New engine control for lower NOx biodiesel emissions

[rfernatt]

Ok, now I want a diesel smart that can run on a high percentage of biodiesel using this technology.

Advanced Engine-Control System Reduces Biodiesel Fuel Consumption and Emissions

[jwight]

There's no free lunch:

We were able to improve the fuel economy with a biodiesel blend while reducing nitrogen oxides to where they were with conventional diesel," Shaver said. "At the same time, we were able to maintain the customary biodiesel reductions in particulate matter emissions compared to ordinary diesel fuel while not increasing noise emissions.

Fuel economy still is problematic, however, because biodiesel has 10 percent to 12 percent lower "energy density," or the amount of energy liberated during combustion, compared to regular diesel fuel, he said.

[sunnyokanagan]

Burning biodiesel in a smart car shows a minuscule increase in fuel consumption. You feel a little power loss, but you can make up for that with a more efficient ECU program and/or high quality Cetane Booster.

Interesting that the article says newer engines with EGR systems actually make more NOx with biodiesel, since the alleged purpose of EGR is to reduce NOx. The MB 0.8L turbo-diesel's EGR system is carp anyway. Some people even delete it. Hypothetically.

[wiltjk]

Another key factor is a recent innovation called exhaust gas recirculation, which reroutes exhaust back into the engine cylinders to reduce emissions. The researchers found that nitrogen oxide emissions rise by a higher percentage in engines equipped with this exhaust-recirculation technology

Tweaking the EGR is the first thing we do after we hook a VAGCOM up to a TDI. My Bio Beetle gets 50 mpg with B20 and 47 mpg with B100. Nothing to complain about for all the benefits.

[rfernatt]

Originally Posted by jwight

There's no free lunch

While it is true that biodiesel will never be as efficient as petro diesel due to the lower energy density, it is certainly not a bad thing to maximize it's efficiency. If BD causes a 20% drop in mileage in a given engine at present and we can get it down close to the actual fuel energy differential then that's progress. A 7-9% improvement over current BD mileage is nothing to sneeze at.

[jwight]

And you get the added benefit of a car that smells like french fries...

[lebikerboy]

No it doesn't smell like french fries, it has it's own smell which
is a lot more pleasant than diesel...

[jwight]

More like fish and chips...?