Cleaner than electric? Mazda talks up gasoline engine fuel economy ambitions for SkyActiv 2

Mazda talks up engine fuel economy ambitions for SkyActiv 2
( —Auto-focused sites are buzzing over a recent report in Autocar, reporting Japanese automobile manufacturer Mazda's future gasoline engine technology, which will reduce carbon dioxide emissions below the amount generated to power electric cars.

As noted, while do not pump out CO2 as they travel, they have a carbon footprint created when the electric power they run on is produced. Though not due for some years to come, the very idea of a gasoline engine efficient enough to release less carbon dioxide than an electric car was tantalizing enough to make the numerous blog and car site headlines. Specifically, the spotlight is on advances in Mazda's SkyActiv engine technology. Mark Tisshaw, writing in Autocar, said "So efficient is its latest internal combustion engine technology, the Japanese firm claims that it could even eclipse pure electric cars for well-to-wheel CO2 emissions, without adding expensive and heavy hybrid or plug-in hybrid components."

At Mazda, the engine of the future is called the SkyActiv-G Generation 2, a follow-up to Mazda's SkyActiv-G Generation 1. For SkyActiv-G Generation 2, Mazda will adopt homogeneous charge compression ignition (HCCI) and an even higher compression ratio of 18:1 over SkyActiv-G Generation 1 high compression ratio of 14:1. Mazda said on its site that increasing the compression ratio considerably improves thermal efficiency. According to Autocar, it is likely SkyActiv-G Generation 2 technology could arrive in production before the decade is out..

For SkyActiv-G Generation 2, Mazda will adopt homogeneous charge compression ignition (HCCI) and the higher compression ratio of 18:1. Autocar said The HCCI system works in a way similar to a diesel engine, using piston compression rather than a spark plug to ignite the mixture in the chamber.

Automotive News explained how HCCI "compresses the fuel-air mixture to such a high pressure and temperature that it ignites by itself without requiring a spark, similar to the way a diesel engine operates."

That Mazda had ambitious plans for a generation of engines in years to come that could achieve 30 percent better fuel economy than the current line of Skyactiv engines was already evident back in January this year, when Mitsuo Hitomi, in charge of powertrain development, spoke at Mazda's Yokohama technical center. Discussing goals, Hitomi said Skyactiv 2 will focus on improved internal combustion "If we want to dramatically improve fuel economy from here, the only route is through lean burning," Hitomi referred also to plans for a Skyactiv 3 lineup in the future that may help Mazda comply with 2025 emissions targets.

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Mar 29, 2014
From a Wikipedia article about Homogeneous charge compression ignition:
The unburned hydrocarbon and carbon monoxide emissions are still high (due to lower peak temperatures), as in gasoline engines, and must still be treated to meet automotive emission regulations.
Lean burning is good, but apparently still needs to use a catalytic converter to eliminate pollutants.

Mar 29, 2014
If it's a diesel engine in principle, why not go the logical next inch and make a diesel engine? What's the advantage of running on gasoline?

Mar 29, 2014
Sounds like a good candidate for biodiesel. Or some other non petroleum, renewable fuel.

Mar 30, 2014
Do people not see the obvious chemical incongruity here ?

If this engine is designed to run on the same (or similar) fuels we already use, despite the fuel's octane & despite engine's high compression ratio - then you cannot defeat Chemistry - you WILL get the same amount of CO2, though it might end up delivering exhaust at different temp.

So therefore, to claim:-
..reduce carbon dioxide emissions below the amount generated to power electric cars
per-supposes a major change in fuel & significant indeed.
ie. The fuel must have a greater proportion of H to C than contemporary conventional 'gasoline'.

OR, they are spitting out more CO, which of course is a flaky way to reduce CO2 ;-)

Either that or their metric for
..below the amount generated to power electric cars
needs some serious attention & re-evaluation & useful robust dialectic firmly founded on the Chemistry & of course the Physics of just how much bang for buck we are actually likely to get !

Questions ?

Mar 30, 2014
Mike, obviously you'll get the same amount of CO2 per liter gasoline burned. I believe the point is that you could drive 30% further for the same amount of gasoline.

Mar 30, 2014
Even if it would release less CO2 than an electric it would still release it in the city and it would hinder the development of more green electric sources that would continue making the electric car more and more green. It is ridiculous to think that this would be an alternative to an electric vehicle because of that fact.

Mar 30, 2014
Even if it would release less CO2 than an electric it would still release it in the city

CO2 in itself is not a problem. It doesn't contribute to smog or cause any adverse health effects.

it would hinder the development of more green electric sources that would continue making the electric car more and more green

How? Electric cars aren't exactly the driving force behind advanced renewable energy sources. They just increase demand and make it harder to meet the existing load on the grid.

80% of the world's electricity is still produced with coal, and will be for years and years to come, so there's no point in building fleets of electric cars before they have a clean source of energy. Switching to higher efficiency engines and using natural gas for fuel allows you to reduce emissions faster than building electric vehicles.

Mar 30, 2014
This is peanuts. Until we get weaned out of gasoline, I would suggest that we use MYT as the engine for cars and even flying. Just google 'MYT engine'

Mar 30, 2014
This comment has been removed by a moderator.

Mar 30, 2014
I found a number that was about half that

Then I stand corrected, but does that really change the point? The US makes 71% of electricity using fossil fuels, 49% from coal, 21% natural gas, 1% petroleum.

Almost all of the capacity being added to the grid in countries like the U.S. is renewables - so that balance is changing.

Not really. The peak-to-average ratio of wind power is around 4:1 and for solar power 8:1 and up to 10:1 which means that after about 20% grid penetration it starts to cost exponentially more to use more because we have no storage capacity to capture and use the surplus peak production.

And batteries have significant inherent energy cost (ESOI) which is not counted in.

all of our power be from renewables by mid century


Even if electricity became clean enough by 2050, that's still 36 years and many generations of cars from now. EV's are a niche product for areas with lots of hydro and nuclear. Elsewhere they just do more harm.

Mar 30, 2014
HHO assist in cars is still more economical, as it can be done with today's engines; it has been proven by many. We're getting into the tens of thousands, here.

It also burns cleaner than this 'invention'. Much much cleaner. Zero effluent, which only brings up questions. Questions which have been answered, if you search for it. The minimal answer is: transmutation.

The data behind HHO assist is compelling.

Mar 30, 2014
My thoughts,
(1) need a cradle to grave CO2 foot comparason for the new engine that considers the global market penetration
(2) get rid of the "feel good" mantra for these engines (I'm doing my part buying green cars) and get serious about global CO2 emissions,
(3) see 1 and 2

Mar 30, 2014
We aren't even including the larger carbon footprint created in mining and manufacturing the LI-ion battery.

Mar 30, 2014
With "HCCI system works in a way similar to a diesel engine, using piston compression rather than a spark plug to ignite the mixture in the chamber" apart the fuel, what is the difference with a diesel engine ?
And why there will be less particle and pollution than with a diesel engine ?.

Mar 30, 2014
Please google up the MYT engine, which is real evolution in ICE. It is much smaller, has less parts and uses less fuel for the same power output, therefore it is greener.

Mar 30, 2014
I will add to those who find the Mazda approach is the faster and more efficient means to cleaning things up. If you add ALL of the dirt that comes from both the batteries and the rare earth magnets needed to propel an all electric car, add all of it up and they are more than a conventionally powered gas vehicle. The only way the electric wins is IF it can run for many more miles than is usual for said vehicles. I don't remember the exact numbers but it's silly to even argue. There was a study done by a Norway university published here, at, that spoke to it well.

The strain to existing infrastructure as well would crash the electrical distribution lines. We have an existing petrochemical system that is functional. If the efficiency of gasoline can be increased it might be a very viable and cleaner way to go that makes economic sense as well as treating the environment better.

Mar 30, 2014
dvd, first off, that's NOT their conclusion, read the last two paragraphs, after that one.

It remains to be seen if an EV or Hybrid vehicle will be better for the planet than a petroleum fueled vehicle or not. That very much depends on production methods and recycling as well as how the energy used in it is supplied or sourced.

It is not now, nor has it ever been a rational choice, that was easy, IF ALL the factors are figured into the equation. I'm certainly not saying they can't be a better choice, or will be, but so far, saying that it's an easy choice, is ill informed and ignorant of all the true facts involved.

Mar 31, 2014
total bullshit

Mar 31, 2014

Perhaps countries like Germany and Denmark are giving us the experience we need to figure out how to do this right.

At least they're showing exactly what not to do.

Denmark is among the most polluting countries in terms of CO2 per kWh of electricity produced, in part -because- they're employing a high percentage of intermittent renewables that forces them to rely on less efficient means of energy production such as simple steam turbines instead of thermal co-generation or combined cycle plants due to the need for quick output adjustment.

That's the paradox. When you add intermittent renewables to the grid, they force you to replace baseload generation with less efficient load following powerplants and that results in an overall increase in CO2 output and pollution. One can only attempt to hide this fact by using the "virtual battery" principle, which means pushing the power across borders to be handled by other countries, so your pollution figures would look nicer.

Mar 31, 2014
The bigger point being that we do need to get off of fossil fuels.

Yes, but that's also a red herring in this particular case, because we can't. We simply don't have the technology yet.

Building more electric cars would not decrease overall pollution, because there's only so much clean energy around and the increase in demand will not be met with increase in clean energy because we can't build more hydro power, we refuse to build more nuclear power, and building more intermittent renewables just means we need to use more fossil fuel power in inefficient ways to adjust to the output variations and in the end you end up producing 70-80% of the new power from fossil fuels anyhow.

So building electric cars is just increasing demand for electricity, and that increases pollution. The best they can offer is to move the emissions to a different smokestack.

Mar 31, 2014

The sad fact is that out of the European nations, those who use nuclear power are the least polluting. Norway of course is an exception because they have huge hydropower reserves and a small population.

The ones that don't use nuclear power produce twice as much CO2 regardless of renewables. Denmark is roughly on par with Slovenia. One has 30% wind power, the other has 1.3%.

Likewise with Germany. 25% renewables, makes as much CO2/kWh as the UK which has 11.3%. It's almost like it doesn't really matter how much wind or solar power you have because you lose efficiency elsewhere.

Mar 31, 2014
Foundation got his numbers from where precisely ?
Mike, obviously you'll get the same amount of CO2 per liter gasoline burned. I believe the point is that you could drive 30% further for the same amount of gasoline.
Could Foundation, or might Foundation, some time when Foundation ?
The article states "..generation of engines in years to come.." so surely that cannot be the current engine described or are you Assuming it is, if so then why please ?

Whee did you get the 30% from Foundation in respect of the current engine ?

Re The current engine, at 18:1 CR its not dissimilar to a diesel, would it not be batter to improve the CR & & in respect of the overall package re combinatorial controls on a contemporary diesel as a starting point given many energy effective renewable fuels available or planned are already easily diesel compatible ?

Mar 31, 2014
Even though the tech is similar to a diesel, the gasoline is cleaner burning with less NOx and such emissions than a diesel burning car.

I used to be all gung-ho about electric cars. I really like the simplicity of the motor versus the complexity of the piston engines. However, unless there is some fantastic revolution in battery tech, I don't see electric cars taking over any time soon.

Couple this new engine tech with the fact that alternative chemical fuels (eg bio-butanol) could plug into the already extensive liquid fuel with little or no modification...I think EVs will be a niche market for some time in the future.

Apr 01, 2014
Would you have a source to support your assertion.

I already gave you one. CO2 output per capita is not relevant. CO2 per unit energy is. In your example, Norway is producing a lot of CO2 per capita, but that's only because they have a small population and use a lot of energy for heavy industry like aluminium production. In reality they're about the cleanest country there is because they make nearly all of their electricity using hydropower.

We are learning to integrate renewables on to the grid.

Yes, but at the same time we are trying to run with renewables before we can walk. The new powerplants we need to build -now- to cope with the intermittency have payback times in 30-50 years, which means they're only economically feasible if you keep using them for decades. Renewable energy or not, we have to build them anyways to replace the aging stock, which means we can't get rid of the fossil fuels for another half a century.

Apr 01, 2014
Foundation got his numbers from where precisely ?

It says so in the article.

Whee did you get the 30% from Foundation in respect of the current engine ?

The figure is estimated for the next version. It's 30% better fuel efficiency in respect to this version, which is already more fuel efficient than regular spark ignition engines, so the fuel savings in respect to cars on the market today is greater than 30%.

Apr 01, 2014
dvd, don't you understand that wind generation kills birds? Butt loads of them if you listen to peregrine fund and condor fans. Solar gets in the way of desert tortoise breeding grounds and virtually every other renewable seems to offend some wildlife group or another.
BTW posting a press release as if it proves anything, please, go back under your bridge!

Apr 01, 2014
How long will it take? Many decades - but our fossil fuel infrastructure was not built in a day either.

That was my point. It's highly unlikely we'll get much cleaner electricity by 2050, so a next generation of efficient combustion engines is necessary to reduce emissions until we do.

Your oft repeated premise that we must build fossil fuel generation to back up renewables is simply not true.

We can build renewables in a limited sense without increasing fossil fuel use, but the main problem is scalability and price.

Here is an example of one market that is integrating large quantities of renewables - and guess what? They do not have to build fossil fuel back up for each watt of renewables.

That's because the ERCOT region uses the virtual battery principle, which means offloading the power out of Texas to deal with it by not dealing with it.

The problem with wind power in Texas is that tends to produce at night and not during daytime peak demand.

Apr 01, 2014
And I dislike the term "backup" when talking of fossil fuel load following to renewable energy, because it gives a totally wrong impression of the matter. It gives the impression that the turbines are turning quite steadily and only occasionally dropping, while the opposite is true: the turbines are making high brief power surges with long gaps in between, and the conventional power generation has to fill these gaps in. This is a direct result from the high peak-to-average ratio.

Here's a good representative picture of wind power output from Ireland:

Apr 01, 2014
An interesting approach and options are good because efficiency is often about picking the solution that is just right for a very particular job/niche/application/etc.

Still, how hard can it be to make small [gas] turbines to generate electricity on demand or nearly on demand, and then use that electricity to power an efficient electric motor to drive the vehicle?

and it would hinder the development of more green electric sources that would continue making the electric car more and more green.

This foolish, misguided notion is way too prevalent.

We do not need or want a bunch of dirty coal powered cars today so that we can maybe have "clean" all-electric cars eventually. Some techs may never pan out and yet in the mean time, research into them can still be subsidized.

What's better for the environment is relative to what is actually going on now. Incremental improvements that are real are far better than the insane pursuit of perfection.

Apr 03, 2014
so any time someone shows you a real world example of the success of renewables - you come up with a rationalization as to why that is not a good example.

First, what you showed was technically a dead link. I had to dig up google cache to read it.

Second, it was simply an advertizement piece saying "We've installed so much wind power" without going into any details how the system works or what they're doing to solve the problems.

Third, the Texan wind power system is a sham, just like the Danish system and the German system. They all work by pushing the power to someone else and have someone else deal with it so the wind power producers can get their subsidies.

You are aware right that demand curves for power are not flat lines right?

They largely are. Typically at least 50-60% of the demand is constant. The renewable power is not dispatchable and cannot reliably meet the daily variation, so it digs into the baseload where demand is always guaranteed.

Apr 03, 2014
But really. Let's take Denmark as a yardstick even though they "outsource" much of the pollution problems caused by intermittency to other countries.

The vast majority of EU nations produce more than 300 g/kWh in CO2, Denmark included, with the biggest offender Estonia making 1000g/kWh. The average of the EU-27 countries is 380 grams. Only a handful of small nations, and France, can limbo below the 300 gram bar, and France's secret is that 75% of their electricity is nuclear power.

An electric car like the Tesla S uses 380 Wh to the mile, which is 2.631 miles to the kWh. The EU-27 average emissions for electric cars today would therefore be more or less 144 g/mi, and 114g/mi in Denmark.

Meanwhile the average car in the UK already makes 142 g/mi and small hatchbacks and diesels routinely go around 90-100 g/mi. If you reduce these emissions by 30% you get 100g average and 70g minimum.

So the electric car has a lot of catching up to do before it makes any sense to call it clean

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