That is a pretty large document you found there. I do concede RD is less energy dense by volume; my initial assumption that it wasn't was based on the unfounded assumption petroleum diesel did not contain aromatics. For some reason I thought petro companies fractioned off all the naptha and aromatics when refining diesel.I found this document online last night. It has more information on RD than I've ever found in one place. Prepared by a consulting agency, very detailed with multiple data sources including test results with blends like R20 and R50.
Should dispel some of the myths and false marketing claims by vendors of RD. Interesting to note, not all pollution constituents are reduced in the test engines and any improvements can be negated based on engine load or duty cycle. Some engines measured higher pollution constituents running RD or blends which was unknown to me.
RD has sulfur content an order of magnitude or more lower than D2. Less sulfur on your injectors and less sulfur dioxide in the air. And how about that cloud point of -27 degrees Celsius compared to D2 - 6 Celsius. Sounds like if you're driving a tank through siberia or a truck through michigan in the dead of winter you'd want RD for that cold start.
As Cumins stated in the document: "Engine performance remained stable and consistent while using RD. Cummins’ customers “should not expect to see any differences” when using it instead of petroleum diesel, except they MAY experience a “fuel economy detriment of 0 percent to 6 percent” when using neat RD, DEPENDING on the specific application and engine duty cycle."
The affect is cited as dependent on numerous variables. A few percent loss in efficiency I consider small enough to be negligible. Personally I have not noticed. A few percent is lost in the noise of other variables during normal driving conditions. Personally measuring these parameters in a lab setting with my vehicle and controlled variables is beyond my desire. If the economy hit were 20%, yes maybe I would care. But "MIGHT" be 0-6% "DEPENDING" on engine cycle? Don't care.
Irrespective of all these different fuel properties, whatever small loss of power or efficiency there may be is not something I care about because this was never my purpose for buying it. I'm not going to get my panties tied up feeling personally deceived because of what some marketing kid decided to plop on some brochure. It is not necessarily false to say RD can produce more horsepower or torque. Will it always at all engine speeds in all engines? Maybe not...and I don't care. The cold start benefit is 100% true by all measures. But do I care if anyone uses this in their marketing? No, I DGAF about the marketing department for any product ever and never have precisely because marketing sadly always gravitates toward ingratiating petty desires of petty people. If I made a marketing flyer for people like me it would say one thing "Do you want basically the same product without the risk of petroleum pipelines rupturing somewhere near you?"
My one and only purpose is to avoid using petroleum and I don't think avoiding it is petty. Crude petroleum is noxious. In no circumstances should we be piping toxic sludge under our oceans and above our aquifers. If liquid fuel can be made other ways it should. Now we got a new oil spill in SoCal. Every year somewhere. All the time. Having toxic sludge showing up in my backyard is not something I seek to increase the probability of. An entire housing tract in Arkansas was ruined by a leaking oil pipeline a few years back; and then you need to clamor for legal culpability from the company just to get the proper value for the home that their negligence destroyed. Why put ourselves through this if there is another way? Why even risk slacker pipeline operators spilling crude if we can avoid it altogether? It seeps down well casings and into aquifers; it goes everywhere. For a 2% volumetric efficiency boost on your commute you would risk crude petroleum contaminating your personal drinking water and that of everyone's children for thousands and thousands of years? Is that really a sound cost benefit analysis?
Fuel properties will always be variable and no one fuel is going to outdo another on every single property. Power, efficiency, cold starts, emissions, etc etc. Drag racers swear on their ethanol; yes its volumetrically less energy dense than gasoline by quite a large margin, but I see guys buying it all the time and they claim to put their cars on dyno's and measure more peak HP. And more power to em, no pun intended. No one was ever troubled by an ethanol spill....or a corn spill.