringing some of the new technologies to light, we have heard too many excuses as to why we can't reach CAFE standards, and not enough examination of technology and innovation. These are only 19 ways (there are many more existing) that can be used to increase mpg ratings, not to mention ideas that have not even been thought of yet. Interesting that none of these ideas force cars to be smaller, and they don't even include hybrid technology. Coupled with hybrid/electric technology, the 54mpg standard should be met easily if we stop fighting about it and start engineering.
The 600 ib gorilla is reliability. If most of these technologies ever fail in the field, the cost to repair will exceed the fuel saved. The energy required to make the repair parts might even exceed the fuel saved, a total false economy.
One in particular I would avoid like the plage is the aluminum wiring. It will be a disaster. Aluminum is NOT suited for wire.
Manufactureres must remeber the cost of poor reliability is loss of market share, always.
I agree that added complexity is not the answer. That is why I am skeptical of hybreds. They more than double the possibibility of major component failure, and double the weight of the propulsion systems.
But some some ideas, such as regenerative braking, are simple and could easily reduce fuel comsumption by half. If brakes enaged an air compressor or flywheel, that energy could be used over and over again instead of being wasted, and it is not a very complex system.
And I agree about the hazards of aluminum wire. It was tried in homes in the 1950's, with terrible results. If one wants to reduce weight from wires, the easier solution is just to increase voltage from 12 to 24 or 48, because then wires can be extremely thin, and still carry the same wattage safely.
I like a lot of these ideas, but I agree that using aluminum wire is scary! Millions of homes were wired with aluminum wire in the 1960's and early 70's, until electrical fires became epidemic in those houses, resulting in millions of dollars in lawsuits due to the property damage, injury and deaths those fires caused. The problem was when connectors and devices made for copper wire were connected to the aluminum wire or when copper and aluminum wire were spliced together, causing galvanic corrosion at the connections. As the joints began to corrode, the resistance of the connections increased, raising the temperature of the connection until the insulation failed, resulting in a short circuit and fire.
This wouldn't be as much of a problem for the OEM, as he could prevent the use of mixed-mode wiring, but for mechanics in the field, it would be a disaster, trying to determine what kind of wire was in the car before making electrical repairs. It would be even worse if they used copper wire in place of aluminum to make the repair, only to have the car catch fire a few months later!
It seems odd that simple old common knowledge is being ignored though. Such as we have known for decades that a simple air dam at the bottom of the front of the vehicle will greatly reduce air drag from the bottom of the vehicle. But no one builds in air dams on a regular basis, except for cars like Alfa Romeo, Porsche, etc.
Yes, I agree. Things like more gears, higher reving, variable supercharging, and direct injection to eliminate pre-ignition, would allow a smaller and lighter engine to still have sufficient hp potential, without all the extra weight of a larger engine. Deactivation does not make the wasted weight of the deactivated cylinders to go away.
The real gorilla in the room is the driver. I don't know what kind of efficiency improvement optimal acceleration and decelaration would garner, but I bet it's significant. I'm always amazed at how many people gun it at the green light only to hit the brakes 500 meters farther down at the next light.
As for the technologies presented in this article, it looks like the engineers are doing their part.
The real gorilla is simply size and weight. All these admirable technologies simply allow us to extract incremental improvements in efficiency but as long as we use heat engines we are stuck with fundamental physics and the Carnot cycle. The physics of physical size on aerodynamics is pretty much fixed for practical vehicles that people can use for real transportation. Weight is the other one. There will be compromises. Vehicles will have to get smaller and lighter. Cutting weight is where the money is. Vehicle manufacturers have done very impressive work on making engines more fuel efficient, reduced emissions, and have kept performance pretty reasonable. I remember the gutless wonders that came out the the late 70's, early 80's. Chevy Citation anyone? Celebrity with the iron duke 2.5L? K-car? Remember throttle body fuel injection? <<shudder>>. Some of these cars had 0-60 times measured in minutes.
Cars are going to become more focused in their marketing/deployments. For instance, if you do mostly highway driving or country roads with few to moderate stops, a hybrid car becomes a liability because of the extra weight and complexity. Hybrids and start-stops make good sense for city cars and lots of in-town driving but their advantages disappear on the open road. Light weight, good aerodynamics, and simple, fuel efficient engines will yield very good results when the driving is biased towards the open road. Parasitic drag is another area that will yield significant improvements. Power steering and water pumps are prime for electrical replacements.
With all the customer and market interest in fuel efficient vehicles, why does the government feel it needs to drive this market? I can understand to some degree safety and emissions mandates as those are less tangible to the average consumer. But mileage? That's on virtually every one's mind.
I agree that mpg is on everyone's mind when gas prices go up, but not ahead of time when it could make a difference. We have had over 3 major gasoline shortages and price spikes in the last 40 years, and each time US auto makers were totally unprepared, nearly failed, and required expensive taxpayer bailouts.
The rest of the world has also already tried the free market, and it has always failed when it comes to vehicle mileage. Everyone only wants everyone else to use less gasoline, so that it will be cheaper for their beheamoth. So I see no way around regulations at the means.
If vehicle buyers had any sense at all, they would not be buying silly, heavy, fragile, and expensive things like power seats, power windows, power locks, remote start, keyless entry, etc. Although car makers have to take part of the blame for not being honest about how these things harm reliability and mileage.
Just saw an interview with Ford CEO Alan Mulally, on the current situation with Ford and it's future. Interestingly, he states that fuel consumption is the NUMBER 1 factor in buying cars nowadays. Many other interesting comments from him about the use of Aluminum, and how Ford has now paid off it's 28 billion loans by producing better and more fuel efficient cars, thank you Obama. I'll let you listen to the rest... http://www.impomag.com/videos/2012/09/mulally-fuel-efficiency-drives-car-sales
Uhg, I got to this party late, but I see the same tired arguments continue to play out. The free market failed? Nay, we abandoned the free market and failed.
The argument is made that the free market failed during gas shortages. Can we not consider what role regulations play in creating shortages? Does not the government already manipulate the places that we can seek and extract resources, the number of refineries, and the formulations of fuel that may be sold at different times?
California - posed with a gas shortage - is looking to remove the formulation regulations (temporarily). They say that it won't make much difference in air quality, which if true, begs the question, "then why burden the marketplace with such onerous regulations?!" Were they being dishonest about the value of the regulations when justifying them or now that they are inconvenient?
Taxpayer bailouts of failed business models ... are you stretching your free market model to suggest that this somehow fits? In my world, it is called a command economy when the government controls the levers and switches of business. The free market allows for new management to buy out the resources (factories, labor, etc.) and operate under a new business model.
I do not disagree with your priorities on what is important in a car. I recognize, though, that I cast one vote with my purchase choices. Feel free to lead the charge in educating consumers, but do not blame manufacturers for building what people want to buy.
The consumers have always wanted better mileage, but they don't have enough influence on manufacturers because the profit margins are much thinner on inexpensive cars. The makers sell fewer luxury cars, but the luxury cars set the standards because their profit margins are better than 5 good mileage cars.
So market pressures never work. The car makers have failed to adapt to better mileage cars 3 times now, and each time the tax payers had to bail out the car makers. That neither works nor is fair. So regulation to make them produce better mileage is the only alternative. If we let the car makers keep failing, the whole country will fail.
Car makers are not making what people want, but what is most profitable in the short term, for them. And they ignore the long term, cyclic gas shortages, and the fact the short lived, delicate stuff they pack new cars with, are going to anger buyer is about 5 year when it all starts to break.
My 1982 Ford Escort Wagon got 40 MPG and I never had a complaint about its accelleration or responsiveness. It took a pretty steep hill to bog it down (I did know one such). Then again, I am a pretty conservative driver. It wouldn't surprise me if some of the "stomp-stomp" drivers would complain.
The government needs to set targets because a free market will progress very slowly on its own. These new technologies are expensive to engineer / design / and implement, and cause reliability / repair cost issues. Consumers gravitate to low cost which is why electric vehicles with extended ranges are not popular....they cost too much. This is a lot of very little improvements, without a mandate, it would be hard to get excited about any one of them. Even with all of these, the automakers will likely need to hope / push people move to smaller cars. I would have bought a hybrid Toyota Higlander 7 years ago but the $10K premium did not seem like a good payback at the time. If the price of new vehicles skyrockets with this new mandatory technology, I will vote to keep my older cars longer and longer.
If this country is serious about improving fuel economy then we need to invest in things like traffic circles and timing for stop lights. It's no secret that city fuel economy is nominally 30% less than highway economy. btwolfe mentions start/stop habits ... the best solution is to avoid the stop altogether since it takes far less fuel to maintain velocity than to accelerate to the same velocity from a stop.
Finally! Someone else sees this as a big picture issue. Traffic patterns in this country have severly degraded over the last 30 years (since the big recession in the '70s). Traffic lights have reverted from sensor oriented back to timed lights, and they are no longer timed together. Traffic circles, or round-abouts are non-existant. Stop and go traffic is a problem the government needs to resolve. Not tearing apart working, flowing interstate exits and replacing them with traffic light ramps that stop traffic as they are currently doing in my community. We seem to be going backwards in this area.
Absolutely right. The more efficient the car, the more carefully the driver has to drive to extract this performance. A 10mpg car is not going to see too much degradation in performance when the driver drives badly. Hybrid and high fuel efficiency vehicles will see dramatic reductions in fuel efficiencies by poor driving technique. The car must be intelligent enough to be able to help these poor drivers while not compromising safety.
Based on the following government site, bad driving habits can affect milage as much as 33%.
Although I'm not an agressive driver so my milage wouldn't improve dramatically from an optimal pattern, I can hardly wait for autonomous vehicles. Let the machine do the driving! Traffic lights won't even be necessary.
I suspect even our most optimistic forcasts of improved traffic flow and milage will ultimately prove to be pessimistic.
Talking about automation, what we need also are more intelligent cruise control systems. For electrics/hybrids it makes a big difference if power is constant rather than speed is constant. Allow the cruise control system to slow down the car on climbs and speed ups on descents. With a definable window of speeds for the cruise control, highway efficiency can improve further.
I have found that driving habits (or shall we say "technique") does make a significant difference.
My own commute is about 50 miles one way and I ran a simple experiment over the course of a couple weeks to see how far I could stretch my mileage. My drive is about 35 miles at highway speed ann 15 miles in heavier/slower traffic. Driving normal, I get about 32mpg over time. However, while driving with the intent to increase mileage, I was able to approach 39 to 40mpg. This was done by slowing down from 75-80 to 65-70mph, staying within "drafting" distance of other vehicles, avoiding hard accelerations, and popping the tranny out of gear to coast whenever possible.
We have already done the studies and found the solution as well. The thickness of the wire requirement is based on current, not voltage, and for a given work, one can just increase the voltage, and the current and wire size reduces propotionally.
So if you want half the wire weight, just increase the voltage from 12 to 24.
There is no reason not to go to 48 even.
The added advantage is that then it will be much easier to provide clean 12 volt DC for electrical components that have great difficulty with dirty 12 volt systems we have now.
We pulled the wiring harness out of a 90's Thunderbrid driver's door and it weighed 35lbs!!! We really need to go to 36vdc nom power to run acessories, etc to reduce weight, copper use along with at least start/stop tech to cut the pure fuel waste.
Present cars only get 7% of the fuel's energy to the road so by getting these parasitic loads off the engine alone can increase mileage 35%.
Also running just 1 power circuit with control modules at each load really cuts copper/wiring weight, costs.
Of course the big weight loss comes from getting rid of metal and going to composite body/chassis like the GM UltraLite and Toyota X-1 showcars.
Actually motorcycles are much safer than cars. They have far fewer accidents, mostly because they are so manuverable they can easily avoid them. Same is true of smaller cars. And in fact, if you are in a one car accident, small cars are safer, because it is the weight of the back end of the car that tries to crush the passenger compartment. Trying to make cars heavier so that you kill others instead of just making all car lighter and safer, makes no sense at all. If all cars are lighter, there will be far fewer deaths.
On a motorcycle you are only allowed 1 accident and you are dead. If all cars are lighter and trucks still weigh 100,000 lbs. the danger still exists. The weight is required to make a safety cage around the occupants so when the 100,000 lb. truck hits you and you bounce down the street the vehicle remains intact instead of crushed like an egg. If the cars are going to be weigh about 1000 lbs then trucks should be downsised to about 25,000 lbs. maximum also.
I have survived several motorcycle accidents. Apparently, I was "allowed" more than 1 accident. However, I get the point: cars (for most people/situations) are safer.
And, yes, more mass will increase your chances of survival in a crash.. but not because of a stronger cage around you. It has to do do with rate of change in velocity (think bug vs windshield for mass differences), crush zone size (de-accel time/distance) and occupant containment (seat belts). Race cars drivers have survived crashes in cars weighing less than 2,000 lbs - hitting brick walls (straight on) while traveling in excess of 150 mph. Numerous times. It had little to do with the additional mass of their "cage" (or even use exotic materials).
Regardless of this, it is not likely the payloads on 18 wheelers will be reduced to reduce risk to other motorists - there will never be the "political will" to do this. 100,000 lbs against 1,000 lbs or 3,000 lbs - the odds have not changed much with additional 2,000 lbs - the smaller vehicle is going to lose, big time. The only change: chances of hitting a car of equal or smaller mass. And if all cars are lighter, the odds have not changed. The reality is likely to be something between the two extreme examples - a slight increase in risks compared to the avg car on the today.
Trucks are irrelvant because nothing is going to survive a head on with a truck. Your only hope with a truck is to avoid a head on, and the smaller your vehicle, the easier to manuver and avoid the truck.
Safety cages are easier on lighter vehicles. Dune buggies are easy to make a safety cage for because they are light. If you had to make a safety cage for a big truck or even a Cadillac, it would be essentially impossible. The heavier the object is, the worse the strength to weight ratio. There is no way around the laws of physiscs. That is why an ant can lift 100 times its own weight, and we can't. We are too big. Small cars are inherently stronger.
The only problem is when 2 vehicles collide head on, then whomever has the greatest mass, will destroy the other vehicle. And the solution to that is not have head on collisions, or try to make all vehicles smaller.
Respectfully, cages are not that different between vehicles. You only protect the passenger compartment. In fact, "dune buggies" or "sand rails" have a bit more expensive cage since the cage is also their main structure (chassis).
I agree with you that for this discussion the focus should be on collisions between passenger cars, including light trucks. Collisions with large trucks have been and always will be catastrophic at medium to high speeds.
Dune buggies can easily take high speed roll overs with no problem or damage to the roll cage. If you used the same material to make a roll cage for a large luxury car, it would never hold up. It could not even take the weight, much less impact.
The Smartcar is an example of how the smaller a vehicle gets, the greater the strenght to weight ratio. Another was the old aircooled VW, which had amazing strength to weight ratio advantages, and is why it is still the basis for most dune buggies. When you examine larger vehicles, like Cadillacs or limosines, you find that they are weaker in all aspects, because of all the extra weight. It is not possible to scale up the strength to keep up with the weight increases caused by the strengthening attempt itself.
Just examine actual accident damage. You will find with heavier vehicles, there is often total penetration of passenger compartments, with things like side intrusion, etc. While with lighter vehicles, the main structure tends to stay more intact, and the danger to the passengers is more from whiplash as the vehicle tends to bounce off of impacts.
Or you can just study the animal kingdom to see the physics. You won't see animals larger than the elephant on land, because they simply exceed the practical strength to weight ratio. While anyone who has tried to crush a flea knows how difficult that can be.
Yes you would use a heavier gauge steel, but 8pt roll cages for SCORE trucks (not unlimited class) and dirt track late models dont' cost too much more than a dune buggy frame. Same basic design but the steel is gauged to the application considering weight and potential speeds (F= MxA).
I was just trying to point out that the cages are similar in size and construction with only the material cost being different. I wouldn't think the difference would be more than 10% - 20% of the cost.
I would think that a roll cage integrated into serial production of a vehicle would only add a couple $K to the price with a varience of a few hundred $* for vehicle size.
* - Disclaimer, I will not sign up to provide roll cages at these prices and am not responsible if someone who knows more says I am wrong.
Think about the liability of that 300 lb bumper? If you are trying to take a tight turn on rain, snow, or ice, isn't that bumper going to make you want to keep going straight? And when you have to stop quick, isn't that bumper going to want to make you take a longer stopping distance? Even accelerating, that bumper is going to be working against you. Then if you do have an accident, what good is that bumper going to be if you hit an immobile object? If you run into a concrete wall for example, that bumper is not going to absorb any impact, so does you no good at all. In fact, the back bumper is likely of equal weight, and is going to try to crush the passenger compartment onto the already flattened front bumper.
If you think about it, I think you will discover that most of what people think about vehicle safety is a myth, deliberately designed to sell larger cars that are more profitable. Areas like Europe and Asia that have always had much smaller cars, simply have much better accident survival rates than we do in the US, because of our larger and more dangerous cars.
The bumper really works good on deer. I don't know about elk, horses, or cattle. (I hope I don't ever test that.( But yes, I have to obey the laws of physics and go slower sometimes. Not as slow as a redi-mix truck but, slower than a light car might travel.
"As long as the safety cage is strong enough" works for me but what can it be made of to survive being squeezed between a row of cars and an one or two 100,000 pound trucks in a typical chain reaction accident? The impact speeds may not be real high but the crushing forces are.
I wonder how safe the Datona 500 would be if they had 30 cars and 6 double trailer trucks racing around with loads scrap metal and wood chips at the same time? In real life the truckers are always racing against time and money and both their following distances and tempers can be pretty short.
I think that anything smaller than my 4x4 pickup is just a metal coffin looking for a spot to be buried. Even a 7000 pound truck is probably a bit light for safe road use. I should probably consider installing a 500 pound safety cage.
Absalom: A heavy safety cage does not make a vehicle safer, but makes it more likely to lose control. And safety is from being able to maneuver and avoid collisions, not being able to withstand semi truck crushing. Smaller vehicles are inheretly stronger per weight, and therefore safer.
While direct injection costs more because of the high pressures needed, it can be exrtremely efficient. That is because it eliminates pre-ignition, ping, and knock. That means compression ratios can be increased dramatically, getting much more HP out of the same fuel combustion. The need for premium gas is also eliminated.
It also brings back the potential for going back to 2-stroke engines, that can get twice the HP for the same engine weight. With direct injection there is no mixing oil and gas or chance for excape of unburned fuel.
David: That's quite the claim. Ten years? No fossil fuels. I'd be happy if you were right, but . . .
. . . I remember Popular Science articles in the 70's touting the flying cars we all would be driving by the turn of the century. :-)
As for replacements, I'm good with #1. I think batteries will make incremental improvements over the next several decades.
As for #2, I must have had a Rip Van Winkle moment, and forgive me, I have never heard or read of an inert gas plasma motor. Any links to where the reader might learn more about this technology?
And #3, well, I'd be happy if they could sustain and control hot fusion for more than a femtosecond or so. I understand that if you set a cold fusion reaction cell outside during the day, it does get warmer. Commercializing that may have a few hurdles to overcome.
Head on collisions with anything are pretty final. Hit from behind and run into the guard rail are the threats I've experience from trucks. I suppose a good crush zone helps protect you from the first and a .44 mag handles the second. I still prefer something in the 8000 pound range for general use.
I think the real solution to the dangers of trucking is to go back more to rail, which not only uses less fuel, but could even be put into tunnels for safety and asthetics. In tunnels they could use electrical rails without danger, and then rely more on things like hydro-electric or solar as an energy source. Trucking was never a really good idea, and was only sold to us by oil companies.
The rail lines in LA running from the port to the rail yards close to downtown were "trenched". It relieved a lot of congestion and accidents caused by long container trains having to use grade crossings, and also reduced the need to move containers by truck from the port to the rail yards: http://en.wikipedia.org/wiki/Alameda_Corridor
But, there will always be a need for trucks between distribution centers and the local supermarket, Walmart, etc. There will probably be a lot of resistance to building rail yards and distribution centers in suburban communities.
Andrae Rossi's 1MW E-cat has recently received SGS safety certification for industrial use. One unit sold and delivered to an unknown military client, 13 on order pending certification. Several other companies plus US Navy and NASA are within a few years of commercially viable versions of the tech.
A far better choice than going to the 36 volt (42volts) systems would be TO GET RID OF a whole lot of those stupid things that need so very many wires. We do not need an air conditioning system with three microprocessors and two digital displays, and two processors for the 15way adjustable seats and mirrors. The list goes on and on, and the fact is that the majority of added items don't contribute to good mileage or to occupant safety. They are features that drive up the cost, both to purchase and to repair. Unfortunately they do add weight and mass and so they reduce economy instead.
The high pressure gasoline injection system is interesting, but who is going to service them? and how many will be injured and killed by the high pressure fuel systems? Really, 20,000PSI and even just 10,000 PSI are dangerous pressures, able to send a fine jet of fuel into any of a number of areas where it can do great damage. Working with those pressures IS different and it DOES have a new set of hazards, not to mentionalso a whole new set of problems not yet discovered.
And the high voltage system went the way of independant modules and digital control with the three wire bus, power, data, and ground. It seems that the system was a solution in search of a problem, and the benefits of having all of those parts on one control bus were not able to outweigh the problems experienced in making it work. So now in the car there may be two modules, one for the drive system and one for everything else. My complaint is that when the module fails, which is six months after the warranty ends, it can't be repaired, and the replacement costs $750, if you can get one. And the modules are potted so that they can't be repaired, and all of the failure prone big ICs are custom units that not even Bill Gates could buy, because repair parts are not available, and never were available. So pay $750 and wait three weeks to get your repair part.
So getting rid of the wires by going to 36 or 42 volts won't solve any problem, it will cause many more problems.
I agree with your thoughts on 42V, William K. It's truly amazing to look back at that period 12 years ago and see how the auto industry, engineering societies and trade magazines were ballyhooing the 42V idea. Now it's gone, and we don't hear a peep about it anymore.
The 42 volt systems would have been needed for the electrically pre-heated catalytic converters that some idiots wanted to mandate, with the intention that preheating the converter would result in instant conversion. and would eliminate any startup emmissions.
The problem was, and would still be, that it takes a lot more power to pre heat the converter than it does to crank the engine.So dead battery problems would happen a lot more than they do now.
When I was working for Analogy (now owned by Synopsys), we were helping Volvo design for 48 volt systems for trucks.
It was not to heat converters or power busses.
It was to cut the weight of conductive wires by 2/3s, and to allow for a clean 12 volt DC source for microporcessors. The higher the voltage. the less amperage you need for the same work. So higher voltage allows much thinner wire. And you have to have excess voltage if you want a clean result.
It is not a new idea, difficult, or a problem.
The military spec has been requiring 24 volts for 50 years.
The higher voltage systems for trucks and the 24 volt DC systems for military vehicles are for special uses. Military vehicles often had radio transmitterts and receivers, and the radio equipment in the tube type era could not run reliably on a 6 volt system. The 24 volt systems were for performance as much as anything else. In the trucks, the larger engines, especially the diesels, take a lot of power to crank. Also, trucks have a lot more lights than cars do.
There certainly was a push for the preheated catalytic converters about a year before the 42 volt systems were announced, so I see some cause and effect there. WE are all very fortunate that the preheated catalyst idea never took hold, since it would have been a functional disaster of embarrasing proportions. Just think about drawing 1500 to 2000 watts from your car battery for two minutes before you were allowed to crank the engine. With a new battery and a good electrical charging system it might work most of the time, but just try it on a cold winter night with a year old battery.
Fortunately rational thinking prevailed, and the beast was repelled.
Of course, there did turn out to be quite a few other challenges to making a 36 volt system work on common passenger vehicles. There were problems with light bulbs, switches, solenoids, and relays and some other components.
The 36 volt system is a poor choice because of the other types of problems, including poor lamp life and increased contact burning.
The way to get rid of the excess wiring mass is to get rid of the excess wiring, which would mean getting rid of all those accessories that have all those excess wires. The entire wiring harness from my 1965 vehicle could be held in one hand at arms length, including the battery cables.
The ultimate plan for getting rid of all the wires was the multiplexed control idea that had only three wires: POsitive, ground, and data. Back in the mid 90's that was supposed to be the solution. BUT it didn't work out that way, did it? Then along came the 42 volt idea, which was originally needed to power the electrically preheated catalytic converter. Fortunately for all of us that idea didn't succeed.
Presently most of those wires are already as thin as they can be mechanically and still have strength enough to survive building the car and driving it. The 36 volt-3 battery system would add more weight in the form of batterys than it would remove in the form of wires.
So the 36-42 volt system is just a bad idea, and it will continue to remain a bad idea.
rdelaplaza Higher voltages are fine in most other environments, but in a car the vibration does enter into the design of lamp filaments. Really, I read the report about the problems of the thinner filaments not being nearly as durable as the lower voltage lamps. Also, the controls for the higher voltage devices not used in cars are a fundamentaly different construction, and also in a much different cost area. So there really is no comparison between the electrical system in a car and any other area.
Besides all of that, the proposal of the higher voltage automotive electrical systems certainly looked to many like some company attempting to create a market for their product because nobody else was there yet, rather than because of any actual benefits.
Really, the bus arrangement with serial data to handle all controls would be the way to go, and it would be in place now if the bnefits outweighed the costs. BUT, just like going to the 42 volt system, the benefits do not outweigh the costs. The market has spoken.
Forget about lamp filaments; like the dinosaur, they are destined to extinction (pun intended), LED Solid State Lighting is here to stay, there are already LED light engines designed for industrial High Bay Lighting producing 25000 lumens that replace 450 Watts HID lamps, not bad considering that your car headlamps are around 60 watts ea.
Same applies to the Internal Combustion Engines; sooner than we expect electric vehicles will be a reality, when people and engineers realize the stupid idea invented and sold to us by BIG OIL and GREEDY car manufacturers, to STALL the develoment of the EV; that "the battery is attached for life to the vehicle, as unmovable part of the design".
Car manufacturers must stay doing what they do best, manufacturing cars, NOT BATTERIES, GREED is pushing them into their stupid schemes, they want to have the whole cake and eat it too.
Intelligent engineering in other countries like Israel and Germany, and some car makers like Renault are developing battery sizes, connector locations, control systems and capacity STANDARDS that ALL EV MANUFACTURERS CAN (and should) USE; to create a new breed of EV's with SWAPPABLE BATTERIES.
2 or 3 standard battery sizes, (like C, D & AA cells do), car batteries designed to be remanufactured swapping as few parts as possible, and reusing as many parts as possible, (even the basic replaced chemicals are recyclable) VERY IMPORTANT idea; the cost of remanufacture/replacement will be PRORATED in the cost per charge and subject to the laws of the market, like the price of gasoline, this approach will create thousands of jobs in the new industry of EV battery remanufacture.
Light EV's could use 1 to 3 small or med batt packs, trucks & cargo EV's could use up to 6 big size packs. Battery packs with tamper proof computerized energy tracking, battery condition and status dataloging to charge consumers only for the used energy; you already have one in your house energy meter.
Instead Gas Stations we will have charge/swap stations in every corner and the batteries can be charged at off peak hour rates to relieve the grid and equalize peak energy demands.
In terms of energy a short circuit protected power bus around the whole EV and a bidirectional optical fiber control bus (gigabyte) connected to every device in the vehicle. want to add reliability, (double that) and/or add token bus topology to the control signal, (in the circular control bus the control signals travel around in both directions even if the circle is broken in one point) use mass produced standard IC's for control bus access for the design of the std control modules; like brake, turning and marker lights, even the car audio could be pushed through the optic fiber and there will be an excess of capacity left for everything else.
Every different HP powertrain ratings will use it's own voltage, based in what is available in battery pack combinations, Accessory packs will standarize to reduce mass production costs, like Air conditioning systems sold as an accesory pack, Electric Power steering assisting, you name it.
So finally and sooner than anybody thinks the old schemes of vehicle voltages will die (as the 6 Volt battery did and the 12 V battery and filament light bulb will) and will be replaced by the new designs, new products and standards.
Only clunkers, rust shells, collectibles and vintage cars will still running on 6 and 12 volt lead and sulphuric acid flooded batteries.
There has been a major shift in your emphasis, from a discussion about the merits of a higher voltage system for cars with internal combustion engines to talking about electric vehicles. NONE of my comments were addressed to the choice of votages for electreic vehicles. EVs are a totally different area with no similarity.
As for LEDs being the only source of light on a car, probably a few years off that will happen, but most of us need to deal with the present until such a time arrives. And dealing with the present includes avoiding choices that would become obsolete in just a very short time. That would include creating a whole new area of 42 volt car parts that would need not only a lot of engineering to make them reliuable, but also a lot of manufacturing resources to make them at all.
Despite the very intense wishes of a lot of people, the passenger car as we presently know it is not going away very quickly. There are a lot of reasons for that that don't involve the auto companies or the oil companies, but rather the love of personal freedom that comes from personal mobility. IF I chose to do it, I could jump in my car and drive anyplace in the US, as long as I had money for gas, and I could do it in just a day or two. You simply can't do that in an EV, since you would need to stop and recharge every few hours, which, aside from slowing the trip a whole lot, provides "big brother" with a detailed trail of where you have gone. IN addition, those fast charges do take a toll on battery life, even on the most robust battery structures. In addition, the fast charge produces waste heat, which equates to wasted energy that is gone forever.
The concept of having batter-swap stations is about the stupidest idea ever proposed for anything associated with cars. The reason is that one would probably NEVER get a battery as good as the one traded off. We all know that is true, although a lot of folks will not admit to it. Look at the other areas where trading an empty tank for a full one exists and you will see exactly what I mean. As for "tamper proof" computerized energy monitoring and tracking, it is only tamper resistant until the hackers get in, usually within a month or so.
SO, If you really hate cars so much, I hope that you only use "green" public transport for all of your travels. I don't have time to waste going that slowly. AND, as I do not choose to be critical of those who choose such transport, I would expect a similar courtesy from those who elect to only utilize "green" public transport.
Raising the bus voltage to 42 VDC will reduce wire harness metal by 2/3 rds. Using more efficient devices will reduce the wire weight even more. Using LED lighting which is current mode rather than voltage mode will reduce the need for branch circuit protection shortening all of the wiring for lighting, again reducing wire weight.
I recently noticed that our express transit buses not only use LEDs for all marker lights, they now use them for headlights as well. If nothing else, this reduces the amount of service replacements (costs that a fleet manager is sensitive to) while increasing safety and fuel economy somewhat.
42V is dead and buried, 48V is the new future voltage.
The average car has ~1100 wires, ~¾ mile in length for now. With the increasing regulation & major reductions planned for CO2 things are going to get much worse as we lurch towards self-driving cars.
Extra sensors, cameras, computers & whatever else is needed to meet these new legal / techie requirements will result in pushing up the wire count & weight.
So we need the higher voltages & aluminium to reduce the wire weight given the much, much higher wire count otherwise we are back at square one. This will help by partially offsetting the weight increase caused by all the regulatory extras.
So for the average car 12/48 V systems with step down DC/DC converters will be the end result – 48V for high power & 12V for the legacy loads like car radios & sat-navs, etc.... Hybrids and electric cars already have a high voltage power source with step down DC/DC converters so there is less effort needed to up-tech them.
This doesn't count all the body changes towards a high strength steel bodyshell & lightweight alloys for the internal structure combined with plastics to replace glass windows.
Perhaps the future is a very high tech version of the old East German Trabant with modern materials replacing cheap steel & papier-mâché !!!
In reality a higher battery voltage will mean a larger alternator and a greater alternator load. The reason for the higher voltage is to provide enough electrical power for all of the loads. The higher voltage was never to reduce the weight of the wires. The first suggestion s for the 36 volt system, (42 volts) was to power the electrically heated catalytic converter. The concept was to delay the start while bringing the catalyst up to operating temperature using electrical heat. The power consumed was about the same as for cranking the engine for several minutes. The good news is that the idea was so very stupid that it was never released. What could be useful for the stop-start driving method would be a 24 volt alternator/starter unit, such as the Continental one pictured in the slideshow.
What stands in the way of the effective impplementation of the ultimate stop-start system is engine driven power steering, and air conditioning demands. Right now, I can shift my car into neutral and coast to a light, but it will not drop below 1500RPM until the vehicle is stopped. That is to assure power steering bost while still moving.
With most cars now being much lighter than when power steering first became popular, it seems that we should go back to the non-powered type of steering systems. They were not that hard to turn, and they were both less expensive and more reliable. And if we got rid of some drivers, so much the better. Fewer drivers, les crowded roads.
The military uses 28 volts on aircraft. I know because I spent most of my career designing automatic test tquipment for aircraft and missile electronics. I imagine the military uses 24 volts in vehicles. I have no experience with that.
I think the approach automakers are using is definitely supported by the need; i.e. looking at each component and improving that component's efficiency while evaluating what contribution can be made to reaching the CAFÉ standard. I don't really see how the standard can be achieved without significant improvement in technology and/or going to hybrid vehicles. With that being the case, the days of the shade tree mechanic are pretty much over. Growing up as a kid, my first lessons as a budding engineer came from working on cars. I suppose that will still be the case, but we could actually fix them back then. I'm not too sure a kid will be able to accomplish the same result with the new technology. In a way, this is sad evitable but sad.
I believe the future CAFE standards are more sophisticated, nuanced, and less draconian than appears at first look. The innovations discussed in the article will be refined, expanded, and integrated over time to become lower cost, more effective, and more widely applied. Not discussed were such possibilities as low friction coatings, further improvements in streamlining, lower friction piston rings, and the deSaxe offset cylinder technology which is already in use for some engines. Ceramic rollers can reduce mass and friction in roller tappets. The auto industry has yet to develop low cost, low mass, engine piston pins but they are conceptually feasible and many patents exist for various approaches. Still to come are merged computerized management systems to optimize driving efficiency. These would build on fuel economy techniques already used by so-called "hypermiler" drivers who seek maximum fuel efficiency, while avoiding the extremes of slow acceleration. Turbocharging and supercharging (exhaust gas and mechanical driven alternatives) have still further developments, aided by knowledge gained from the intense ongoing aircraft engine research programs. Low friction lubricants exist now and can be further optimized and developed. Body mass is being reduced with no ultimate limit yet in sight. Fully controlled valve movement will be refined and further adopted. The future CAFE standards can be met without destroying driving pleasure.
Looking at the picture of the air conditioning compressor it becomes clear that very early in the process automotive air cooling must be eliminated altogether. Not only does it not contribute anything towards moving the car down the road, but it also adds to the weight of the vehicle. In addition it does a whole lot toward encouraging folks to use their cars more than they really need to use them.
When will it be made part of the system that both the engine and the AC will shut off if the vehicle has not moved for... oh, say three minutes.
The idiots I see sitting outside the drive-in burger/ice cream joint in their nice AC'd Lexus with the windows up and the engine running... and the outside weather is delicious. And they're the ones who carp the loudest about fuel costs and pollution.
Of the various mechanisms presented, probably the one that is able to deliver the very most improvement for the very least effort is the combination alternator-starter shown in frame 4. Engine shutoff coupled with engine disengagement, all under driver control, or possibly driver plus computer control, could easily allow a doubling of the miles per gallon during city driving. It would not offer much improvement for constant speed driving, but in the case of suburban and urban driving, the ability to shut off and coast can provide a large reduction in fuel consumption. So why hasn't anybody else proposed such a system?
I see that one of the ideas from those brains at Delphi is to use aluminum as the conductor in wires. That will create a new aftermarket in replacement copper wiring harnesses in just a few months. The building industry learned the lesson many years back, and now aluminum wire is not very common in buildings any more. The automotive environment hyas most of the conditions that destroy aluminum wire rapidly, such as constant vibration and salty moisture. So we can be certain of a fairly rapid failure that will be a challenge to track and very hard to repair.
I would never even consider buying a car with aluminum wire, not even at half the price of a car that did not use it. Any automaker that tries to use aluminum conductors as a weight reduction tool will certainly need to greatly expand their warranty claims division to handle all of the claims.
I'm all for living as efficiently and environmentally congruent as possible, but all this effort and expense to reduce our production of pollution is completely negated by one moderately-sized volcano.
No, this is an elaborate sideshow to further weaken the little guy and usher us under the umbrella of totalitarianism when we - out of desparation - not only welcome but demand it.
TLuxon, sorry, but you are wrong to believe a volcano is more significant than human pollution. That is because although a volcano will produce more CO2, it also produces raw minerals that absorb more CO2 than they produce. Then when you also consider the particulate cooling, they counteract global warming, not add to it. In fact, one of the proposed solutions to global warming is to deliberately cause more volcanoes.
I'm not so sure that's wrong. Human driven CO2 is also accompanied by minerals that absorb it, and plant life requires CO2 regardless of origin. So little is agreed upon as to the net benefit or liability of or even what constitutes 'excessive' levels of CO2, that it borders on economically insane to throw so much money at this 'problem' without better understanding more of the factors and ramifications of such measures. For example, I don't believe we're applying nearly enough attention to the corresponding - coincidental or not - depletion of oxygen levels, which we and all animal life are dependent on.
I'd much prefer to see the scientific community push back more against the players who have jumped to premature conclusions in order to drive their agenda of global control and ownership of the populace of the planet. I don't know how they got away with minimizing the factors of the Sun and natural climate cycles for so long, but that has greatly skewed 'the science'. So few seem to give consideration to the very real possibility that CO2 increases were DRIVEN by warming rather than driving it. As complex as their modeling was, it didn't come close to replicating the complexity of the organism itself.
Many fundamental principles of science have been violated during all the 'debate', especially evident in the scorn and demonization of dissenting opinion. Dissent must be dealt with in a respectful manner by all sides or credibility will always be in question.
There used to be minerals from human CO2 sources that mitigated, but not after catalytic converters. Now car exhaust is "bright" pollution that causes much more global warming than the smog of the past did.
There is no one making money off promoting global warming, and there is no major cost associated with minimizing it, because the main goal is conservation, and by saving oil, that saves money.
The scientific community has explored past climate change cycles, and we are supposed to be already into the part of the cycle that is getting colder, not warmer. We have tracked solar output, and know that is not the cause.
But I agree that the reduction of O2 is a significant problem that should be getting more attention.
Wouldn't you like to rephrase your statement: "There is no one making money off promoting global warming, and there is no major cost associated with minimizing it, because the main goal is conservation, and by saving oil, that saves money."?
You don't seriously believe that striving for 54.5 MPG isn't costing far more than the amount of oil/money it's going to save, do you? Perhaps you are aware of some manufacturers who'll back you up on that?
The average driver spends about $2000 a year on gasoline, so doubling milege saves over $1000 a year. It does not cost more than a couple thousand to make a car light enough to get 54.5 mpg. I had a Fiat 850 in the 1960s that got 40 mpg back then, and it was fun to drive. I had an MG 1100 back then that got 35 mpg and was fun to drive. I drove a Nash Metropolitan that got 35 mpg back then, and was fun to drive. It is not that hard to get getter mileage than we do. I can buy a VW Polo that gets 70 mpg right now in Europe, and it costs only $14k. Europe has stricter emission standards than we do.
I see where you're coming from. My second car was a 1974 Mercury Capri (German made) and it was relatively heavy compared to what could be done now. I loved driving it and got 35 mpg on the highway.
Among the challenges we have today that we didn't have 40 years ago are the numerous regulations and standards that each in their own way have negatively impacted fuel efficiency. I don't believe it's going to be a trivial matter either financially or technologically to make a car that is safe and comfortable for my family of 4 that gets 54.5 mpg and has a reasonable cost of ownership.
Despite the tone of my comments, I personally believe we've made glutonous and greedy use of combustible fuels, and I want to be efficient and judicial in my use of them. My contention is solely with the motivations behind much of the controversy over how reductions should be made. I guess I've seen too many 'remedies' that are worse than the 'disease'.
For example, I don't think explosive airbags are safe, and just add weight and cost. I think heavy catalytic converters turn soot into much more toxic cyanates, formalins, sulfites, etc., they don't test for. In the US it is very hard to even sell a diesel at all.
Right. If the unsuspecting public were to follow the money, they would come to see that many millionaires have been made from the creation of almost every regulation. There's always a 'solution' that seems ready-made for the 'problem', and most of the time the resultant remedial regulation requires that solution.
Upon that realization, it forces one to question everything that's touted to be for our good.
Tluxon, you are exactly correct about how much money some are making from the hysteria about alleged global warming. Of course I also agfree that we should strive to reduce toxic pollution as much as we can. But I also am quite concerned about those who are using this scare to advance their personalmagendas and take away many of our freedoms, since, aside from that, they are also failing to consider the unintended consequences of many of their "more severe" actions. Unthinking actions can lead to far worse outcomes.
OK, VW group to off-set their car consumption bought Ducati, so now when A(nother) U(n) D(oubted) I(diot) driver hits a Ducati rider they get both repairs too.
All cynicism aside a lot of car makers also have a bike division, or in the case of BMW the other way round, so not everyone is trying so hard yet. That said we drove 690 miles over 6 days recently in a 2008 Suzuki (badged Vauxhaul Agila) Splash 1.3 CDTi. Thats the Fiat 1.3 common rail turbo intercooled diesel, without air-con it returned at ~65 mph 71 MPG, with air-con, and several hours of city centre crawling, overall 4 up with luggage it returned 65 MPG. And whilst we're Europeans, we're not small built people either!
The Splash/Agila is still being built, but Suzuki/GM stopped buying in the Fiat engine in 2010, that was a mistake, neither of the petrol engines can return such good fuel economy with useable power, perhaps thats where the real future lies, more collaboration, less competition?
Referring to slide #7, aluminum wiring. That's a very bad idea. While aluminum may be lighter than copper, aluminum oxidizes far more easily than copper, causing faulty electrical connections. It was used in houses for a while, but caused many fires and has since been discontinued. Now add to that, the temperature and humidity of an automotive application, I predict that the reliability will be extremely low. Bad idea!
An even "better" idea for lightweight wiring is Sodium. High conductivity, light weight. Amazingly, it is trying to make a comeback (www.sodiumwire.com). Just remember, don't let it get wet, and never, ever, feed it after midnight.
A big problem with a high battery voltage like 36 or 42 volts is that the various incandescent lamps in the vehicle will have longer, thinner, more fragile filaments. This would greatly reduce their reliability. While everything is moving toward LEDs, switch-mode power converters will be needed to adapt LEDs to such a high voltage. This would cause weight, cost and reliability issues. Of course, even at 12 volts, higher powered LEDs would require switch-mode power converters to avoid energy loss. The size and cost of the components in a switch-mode power converter are affected by the wattage, not the battery voltage.
Tesla Motors’ $35,000, 200-mile electric car may not revolutionize the auto industry by itself, but it could serve as a starting point for a long, steady climb to a day when half of the world’s vehicles will be plug-ins.
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