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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.
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.
but not for long. even IF they achieve this.
They are defining the scope of "clean" pretty narrowly here to get this win. One admittedly important metric only -- CO2e, and the comparator is an EV running off a grid that looks like today.
Obviously,
1. there are many other important metrics: particulates, particulates at street level, NOx, NOx at street level, noise, vibration damage, etc.
2. EVs get less carbon intensive over time without doing anything as the mix of power sources shifts more and more towards low-carbon.
On whether the germans or the japanese get there first - at least to a production vehicle, the article states that Merc-AMG have already made it with F1, but the japanese are persistent.
This will be an interesting contest to watch.
They sentenced me to twenty years of boredom
Not like you think, of course.
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.
You can even take the CO2 from the air and turn it back into gasoline. Although that is very inefficient.
But efficiency is not really relevant, as you can store both the CO2 and gasoline for a very long time, and hence do the conversion whenever and wherever you please. Like only in the summer during the day. Or in the desert. (Although of course carrying it via ships and pipelines is a bad idea due to how much mess even a little error can cause..)
It needs no rare earths, no poisonous chemicals (OK, except that gasoline itself isn't the healthiest. But hey, it literally comes out of the ground. :), and also doesn’t explode, unlike batteries (and movie gasoline).
I know this goes very much against popular opinion (as in belief, as opposed to knowledge, or understanding), and might even get me downmodded on this site,
but I find it crazy that we run after batteries, even though they are even worse, just because we are willfully (and militantly) ignorant regarding the above solution.
Why is this desirable? A heavy noisy motor with lots of moving parts - decreasing reliability - requiring harmful chemicals and kicking out pollution at street level.
Not criticising the concept. It's good to see improvements, and the internal combustion engine was an impressive invention, but I think after a century and a half, we should expect it to be replaced with better technology.
The elephant in the room is: regardless of whether EV from green sources or super-efficient ICE, we have too many cars, and they are too big.
I watched in horror at Dieselgate, where folks were quibbling about a minor cheat in small automobiles while they were buying SUVs to go buy their groceries or bring their prole to the school.
I mean: VW (and many others!) cheated on the emission values of their cars and desserve a serious spanking on that (much more than they actually got!), but are making a killing selling SUVs to people that don't really need them: the real problem are we, the customers!
On a long term forecast, electric vehicles will be very very cheap to produce, not just the components are way less, the supply chain and quality control will be way more reduced. There is no way any fossil fuel will ever be more efficient from an energy prepective than a eletric engine. We are at infant stage of tech, and cars are getting has low as 12 kwh per 100 km, I can't even imagine anything better than this. This Mazda engine relies on extreme compression, don't expect the engines to last long
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 (out of my head, I think it's : China, Inda, Australia. Not 100% sure, should google) where there's basically no difference between an EV charging from the grid and a ICE, in every other country including those that still burn fossil in electrical power plant (that's including the US), there's some improvement of efficiency simply by shifting the burning from a small compact ICE that has to do compromises on lots of other parameters (weight, size, quick reaction, etc.) to a huge power plant that is more or less exclusively optimized for efficiency.
And then you have European nations where you can find a mix of power source that relies a lot on renewable sources (solar, wind, alpine hydro) or sources with a much smaller mass of pollution output (nuclear).
Also the way power is produced isn't the only advantage :
EV use regenerative breaking, being able to use significant fraction of the kinetic energy to charge back their battery pack.
(Slight tangeant, Swiss example : two high speed train going down from the Lötschberg tunnel can power one train going up "for free").
That is extremely usefull in stop-and-go situations (in city driving, commuting on busy highway with traffic jams, etc.) whereas these situations are killer for ICE efficiency.
Also, going out for a spin on the weekend? I prefer my motorbike, thanks. Perhaps I'll have to have it modified to run on bio-fuels.
Depends on how the biofuels are produced.
- As a way to make something useful out of argigulture's waste ? (We're doing so in several European countries) Yup, that's definitely an improvement.
- But some countries (US among other, I've read) do cultivate plants for the sole purpose of producing ethanol. That's cultures which are requiring additional soil exploitation, and a competing with food production.
It's a bit more problematic in the long term regarding bio-diversity, etc.
"Sufficiently advanced satire is indistinguishable from reality." - [Tips: 1DrYakQDKCQ6y52z6QbnkxHXAocMZJE61o ]
Mazda's engine achieves a compression ratio of 14 to 1 which I think is spectacular for a road going car. It's the same as their diesel which has evolved in the other direction.
Racecars can get higher compression but their idle is very high, which avoids low rev knocking and they use higher octane.
Come on guys, is nobody interested in the mechanics of this thing?
All very nice.
But most people can't afford a new car anyway, and most of the cars on the road are 5-10 years old minimum.
Also, less than 1% of NEW CAR SALES are electric today (worldwide, unless you live in Norway). Literally 99 petrol cars to every 1 electric sold, even today (taken worldwide). How long is it going to take, even assuming some kind of exponential sales growth, before a significant portion of the on-the-road vehicles are electric?
To make a dent in the existing market is going to take a decade minimum, and even then most people will still be driving a fuelled car instead of electric.
Whether it pays for itself or not, it really doesn't matter if you can't afford it, people aren't buying it, production isn't there, and there'll be a glut of cheap petrol cars even when they do start taking over.
Traditional cars are going to be being made and sold for a LONG time yet. You aren't going to be able to change that. And a car that Mazda designs now will be sold in 5-or-so-years time, most probably, which means they can sell it for 5-or-more years. It's not stretching a sunk investment, it's just ordinary business-as-usual.
I'm sure they have some R&D in electric cars and will start producing more electric models, but they will be funded by traditional sales for another decade at least. And it will be maybe another decade after that before those cars disappear from the roads.
And the point at which electric cars are suddenly a significant portion of the market? They will attract all the normal taxes that loss of traditional cars will cause - in the UK, that means heavy taxes on petrol, road taxes, congestion charges, etc. that electric cars are currently avoiding or exempt from. What will happen is that electrical use will be taxed, maybe even just car-charging-use (e.g. at stations, or home units drawing more than a certain amount).
The countries lose a LOT of tax if electric cars become prevalent, and they're currently subsidised, in effect. That will rapidly switch as they become available in such numbers that momentum drives sales. To make up that lost tax, be prepared for HEAVY high-energy-use taxation, or more toll-charging, or even paid road-usage-tracking to charge per mile. Sure they'll also raise tax on traditional cars too (to "penalise" the pollution that they are being fined for by international agreements) but that's short-lived.
And they'll be justified in raising energy tax - someone has to put in place enough infrastructure to charge all those things which is going to REALLY whack peak load and maybe even change the timing of peak usage entirely.
>> 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.
aaaaaaa
They are fudging some number to tout this efficiency.
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
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.
Also, just because an EV is fun to drive, doesn't mean that IC cars *aren't* fun to drive.
No argument from me.
Hop in a Ford Focus Sport or a Golf GTi and tell me it isn't fun.
We'll I've owned a GTi and it wasn't exactly mind blowing. I didn't hate it but it was just a hopped up econobox with the various compromises that entails. Hot hatchbacks try to be all things to all people and to my mind they fail in that for the most part. The Mercedes SLK I had was MUCH more fun (albeit less practical) to drive. It was faster, cornered way better, looked better, and did the one thing it was designed to do rather well. If you can only afford one car and need something small and practical with a bit of a kick then a hot hatch isn't a bad choice but as fun cars go they aren't the best option out there.
Even better, jump in an Audi Quattro and tell me what you think.
I've owned one of those too a while back. Performed well enough but fun to drive? It was ok in some conditions. Better than a hot hatch but worse than a proper sports car in the dry. Fairly fun on gravel and in sloppy weather.
Or find yourself a Group B rally car and take it for a spin on a dirt track.
Seriously? You're comparing a purpose built race car to a street legal EV? I'm sure it's amazing to drive an F1 car too but let's keep it realistic.
EVs aren't an evolution of fun, they're not the next generation of fun, they're more of a new branch of the family tree. They're going to replace whole classes of IC cars, e.g commuting, but they're not going to replace them all.
Yes there will probably be IC cars for the foreseeable future as long as those who use fossil fuels aren't required to pay for the full cost of the pollution they generate. My guess is that EVs will eventually account for the majority of cars with gas/diesel cars becoming specialty vehicles for tasks EVs aren't well suited for. (remote locations, extreme climates, etc) The advantages of EVs just make too much sense for most people if they can get the fueling infrastructure issues sorted out. How long this will take is anybody's guess but I'm thinking at least 30 years.
You can back out ICE efficiency from the EVs on the road. Let's use the Nissan Leaf (you'll see why later). EPA rating of 30 kWh per 100 miles. 112 MPGe combined, 101 MPGe.highway. Top speed of 93 MPH.
30 kWh per 100 miles = 108 Megajoules per 100 miles. Since we're trying to do a comparison and ICE cars don't have regenerative braking, we need to compare the highway mileage. Since the Leaf gets 101 MPGe on the highway vs 112 MPGe combined, this works out to (112/101)*(108 MJ) = 119.8 MJ per 100 miles on the highway. Note that this is energy stored in the battery. To do the comparison, we need energy at wheels to the ground.
Electric motor + inverter efficiency is typically about 85%-93% (page 35). That's for a Prius' motor (the only one I could find detailed stats for), but they're all pretty similar at these levels of power output. Since there's no gearing, if you align the Leaf's top speed of 93 MPH with 6000 RPM, then the highway speed of 55 MPH corresponds to (55/93)*(6000 RPM) = 3550 RPM. Which puts us right around 90% efficiency.
I couldn't find any numbers for battery discharge efficiency. Battery charging efficiency for a Tesla with the home charger is about 85%. Battery discharge efficiency is typically a bit worse (even more so at higher loads, which is why jackrabbit or ludicrous mode starts kill your rnage). so go with 80%. (For those of you complaining this is too unfavorable to EVs, a lower discharge efficiency here corresponds to lower ICE efficiency later on.)
So 119.8 MJ from the battery becomes (119.8 MJ)*(90%)*(80%) = 86.3 MJ per 100 miles wheels-to-ground. The extra energy is lost as heat to the battery, wiring, inverter, and motor.
Gasoline has an energy density of 34.2 MJ/L = 129.5 MJ/gallon. To figure out how many gallons were used in 100 miles, we need the MPG of a gas-powered Leaf. Fortunately we have one - the Leaf's aerodynamic and rolling resistance is almost identical to the Versa since it shares the same body and frame (I had to go back to 2014 to get the hatchback version with a regular transmission). Highway mileage is 35 MPG. Meaning (129.5 MJ/gal)*(100 miles)/(35 miles/gal) = 370 MJ worth of gasoline consumed per 100 miles.
Overall highway efficiency of the ICE and drivetrain is then energy wheels-to-ground vs energy in the gasoline. (86.3 MJ)/(370 MJ) = 23.3%. It's rated at 26 MPG city, so overall efficiency in city driving is (26/35)*(23.3%) = 17.3%. A far cry from the 12% you came up with.
We can also calculate overall efficiency for the EV, from energy source to wheels-to-ground, just like we calculated it for the ICE vehicle from energy source (gasoline) to wheels-to-ground. The average efficiency of a coal plant is about 33%. The average efficiency of a natural gas plant is about 43%. Power line transmission losses are about 5%. As mentioned before, charging efficiency (for a home charger) is around 85%, discharge efficiency around 80%, motor efficiency around 90%. To get an overall efficiency of (33% or 43%)*(95%)*(85%)*(80%)*(90%) = 19.2% or 25%. If you use a fast charger like a Supercharger station, it's even worse, since the charging efficiency is even lower (more of the electricity is lost as heat) the more quickly you charge the battery.
So an EV powered by electricity generated from fossil fuels isn't any more energy efficient than an ICE vehicle. The reason it's cheaper to charge an EV is almost entirely because gasoline is damn expensive for an energy source. Coal costs about $50/ton and contains ab
new clean engine with some batteries and electric motors and you can make a great pluggable hybrid car.