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Diesel-Like Engine Could Boost Fuel Economy By 50%
bonch writes "Autoparts manufacturer Delphi has developed a diesel-like ignition engine running on gasoline, providing a potential 50 percent efficiency improvement over existing gas-powered engines. Engineers have long sought to run diesel-like engines on gasoline for its higher efficiency and low emissions. Delphi's engine, using a technique called gasoline-direct-injection compression ignition, could rival the performance of hybrid automobiles at a cheaper cost."
WOOHOOO!!!
I don't really care about the karma here, but there's been so much bad news lately this is rather refreshing.
I'll let the critics speak and explain why this is not as good as it sounds, but FTS it's inspiring.
None of us know everything. Therefore we're all naïve.
From what I understand, the major challenge of combustion without a spark plug for gasoline is preignition. High pressure direct injection allows normal spark-plug motors to run at higher compression ratios with lower chance of knock (preignition), so that was part of it, but I wonder what other fabulous tech was used to get this to be feasibly production ready. Very cool.
People will just drive more to make up for the greater efficiency, and still whine about gas prices...
Can't wait to have my self-driving electric flying car by 2032.
I mean everything is moving over the next two decades to electric anyway.
Electric has a moving target to hit, just as it has for the last 100+ years. Batteries are not the only technology that can improve in the next two decades.
W..w..W - Willy Waterloo washes Warren Wiggins who is washing Waldo Woo.
What keeps diesel engines from becoming a standard in the US? I know regulations nearly disappeared them from the market, but that was for environmental reasons, which are the very reasons why diesel cars are attractive. While in Europe it is not outside the norm, here it seems like you are committing a crime if you run a diesel engine.
Also - since diesel engines are so efficient and all - what stops them from making a hybrid car that benefits from the even greater efficiency of diesel? or this new type of diesel like gas engine for that matter?
Seems a bit redundant really, I mean everything is moving over the next two decades to electric anyway.
Perhaps. It will depend on if we can figure out how to store electricity in the car less expensively then we can store the equivalent energy in a liquid fuel tank.
OK, yes, this makes a gasoline engine more efficient by emulating a diesel. Why not just go with diesel, then?
Is there more energy density in gasoline? Is it cheaper to produce? Or is this just about gasoline being more widely available and consumers being more comfortable with it?
I'm asking. Someone here knows, I bet.
It's probably inevitable-- it's just a question of when. Battery cost per kWh has been decreasing at around 10% per year, and gasoline is getting consistently more expensive. It seems incredibly unlikely that both of these would stop moving toward the crossover point.
Seems a bit redundant really, I mean everything is moving over the next two decades to electric anyway.
Until we see new power plants being built I am not so sure we will have a large scale transition to electrically powered vehicles. Various parts of our electrical grid are already pretty stressed out and seeing periodic brown outs and black outs. This could put a damper on large scale adoption of electric vehicles.
At least they won't rival the hybrid version of this engine.
Knowledge is how to play a game, intelligence is how to win, wisdom is knowing what game to play.
Don't forget that, when considering the extra mining and transportation of rare earth metals required to build a hybrid car, its overall environmental impact might not be any better than a conventional gasoline engine. My choice would be to buy a gasoline powered car with 50% improved efficiency over hybrid--at least until battery technology (and China's environmental policies!) improve.
The key distinction, as I'm aware, between diesel and gasoline is all about the ignition to begin with. In a gas engine, you create a spark to ignite a carefully mixed gas/air vapor. In a diesel, you don't need the spark, instead using sheer pressure from a much higher compression ratio. (this also leads to higher power per stroke, and therefore greater theoretical efficiency) Presumably they've found some way to reliably ignite gasoline without said spark, thus reaping the same compression ratio benefits or some such thing, I would guess.
Check out this link on HCCI, which this sounds like it's based on...
http://en.wikipedia.org/wiki/Homogeneous_charge_compression_ignition
Basically, emissions from Gasoline are more easily cleaned up than Diesel, but the need for spark ignition hurts its efficiency over traditional Diesel engines and the lower compression of traditional gassoline engines means that they extract less energy from the combustion of gasoline (as a percentage of total energy content) than diesel engines do from Diesel fuel. This has the potential to be more efficient than a gasoline direct injection atkinson cycle gasoline engine of similar power output specification and, if it retains the gasoline engine's preferred characteristics for usage in road going small hybrids, will non-trivially imporve the efficiency of Hybrid vehicles as well as regular gasoline only vehicles.
You keep using that word "justice." I do not think it means what you think it means.
If by "economic social justice" you mean "ways I believe that I should spend your money" and if by "unjust" you mean "bad because it is not how I would allocate your resources," then maybe.
But "justice" is the application of law to achieve a fair, reasonable, and consistent outcome. If your neighbor gets fined $100 for leaving trash on the street and you do the same thing but don't get fined, that's unjust.
Enabling or subsidizing somebody else to have access to something that they do not currently have may be altruistic or philanthropic and it may even be a good idea, but it's got nothing to do with justice. "Social Justice" might have meant something once, but it's been hijacked in pursuit of so many agendas (because everybody likes Justice, right?!?) that it's about as meaningful as the names of laws, where you regularly see things like "The American Equal Opportunity And High Paying Jobs For Everyone Act" that does nothing like what the title says.
Efficiency of gasoline is better than oil in the same conditions. But diesel engines have much higher compression ratios (needed to burn the oil and give the self combustion). The problem with gasoline is/was that you could not get those compression ratios until now without explosion or engine melt. :)
Sorry for the simplification
I gave up with the idea of an useful sig...
Gasoline. Because we still have glaciers.
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This. Personally I can see all-electric cars being even more capable than fossil fuel cars, at a lower cost, and cheaper to run, over the coming twenty years.
Hybrid will use this as well.
It's good thing, hope it pans out.
The Kruger Dunning explains most post on
I don't think it's much of a moving target ... electric needs to reach a 600 mile range and charge in 10 minutes. That will make it an effective transportation alternative for all current automotive travel. It really doesn't need to get any better than that.
It's hard to see how electric can be beat in the long run. Even a 50% decrease in fuel use won't make gasoline fueling the cheaper choice.
"Who is the Journal of Quantum Physics going to believe?" --Stephen Hawking
It's probably inevitable-- it's just a question of when. Battery cost per kWh has been decreasing at around 10% per year, and gasoline is getting consistently more expensive. It seems incredibly unlikely that both of these would stop moving toward the crossover point.
Gasoline engines have been keeping up with that 10% though. In 1998 the Ford Mustang GT with a 4.6L V8 had about 215hp. In 2011 the Mustang GT 5.0L V8 packed in 412hp. That's about 7% a year increase in power and a slight increase in mileage. It stands to reason if that extra efficiency was put towards more mpg instead of more power, that crossover point could be farther out than you think.
The good news is it's getting better on both fronts and fast!
No I don't see all electric in 20 years.
Unless we solve the problems of...
1. Range
2. Recharge Time
3. Getting the Grid to handle all the cars.
4. How do we generate all that electricity to do so.
Range and Recharge time. is the biggest issue for me. I travel 30 miles to work and 30 miles back. That is 60 miles. Most electric cars are pushing 100 miles, but that is the ideal range... what is the range going up a mountain? What if the batteries after 8 years are not optimal...
Next my parents live 800 miles away. Say I have an electric car that can do 500 miles per run. I drive mostly there, however I need to recharge. Can I recharge in 5-10 minutes or will I need to spend the night charging my car.
I do not have the money for a car to drive to work and a car to drive longer ranges.
So we will still need chemical powered cars, until these issues are fixed. I am happy to see that they are getting a lot more fuel efficient. That is a good sign, because electric cars are not going to solve all the problems.
If something is so important that you feel the need to post it on the internet... It probably isn't that important.
long distances like the beach
If you're a long distance from a beach, you're doing it wrong.
I've seen people use the term "This." just as you used it here.
I am not sure what "this" means.
Is this some kind of new shortcut phrasing? What does it mean?
I am a native English speaker (but an old person now and trying to keep up to date).
I don't read your sig. Why are you reading mine?
This is nothing new really. They had similar technology back in the 70's but it was never pursued much because people preferred driving BIG GAS HOGS. 1975 Honda Civic had a similar type of technology - http://en.wikipedia.org/wiki/CVCC. I owned one of these cars. It was small, an automatic without the D (drive), just speeds 1 and 2. Wish I still had the car today.
-- By all means let's be open-minded, but not so open-minded that our brains drop out.
It means "I approve of the above message which neatly encapsulates most of my feelings on the matter".
If you work out the math of various combustion-work cycles (see Otto Cycle, Diesel Cycle), and then take a look at how they are implemented in a typical gasoline or diesel engine, one of the things you immediately find is that efficiency is directly proportional to compression ratio. That is, the more you compress the air (or air-fuel mixture) before igniting the fuel, the better your efficiency.
Gasoline engines tend to be limited in their compression ratios, because if you compress the air-fuel mixture too much, it'll spontaneously ignite while the piston is on the upstroke, a phenomenon called pre-ignition or engine knock (because of how it sounds, I suppose). Diesel fuel burns a bit differently than gasoline, and diesel engines take advantage of spontaneous ignition: they purposefully have high compression ratios to heat up air in the cylinder, then inject the fuel when the piston is at/near the top of its stroke, where it immediately ignites. But diesel, as a fuel, has some practical downsides which has limited its more widespread adoption, primarily how cleanly it burns.
If, on the other hand, you could produce an gasoline engine that uses diesel-like compression ratios, and inject the gasoline at maximum compression, as a diesel engine does, you could have the best of both world: greater efficiency due to high compression ratio, cleaner running due to burning gasoline. But such an engine, for various technical reasons, has historically been difficult to achieve. Maybe these guys are really on to something.
I don't think it's much of a moving target ... electric needs to reach a 600 mile range and charge in 10 minutes. That will make it an effective transportation alternative for all current automotive travel. It really doesn't need to get any better than that.
It's hard to see how electric can be beat in the long run. Even a 50% decrease in fuel use won't make gasoline fueling the cheaper choice.
How much will it cost to purchase the electricity to recharge that battery pack? It is naive to assume that electricity to recharge cars will be cheaper than gasoline to power cars once the electricity is the primary fuel source. Gasoline is not priced by supply and demand, it is priced by what the market will bear. Why would you expect electric recharging to be any different?
No. It's cheaper to own then rent. Not just for cars but virtually everything.
My AC stalker: " I personally agree with your posts most of the time, but that won't keep me from modding you troll"
Meh. I'm waiting for my teleporter. There's no way I'd want to step outside with everyone flying badly maintained autonomous electric cars.
However, putting this in a Hybrid would provide the better of both worlds in the near term.
Hydrogen is the exact same story, actually. Somebody has to produce the hydrogen for your fuel cells, that takes energy.
We hope your rules and wisdom choke you / Now we are one in everlasting peace
1. is slowly being fixed by better batteries.
2. Charge times at a station can be down to 10 minutes already
3. Smart grid handles this.
4. not really needed since we have so much off peak power
5. If you parents are that far away consider taking a plane.
Can you make gasoline in your garage from sources that fall on your property regularly?
If by "economic social justice" you mean "ways I believe that I should spend your money" and if by "unjust" you mean "bad because it is not how I would allocate your resources," then maybe.
Straw man. In the context of environmental protection, "justice" would mean things that the air people in poor neighborhoods would be nearly as clean as the air people in wealthy suburbs breathe.
I'll give you another example. Some years ago there was a proposal to establish airline service at an air force base which for decades has been a research center that hasn't supported combat aircraft since the 50s. I remember walking into the break room at work and hearing two people who happened to live in a very affluent (median income $160K) suburb near the proposed airport talking about what a terrible idea it was, because of all the noise it would bring to their quiet neighborhoods. Having grown up in a poor urban neighborhood, I had to smirk. Airliners flew over us all the time. The very poorest people lived right smack next to the airport, and they almost never flew. *Not* establishing a second airport meant that as those suburban folks flew more and more, the number of flights coming in over *us* went up.
Now the world is full of inequalities, and some of them are just, but not *all* of them. It is a good thing to keep a quiet, bucolic suburb pristine, but is it right to do that at the expense of making somebody else's neighborhood worse? Rich people don't deserve peace and quiet *more* than poor people do. And if you stop an airport in your backyard, you should at least have the decency to support noise regulation for people who don't have the political power to stop airlines from routing more flights over their neighborhoods. I'd call at least attempting to reduce the impact of services on people who can't afford to use them progress toward "economic social justice".
Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
GDI is nothing new, but it didn't become viable until recently.
Ford calls their turbocharged GDI engines EcoBoost - I was shocked at the mileage I got from a rental Ford Edge with one of these in it. Good mileage from a fairly large vehicle that also had great acceleration.
Mazda calls it Skyactiv (Probably fairly similar to EcoBoost due to the historical close relationship between Ford and Mazda)
Hyundai doesn't apply any fancy marketing terms for it, but they have had GDI engines in their non-turbo (and maybe the turbo too) Sonatas for 2-3 years now. 6-speed + GDI engine = car that hauls serious ass while still getting great mileage (Along with the Edge, the Sonata was one of the best rentals I've had in the past few years.)
retrorocket.o not found, launch anyway?
Re: "Gasoline is not priced by supply and demand, it is priced by what the market will bear."
Ah. Controlled by the Trilateral Commission, no doubt. Or perhaps the Illuminati.
TANSTAAFL
No I don't see all electric in 20 years.
Unless we solve the problems of...
1. Range
2. Recharge Time
3. Getting the Grid to handle all the cars.
4. How do we generate all that electricity to do so.
1. Range is increasing with every generation, and is already sufficient for 90% of daily needs.
2. Recharge time is also improving steadily, and is more a matter of infrastructure for convenience than time required. Recharge overnight at home, recharge during the day at the office, recharge while shopping, etc.
3 & 4. No clue - but I assume there are engineers working on solutions. Let them.
Range and Recharge time. is the biggest issue for me. I travel 30 miles to work and 30 miles back. That is 60 miles.
Charge at home overnight, charge at the office, you should have a mostly full charge when beginning either leg of your commute.
Most electric cars are pushing 100 miles, but that is the ideal range... what is the range going up a mountain?
Range will be effected by terrain -it is no matter your fuel source.
What if the batteries after 8 years are not optimal...
Batteries need to be replaced when they get old, oil needs to be changed, tires need to be replaced... its a fact: maintenance needs to be done.
Next my parents live 800 miles away. Say I have an electric car that can do 500 miles per run. I drive mostly there, however I need to recharge. Can I recharge in 5-10 minutes or will I need to spend the night charging my car. I do not have the money for a car to drive to work and a car to drive longer ranges. So we will still need chemical powered cars, until these issues are fixed. I am happy to see that they are getting a lot more fuel efficient.
The answer to these concerns is to rent a car for longer trips. I see Hertz has rental cars as low as $14 /day for some sort of econobox. I think my last multi-state driving vacation was about $150 for a week in a mercedes c240 (thanks to a free upgrade coupon).
That is a good sign, because electric cars are not going to solve all the problems.
Electric cars or hybrids do not have to be perfect. They need to be good enough for daily use - we use diesel rigs (18 wheelers) for hauling big loads, and dont say that because a honda civic cant haul the same load every day it isnt a viable commuter car. Different solutions for different problems.
"You want to know how to help your kids? Leave them the fuck alone." -George Carlin
No, but I can make alcohol from sources that grow on my property...
An enigma, wrapped in a riddle, shrouded in bacon and cheese
Word.
<xml><I><am><so><damn>Web 2.0</damn></so></am></I></xml>
When you get kids and a wife, you'll probably (not certainly, but probably) wind up owning two cars. I have a Camry and a minivan - I would gladly trade the Camry in on an electric car if my payback period were not infinite. I'd still have the minivan for longer trips.
Indeed you can't beat the price of a car for trips when you have multiple passengers. Well, maybe the bus.... Last time I looked it was still only about $12 to take the bus from Philly to NYC, which is hard to beat.
As an aside, we have a fundamental problem with our nation's infrastructure when it costs less to drive my own car into a major city than it costs to take transit of some form. Even given the atrocious parking fees, tolls, wear-and-tear, and gas, it will be cheaper for me to make the 6-hour trip up to Boston with my family of four by car than by Amtrak. Amazing.
W..w..W - Willy Waterloo washes Warren Wiggins who is washing Waldo Woo.
Really, it depends. If you live and work in a large city center and only need the car occasionally to run an errand or go on a weekend trip, but end up paying $300 a month to park in a garage in addition to an auto loan and insurance, then taxis, zip cars, and rentals may be far cheaper.
but it isn't getting better mileage. It is easy to design to maximize horsepower. The difficult part is maximizing mpg while maintaining acceptable performance.
It's about an 8% increase in fuel economy, which is pretty good, but downright impressive with almost twice the power. It's pretty disingenuous to imply that all they did was crank out more power. It's also not really a reasonable comparison to say 26 MPG "sucks" compared to a subcompact economy car, because it's phenomenal for a 400+ HP sports car.
It's not naive at all, it's simple physics, which apparently you know absolutely nothing about.
Most of the energy in gasoline is used to create heat, which is simply wasted. There's no way gasoline engines can even come close to electric cars in efficiency, once the battery problem is solved. Of course, a lot of electricity is still created with thermal cycle technology like cars (coal, oil, natural gas-fired plants), but a lot isn't (nuclear, hydro, wind, and solar). However, the efficiency of any power plant is far, far more than any small gasoline engine can ever hope to be, due to economies of scale and the lack of need to operate at highly variable speeds.
don't believe me, check out the VW sites where drivers are posting their own experiences and do 46mpg or better on a regular basis.
Indeed - just bought a 2012 Jetta TDI for my wife, as she has a 60-mile-each-way daily commute down the interstate:
Average mileage: 50mpg... and she can often fill up on diesel for less than what I pay for the same amount of gasoline if she goes to Sam's Club.
An enigma, wrapped in a riddle, shrouded in bacon and cheese
Lucky you! I used to live next to the company that I work at, so I walked into work. Then I got married and had kids. Now instead of "where's the closest apartment complex to work" I had to optimize based on school systems and distance to both my work and my wife's. I think we did pretty well - I have a 10-mile commute and she has a 5-mile commute... not quite splitting the difference distance wise, but time-wise my commute is actually better because about half of mine is highway. I can't bike without taking my life into my hands. Neither can she, since she drives through an absolutely horrible part of the city.
So for us, an electric car would be perfect, but they can take their time... at less than 5000 miles/year, that Camry will last a looooong time.
W..w..W - Willy Waterloo washes Warren Wiggins who is washing Waldo Woo.
Apples to apples
Battery efficiency 95%
Power generation efficiency 50-70%
Electric transmission efficiency 80-98%
Assuming best case, net efficiency 0.98 * 0.95 * 0.7 * 0.98 or about 64% for an electric car.
"Gasoline is not priced by supply and demand, it is priced by what the market will bear."
Isn't that the same?
No. Supply and demand has some kind of curve for both, and and equilibrium is reached between the two. Since the demand for gas is so inelastic, instead of an X supply and demand curve, it is closer to a sideways t. As such, gas companies can pretty much charge what they want. The reason they don't is because of public backlash (which translates into government oversight, which they don't want), not because of as prices go up, people buy less gas and prices drop. In reality, as the price of gas goes up, people buy less of everything else, but the overall demand for gas changes very little. Put differently, what the market will bear manifests doesn't mean it manifests itself by lower demand.