Featured Mazda competes for thermal efficiency against Toyota with Skyactiv-Z

Also activated carbon canisters and such on the vehicle itself that trap the more-prevalent-to-evaporation gasoline.

 

I think of clean diesel in the same vein as "clean coal".

 

Oh brother, love it when people talk in absolutes. "My color blue is the best". "My Generation Prius is the best". "My view of diesel is the best".
never gets old

 

It's possible. Just not worth the effort with other options available.

Diesel for true cars has the same issue. If fuel economy and emission regulations aren't rolled back, it may become less of an issue with future gasoline cars.

The testing that revealed VW's cheating showed a BMW diesel meeting its emission rating.

They can also run on vegetable oil, biodiesel, and hydrocracked vegetable oil(HVO). The latter is drop in for diesels on the road. Alcohol fuels aren't for gas cars.

Depends on the job and needed tools. If the goal is reducing carbon emissions, mild diesel hybrids are the most economical option.

Europeans wanted efficient, economical cars because of higher fuel taxes. The governments taxed diesel less for the same reasons it is taxed lower in the US. Concern for global warming was also on some minds early on there. Other emissions were a concern, which is why they had ULSD years before the US.

And they wanted that before the year 2000. Toyota didn't get serious about spreading hybrid technology to the line up there until the current Corolla came out in 2018. They were selling diesel Rav4s instead of the hybrid that came to the US.

Domestic car companies just had more sway than they should have in holding cleaner emissions in check. Which is also an issue here.

 

Looks like someone's both not looking very hard - and not reading posts that try to help with a basis of knowledge. Maybe read posts above? post #4 refers to the plug-in hybrid diesel Volkswagen that gets well over 200 MPG. So yea - over 10X better than the alleged "only one in the world". It was a limited production but it shows the potential for diesel phev's.

 

Clean coal, clean kerosene, clean diesel, clean gasoline, clean jet fuel, clean propane, clean natural gas, it's all the same, really.

 

'Never' is rather absolute

 

infinite fuel? how dishonest - electrons have an equivalency against liquid fuels. Roughly 30kWh factoring dc/ac & AC/DC conversions. thus a quantifiable cost for both fuels going into the tank or battery

Hate to be redundant, but once again - this whole nonsense about Mercedes fails to address the high efficiency of the low production Volkswagen PHEV. But it's obvious that's not going to be contradicted, but rather ignored?

Sorry it's so painful to acknowledge diesel has its place and it's efficiencies, and can be dirty or clean just like gasoline turning on various scenarios.
Personally, a small diesel running constantly after charge depletion is what gives diesel its greatest efficiency .... (constant running versus start-stop) & paired to a plug-in vehicle to keep a battery charge sustained most of the time?
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You'd get around 30mpg in that. If you could keep from making use of the 6.4sec zero to sixty. It is a power hybrid, making it not directly comparable to a Prius.

Most of the diesel hybrids listed here are PHEVs.
Top 9 Best Diesel Hybrid Cars of 2025 | Carwow

The popular PHEV models(not just diesel) are power hybrids that don't do much better than the ICE model. Which lead to PHEV sales not reducing carbon emissions. They may not be popular currently.

Toyota's diesel is 44% thermally efficient. It came out a decade ago.
Toyota's Revamped Turbo Diesel Engines Offer
More Torque, Greater Efficiency and Lower Emissions | Toyota Motor Corporation Official Global Website
Toyota GD engine - Wikipedia

Efficiency isn't the only quality of an engine. Without the electric side, which increases the drivetrain price to diesel levels, a 1980 diesel Rabbit could beat your car in a race.

Fuel costs are regional. California might have the closest spread between diesel and gasoline in the US. Price per mile is more likely to favor a diesel there. Then for work vehicles, diesel efficiency doesn't drop off as much as gasoline with loads.

Toyota is spinning away their lack of foresight into battery supplies with the argument they can build more hybrids and reducing carbon emissions more with the batteries they, than if they built plug ins. The study that supports that concluded diesel mild hybrids were the best bang for the buck of a limited battery supply for carbon emissions.

The EU's use of blended economy ratings is total BS. The US realized the error in that after one year.

That out of the way, The VW X1's hybrid efficiency is 120mpg, perhaps a little higher. Though that might be under NEDC.

Ford had a couple diesel hybrid prototypes back in the early 2000s that would have qualified for a SULEV rating.

Except for how they all burn differently in an engine.
I said Europe cut sulfur in diesel fuel long before the US did. It's because lower sulfur means less particles coming out the tail pipe.
If clean emissions is truly your concern, you should be converting your car to methane/natural gas.

 

Of course these things are misleading, they are meant to be. That is why people came up with the whole mpge thing, and charge sustaining mpg.$/km or $/mile of fuel and maintenance are other metrics.

IMHO the vw was a brilliant engineering exercise, Diesel was used because it has more energy/liter than gasoline and vw was pushing diesels at the time. In the real world outside of heavy vehicles, diesel makes little sense in a phev. It adds more weight than a gasoline engine, has higher maintenance if its a clean diesel. VW's non exotic diesel has a thermal efficiency of 42% about the efficiency of the engine in the new prius, but diesel has 16% more energy than E10 gasoline. In a non hybrid the torque matters a lot, not so much in a hybrid or phev. mercedes has shown with their f1 car that a gasoline engine in a hybrid can produce 50% thermal efficiency, but again that is an exotic engine so more expensive.

 

Right. And each has its pros and cons. But overall, hydrocarbons and hydrocarbons, and with enough emissions tech the exhaust should be about the same.

What I mean is don't throw out a technology just because it's not as good as another at present. For an example, if the NOx and PM emissions can be eliminated in a diesel, that would open the doors to lean burning, high compression gasoline and CNG vehicles.

Natural gas is easy to burn clean. Diesel fuel is more difficult. But diesel engines are more efficient and can use biodiesel.

Will biodiesel some day be the solution? Maybe, maybe not.

Of course there is also natural gas that can be taken from cattle.

But I'm talking about possibilities in the future. You are right that if you want better emissions now it's best to look to something like CNG, if not BEV.

 

Top Gear gave a review of the 300 d e Mercedes plug-in diesel as well

https://www.topgear.com/car-reviews/mercedes-benz/e63-amg/e300de-se-4dr-9g-tronic/first-drive

Top gear - haters of all things that are plug in ..... thats got to cause diesel haters grief no end.

https://www.topgear.com/car-reviews/mercedes-benz/e63-amg/e300de-se-4dr-9g-tronic/first-drive
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