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SKYACTIV-X: first commercial gasoline engine to use compression ignition

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Re: SKYACTIV-X: first commercial gasoline engine to use compression ignition

#161

Post by coredog64 »

jonsen wrote: post #94
ChuckMcM wrote: post #18

A reuters story on how it works: https://www.reuters.com/article/us-mazda-strategy-idUSKBN1AO... So this is 'gasoline' diesel. Or diesel without the NOx. Which, in theory, would give better fuel economy and possibly better torque. And it will ship in cars in the 2019 model year (so possibly as early as late next year). To me, it sounds like a "Don't pass"[1] bet on electric cars. Which they also are working with Toyo…

Someday someone might invent an efficient process for making gasoline from renewable energi sources.

LANL published a paper circa 2007 or 2008 on how to make carbon-neutral hdyrocarbon fuel using carbon in the air and the electricity and waste heat from a nuclear plant. According to the paper, it was competitive with oil-based gasoline at around $5/gallon.

Re: SKYACTIV-X: first commercial gasoline engine to use compression ignition

#162

Post by raman325 »

mywittyname wrote: post #127
Danihan wrote: post #3

>Compression ignition and a supercharger fitted to improve fuel economy together deliver unprecedented engine response and increase torque 10-30 percent over the current SKYACTIV-G gasoline engine.*3 Wow. I already have a 2016 Mazda 3 that gets around 40MPG (even though it's not a hybrid) and it's already pretty peppy. Probably the best car I've owned, and I've owned several nice sports sedans. Getting 40MPG is too c…

> Blows any hybrid out of the water for total COO. Not so sure about this. I have a 2014 3i GT and my wife has a 2014 Prius. Hers was cheaper to buy, gets way better mileage (29 v. 44) and needs less frequent oil changes (which are free), and is worth about $1200 more now. It's a little faster, nicer inside, and much more fun to drive. But cheaper, nah.

I'd assume the parent comment is referring to the base package version of the Mazda 3. I was able to get a 2015 Mazda3 S Touring for ~$25k with all taxes and fees included, so I think $20k is a fair estimate if you assume the base package

Re: SKYACTIV-X: first commercial gasoline engine to use compression ignition

#163

Post by madengr »

fnj wrote: post #104
kbenson wrote: post #86

Earlier quoted context omitted.

> Pure EV purists dislike PHEVs because they have the complexity of an ICE car + an EV car, but I think there's some serious advantages. I would imagine most the complaints are for when the ICE actually powers a drivetrain. If it's essentially a generator to keep the batteries from depleting too far, that's not much extra complexity it all. Have a problem with the generator? Just swap it out with a new or rebuilt one…

> a Tesla uses about 300 Watts a mile @ 55 Mph This is nonsense. The dimensions are wrong. Watts are instantaneous power. To be meaningful, you would have to give either kWh/h or kWh per mile or km. Besides that 300 W is only 0.4 hp. Sorry, but that is just not credible.

Just for reference, I average about 4.5 mile/kWh in my Leaf.

Re: SKYACTIV-X: first commercial gasoline engine to use compression ignition

#164

Post by 33W »

SeanLuke wrote: post #160
33W wrote: post #92

Earlier quoted context omitted.

They also have an interesting somewhat-hybrid called i-eloop that uses regenerative braking and a capacitor to power auxiliary systems: http://www.mazda.com/en/innovation/technology/env/i-eloop/

I considered i-eloop when it came out for its first generation, in the 2014 Mazda 3. It was estimated to bump my city MPG by 1 . And was only available in a very expensive package. I passed.

I have a '16 Mazda 3 without. I agree that it is non-economical, but interesting.

I'd like to have it with a larger lithium-ion that can remote start only my AC for a few minutes while I walk to the car in the summer.

Re: SKYACTIV-X: first commercial gasoline engine to use compression ignition

#165

Post by calafrax »

robin_reala wrote: post #49
oatmealsnap wrote: post #35

Earlier quoted context omitted.

Gasoline engines aren't going away for a while; even when every self-driving car is electric, there will be a market for people who want gasoline engines. If it gives a bump in fuel economy to the next (last?) generation of gasoline and hybrid vehicles, great! I also wonder if the maintainability of these engines will be the same as with diesel. That would be another big benefit.

Outside of Europe maybe. Inside, well, UK and France have already said no more ICE vehicles to be sold past 2040, and other countries are planning the similar (including India). That’s a big loss of market and consequent economy of scale.

2040 is a long way away. very easy to pass laws that take effect after you retire. and very easy to change them after you retire as well.

Re: SKYACTIV-X: first commercial gasoline engine to use compression ignition

#166

Post by CyberDildonics »

linksnapzz wrote: post #143
robin_reala wrote: post #49

Earlier quoted context omitted.

Outside of Europe maybe. Inside, well, UK and France have already said no more ICE vehicles to be sold past 2040, and other countries are planning the similar (including India). That’s a big loss of market and consequent economy of scale.

In the 1990s, the CA state gov. wanted 10% of the cars on the road to be EVs by 2000. Wow, was that ever effective.

That's interesting, do you have a link to the law they passed?

Re: SKYACTIV-X: first commercial gasoline engine to use compression ignition

#167

Post by calibration263 »

pkulak wrote: post #148
ouid wrote: post #140

Earlier quoted context omitted.

I visited a Tesla store once in mountain view, and they have a great little demo where you can check the cost of charging your car in various states. Washington DC, for whatever reason, gets its electricity from a gasoline power plant. In Washington, the Model S gets 28 MPG. This happened a while ago so I could be misremembering, but regardless I don't believe that the environmental value of electric vehicles has bee…

https://en.wikipedia.org/wiki/The_long_tailpipe#Criticism The biggest nail in the coffin of the long tailpipe fallacy is that you can drive an EV farther on the power needed to refine a gallon of gas than you can drive a ICE car on that same gallon. So, even if you built a gasoline engine that had absolutely no emissions, and oil bubbled up into crude lakes right next to every refinery, EVs would still be more effici…

Your article states 87.7% efficiency in gasoline refining.

Energy density of gasoline is 34.2 MJ/L: https://en.wikipedia.org/wiki/Energy_density

This means there was 4.8 MJ of energy spent to create 1L of gasoline. The 70kWh(250MJ) tesla is reported to have 390KM range. 4.8 MJ would be 1.92% of the range, or about 7.5km. The Mazda 3 has a combined fuel economy rating of 33 MPG, which is about 14KPL.

As far s I can tell, your statement that an EV can go further on the power needed to refine a gallon of gas, than an ICE car can drive is off by a factor of almost two.

That said, arguing an electric car can go a certain distance based on inefficiencies of another unrelated process is not a very meaningful argument. You need to look at the efficiencies and CO2 produced for drilling/transporting/refining/burning gas vs producing/transmitting/storing/using electric power, and probably the costs of dealing with peak loads vs non-peak loads, and even then the argument is heavily weighted on where your power comes from.

Re: SKYACTIV-X: first commercial gasoline engine to use compression ignition

#168

Post by calafrax »

twblalock wrote: post #98
stirkac wrote: post #2

Mazda is one of those companies just don't stop revolutionizing. First they got rotary to be actually usable. Now this.

Compression ignition is more an evolution than a revolution -- it's an iterative improvement on an existing technology. Skyactiv exists in the first place because Mazda does not have the money or engineering resources to build a hybrid or electric car by themselves. I suspect that in a decade or two, Mazda's decision not to start building hybrids and electric cars when the other major brands were doing so will be reg…

investing in high efficiency gasoline engines is a much better bet. the world will be running on gasoline for decades at least. even if europe (doubtful) or US (very doubtful) pull out of gasoline there will still be billions of potential customers around the world.

Re: SKYACTIV-X: first commercial gasoline engine to use compression ignition

#169

Post by linksnapzz »

IgorPartola wrote: post #128
linksnapzz wrote: post #34

Earlier quoted context omitted.

Chrysler made several generations of turbine cars in the '60s. http://www.allpar.com/mopar/turbine.html It was not, in the end, a production car, but there was a lot of data gathered as to performance and reliability in real-world settings. Not too long ago, Jaguar had a concept CX-75, which was a hybrid mid-engined supercar where the piston engine was replaced with two Bladon Jets micro gas turbines. After 2008, the…

Damn. That sounds like they almost made it work. I wonder how those cars would have done with corn ethanol. Electric boost for initial acceleration and better heat exchangers would have probably completely eliminated the remaining problems with them. Thanks for the link!

Dunno about corn ethanol, but agave worked: http://www.roadandtrack.com/car-culture/a33239/that-time-the...

Re: SKYACTIV-X: first commercial gasoline engine to use compression ignition

#170

Post by [deleted] »

timerol wrote: post #105
kbenson wrote: post #86

Earlier quoted context omitted.

> Pure EV purists dislike PHEVs because they have the complexity of an ICE car + an EV car, but I think there's some serious advantages. I would imagine most the complaints are for when the ICE actually powers a drivetrain. If it's essentially a generator to keep the batteries from depleting too far, that's not much extra complexity it all. Have a problem with the generator? Just swap it out with a new or rebuilt one…

The units in the linked thread are slightly wrong, which was corrected later in the thread. 300 Wh/mi * 55 mph = 16.5 kW. The most powerful generator I see on Honda's site is 10 kW for $5400.

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