Did you ever wonder what happened to the "secret" superfuel from IC? Well, I did. Developers of IC² already mentioned "adulterated fuel". Alblaka stated that you could put other things than Fuelcells into Fuelcans with the canning machine. Well, I did some experiments to find out more about it. To not ruin your fun about finding out things about superfuel, I'll put the stuff I found out in spoilers.
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First, the most important ingredients in superfuel are Redstone Dust, Glowstone Dust, and of course Biofuel Cells and Coalfuel Cells.
I tried several fuel recipes. The first one I tried was of course the IC superfuel recipe( 
=Nothing; 
=Gunpowder; 
=Glowstone Dust; 
=Redstone Dust): 
So I combined 2 coalfuel cells , 2 piles of gunpowder , 1 pile of redstone and 1 pile of glowstonde dust. This gave me 51680 EU in a generator.
Then, I wanted to create something out of only dust. I found out you can't begin filling a fuel can with dust. After that, I made several experiments using only 1 fuelcell and 5 pieces of dust/powder. As we all know,a coalfuel cell is worth
12 740 EU and a biofuel cell is worth 4340 EU. Using this knowledge, I found out that gunpowder is worth 11 152 EU if 5 piles of gunpowder are used with a coalfuel cell, but it's only worth 3798 EU if 5 are used with a biofuel cell. One pile of glowstone dust is worth 6908 EU when using 5 piles of it with a coalfuel cell, but only 2350 EU when used with a biofuel cell. Redstone is worth 3788 EU when 5 piles are used with a coalfuel cell, but only 1288 EU when used with a biofuel cell. The difference between coal superfuel and bio superfuel awakened my interest. After a few more experiments, I found out that a pile of redstone with 5 coalfuel cells is worth 2540 EU, with 5 biofuel cells 860 EU. A pile of glowstone dust with 5 coalfuel cells is worth 3820 EU, with 5 biofuel cells it's worth 1300 EU. A pile of gunpowder with 5 coalfuel cells is worth 5090 EU, with 5 biofuel cells 1730 EU. So the kind of other ingredients, the quantity of other ingredients and the quantity of the ingredient seem to influence how many EU the ingredient is worth. Please tell me if you find out a good fuel mixture!
Please excuse the extensive use of emoticons, most likely I will reduce the amount of them later.
Please excuse and tell me any mistakes you find here, I will correct them. Please tell me if this was posted already, I didn't find something like this by searching.
Thanks for reading!
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