Mazda Says Its Next-Gen Gasoline Engine Will Run Cleaner Than An Electric Car (popularmechanics.com)

schwit1 shares a report from Popular Mechanics: Mazda is staking much of its future on the continued existence of the internal-combustion engine, with clever tech like spark-controlled compression ignition set to debut in Mazda's next-generation production-car engine, Skyactiv-X. But the automaker is already thinking even further into the internal-combustion future. Automotive News reports that Mazda is working on a new gas engine, Skyactiv-3, which the automaker says will be as clean as an electric vehicle. Speaking at a tech forum in Tokyo, Mazda powertrain chief Mitsuo Hitomi said that the main goal with Skyactiv-3 is to increase the engine's thermal efficiency to roughly 56 percent. If achieved, that would make the Skyactiv engine the first internal-combustion piston engine to turn the majority of its fuel's energy into power, rather than waste due to friction or heat loss.

To date, the most thermally efficient automotive internal combustion engine belongs to Mercedes-AMG's Formula 1 team, with an efficiency of 50 percent; AMG hopes the F1-derived engine in the Project One street-legal supercar will achieve 41-percent thermal efficiency, which would make it the most thermally efficient production-car engine in history. Automotive News says Mazda's 56-percent goal would represent a 27-percent improvement over current Mazda engines. Hitomi didn't provide a timeline for when Skyactiv-3 would reach production, nor did he specify how Mazda hopes to achieve such an improvement. Mazda's claim, that Skyactiv-3 would be cleaner to run than an all-electric vehicle, is a bold one, and requires some unpacking. Mazda bases the assertion on its estimates of "well-to-wheel" emissions, tallying the pollution generated by both fossil fuel production and utility electricity generation to compare Skyactiv-3 and EV emissions. Such analysis reflects the reality that, currently, much electricity is generated through fossil fuels. In regions where electricity comes from wind, solar, or hydroelectric, the EV would clearly win the argument, but that's not the case for many customers today. If Mazda can make a mass-production internal-combustion engine that achieves more than 50 percent thermal efficiency, it will be an incredible feat -- and would likely help guarantee the piston engine's continued survival.

Comments

Re:power generation

[drinkypoo]

Thanks to green party opposition to nuclear power, we are still burning coal (which creates more residual radioactivity than nuclear, but that's another story).

We aren't using nuclear because it is unprofitable. No private entity will insure them, so We The People have to do it. Decommissing always costs dramatically more than it's supposed to, and uranium is the least concentrated ore we mine so the environmental impact is always vastly larger than it is supposed to be.

Had we embraced nuclear energy, we would not have coal, oil or gas power plants anymore. They would simply be too expensive.

The only way to make fossil fuels more expensive than nuclear is to make people pay to fix all the carbon they release. But we're not doing that. Therefore, nuclear cannot even begin to compete on a price basis.

By the time their super-efficient cars hit the roads, we will hopefully be more advanced and the "cleaner than EV" claim is ancient history.

Yes, we hopefully will have more wind and solar power installed by then. That's far more advanced than baroque arrangements of steam turbines and radioactives. What year is it?

Re:Gasoline IS actually cleaner ... technically!

[geoskd]

But burn it cleanly in a fuel cell, capture (and perhaps compress) its exhaust gases, and convert them back into gasoline in a plant, using nothing but electricity from sunlight, and you got a perfectly clean, infinitely recyclable process, and a fuel that has *much* higher energy density than batteries.

The part you missed is how that process is only 5% efficient at converting sunlight into kinetic energy in the car. The equivalent process for EVs is around 20% give or take. The only two advantages that Hydrocarbon fuels have over pure electric are energy density of the fuel, and the fact that we can pump the hydrocarbons out of the ground in a form that requires relatively little modification to use as the fuel.

Continuing improvements in batteries are wiping out the first advantage, and the second advantage is strongly offset if not completely wiped out by the inherent dangers of the open cycle of burning fossil fuels and releasing the waste products into the atmosphere.

Totally Wrong

[stooo]

>> Mazda powertrain chief Mitsuo Hitomi said that the main goal with Skyactiv-3 is to increase the engine's thermal efficiency to roughly 56 percent.
Yeah. Not really.
A typical gasoline engine may have an efficiency of 20-30% at best.
The maximum efficency of an otto cycle gasoline engine is 40-47%, which is limited by physics.
More would mean a different cycle needs to be used. You can't beat entropy.
https://physics.stackexchange....

Moreover all these efficiencies are totally misleading and completely wrong for an automobile.
The real efficiency of a gasoline engine may be 30%. But the real average efficiency of a gas engine in a car is no more than 12% !!!!
Why ? because this top efficiency is only achieved at a single point in the motor torque/rpm graph.
At all other regimes, the efficiency drops like a rock into the Marianna trench.
The real world gas powered engine efficiency is 12% at best. Diesel achieves 15-17% at best.

prototype test drive

[Chrisq]

There is a review of a test-drive of a prototype from autocar. It is a "Spark Controlled Compression Ignition" engine, which uses a compression ignition and spark in some circumstances and spark ignition in others. In another article they say:

One is the continuous use of spark plugs. These ignite the mixture conventionally when the engine is cold or operating at high revs but, in lean burn mode (about 80% of the time), the spark ignites a pulse of richer fuel. The resultant fireball lights the ultra-lean mixture as it’s compressed.

According to the test drive it's characteristics sound good (low end torque and high revving) but they were unable to verify fuel economy claims.

Re:Efficiency

[haruchai]

but let's try to charge them off wind/solar please?

Which is already happening in several countries (e.g.: hydro is popular in the Alpine regions of Europe).
You know, not every nations produces it's electricity by burning coal.

Otherwise you're shifting the efficiency problem from your engine bay to the grid. I hate smug EV drivers boasting about "clean" driving. They get all flustered when I point out that grid-charging has all sorts of issues from coal-fired electricity.

According to research (damn, I have to keep the link under hand), except in a few countries that have a horrible mix of sources of electricity and burn too much fossils

UCS has been evaluating & tracking how much mpg is needed to match an EV on a grid-level basis
http://blog.ucsusa.org/dave-re...

Unless Mazda has their super-duper engine ready tomorrow, they're fighting an uphill battle with an elephant on their backs.
In 2009, even on the worst grids, an EV would been about the same as a 35 mpg car.
Fast forward to 2014 (there's a slider on one of the images on the page for comparison) and you're looking at only 2 grids where a 40 mpg car is better than an EV and if you look at the most populous areas, you need a 75 mpg car to achieve parity.