I've been reading about WVO contributing more to greenhouse gases than originally thought. Has anyone else been following this debate? Having sad that, I'm talking about the engine burning emissions, not including changing forests into farm land. I thought burning WVO was much better than petro fuels, but now I'm confused. Thanks.

NAY SAYERS ARE USALLY TIED TO BIG OIL.

What comes out of the tailpipe is essentially the same no matter what the fuel source.

There are certainly some differences between Diesel and Gasoline engines. Diesels tend to use less overall fuel (and thus less CO2) than gasoline engines. However, they have issues with smoke and particulates.

One of the complaints is that people doing vegetable Oil conversions tend to gravitate towards the older vehicles for a number of reasons. And, those engines don't burn as cleanly as the newer engines.

The "newer" engines (2007 and newer) include a Diesel Particulate Filter (DPF) which requires a regeneration mode that is less tolerant of biofuels. A lot has been discussed with respect to that elsewhere.

The has been debate on how cleanly VO and biodiesel burn. It depends a lot on the atomization in the cylinder.

The big point, however, is that VO and WVO are from renewable resources. Thus, CO2 is released, and recaptured in a cycle. Many people use the "renewable" as part of their emission calculations, especially for calculating the CO2 impact.

WVO is a form of recycling where a product is used once, then gets a second life. However, there always has been some demand for WVO, just not highly valued enough that there were concerted efforts to collect it. It was used in feeds, and caloric supplements, donated glycerin for soaps, etc.

quote:

What comes out of the tailpipe is essentially the same no matter what the fuel source.

There are certainly some differences between Diesel and Gasoline engines. Diesels tend to use less overall fuel (and thus less CO2) than gasoline engines. However, they have issues with smoke and particulates.

One of the complaints is that people doing vegetable Oil conversions tend to gravitate towards the older vehicles for a number of reasons. And, those engines don't burn as cleanly as the newer engines.

I don't exactly agree. I've run blends of VO, BD and ULSD which tested to ≤10 ppm HC and ≤1% opacity in an '89 Toyota. The techs remarked that it was the cleanest diesel they had tested and that it was as good as a new gasoline car. I've noticed vehicles running V100 that burned 'dirty', so the blends might be cleaner than 100% VO. This is just subjective observation and not from rigorous testing so take it FWIW.

I believe that tailpipe emissions depend VERY much on the vehicle condition. I suspect there is more variation among vehicles than there is among different fuels. Therefore I doubt if any definitive statements about "WVO" emissions can be made without testing each vehicle specifically.