'catalytic effect' of Biodiesel

[Ivan]

A friend of mine told me that biodiesel can boost the efficiency of standard diesel. I've tested this out, and from my own findings it does seem to be true. He told me that maximum mpg is obtained at around 20% biodiesel, 80% dino diesel mixtures. Of course, mpg isn't really the best measure of the real optimum ratio, as biodiesel is an oxygenated fuel, so gives fewer mpg than diesel.

However, at 15% Biodiesel, 85% diesel, at 70mph, I saw an improvement from (computer-indicated mpg (which reads approx 10% over-optimistic)  63mpg to 68mpg - measured over 700miles.

A few years ago we did tests on a rolling road with sensitive fuel balances, and fixed speed/load conditions, and found that introducing LPG into the airstream of a 1996 diesel pickup improved the overall fuel efficiency by around 10%. LPG added to diesel in this way usually reduces the black soot, particularly under acceleration, so we assumed that the additional efficiency was down to a more complete burning of the diesel fuel. I guess the same effect might apply to biodiesel - it's noted to have a much reduced particulate output by comparison with dino diesel.

Just thought I'd pass on this info as it might benefit other drivers. For example, if only have a small amount of biodiesel available, it might be better to mix it 20/80 with diesel, rather than run occasional tanks on 100% biodiesel.


Ivan

[Bob]

Brilliant Ivan.  Thanks

The LPG in the air stream sounds a bit like the method for using woodgas in a diesel?

[PEMTEK]

yeah its called fumigating the intake, 

A company i worked for a few years ago did some work on a very big engine designed to run on diesel and nasty waste gases produced from plastic making to make electricity for the plant.

Phil

[Ivan]

Common Rail Diesel Clio, At 70mph:

On diesel                              - 63mpg
On 80% diesel, 20% biodiesel - 69mpg
On 80% biodiesel 20% veg oil - 60mph
On 100% biodiesel                - 60mpg

Energy content - biodiesel 38MJ/kg, veg oil 37MG/kg, diesel 45.6MJ/kg

All readings taken on digital mpg meter (which over-reads by about 10%), averaged over at least 200miles.

The lower readings for biodiesel and veg oil are due to lower energy content of fuel. The higher reading for 20% biodiesel, 80% veg oil is apparent demonstration of the catalytic effect - anyone else care to test this? or test it with 20% veg oil 80% diesel mixture?

[stephen]

Tonight I put 20% in my bro inlaws car and had a crafty look at the on board mpg.  He has no clue it may improve his mpg and as he does the same trips every week it will be interesting to see what his computer says next time i fill it up.
Current 44mpg on normal road diesel.  lets see in a week

[Ivan]

Look forward to seeing the results.

[stephen]

I have sinned... I have put 100% Diesel in my car and ran it for the first time since I got it.  Oh dear whats worse it was M way prices 111.2   wow. :-

Stephen

[Chug]

Biodiesel has a slightly lower calorific value than diesel and so more is used for the same power output, many users who religously log there mileage/consumption report slightly lower fuel consumption but don't mind as it's much cheaper.

peace n grease
Chug

[stephen]

Hi list,
I have noticed over the past week or so that the car has not pulled as it should and its been a bit of a pig to start when luke warm.  Solution replace the fuel filter.
Now a normal car this is a 10 min job.....Not on a freelander. jack the car up take the rear wheel off take out the fuel filter and pump (one assly) then smash the hell out of it (sorry drift) it out then replace.....2 hours and 2 engineers.
Welkl here is a few pics of the filter thats inside the case.  There was no residue on the paper as I had anticipated.  Goes like a little rocket now.

The end thats still fixed is the fuel in end.





Stephen