You'll need to drink a bunch of water to generate all this piss.

How much energy will be lost due to needing to isolate or contain the unwanted by-product gasses from the reaction?

Also... what if I want a power booster on my unit? Will the device come with a toilet seat attachment for producing "nitro methane" from solid waste?

Actually, this is interesting. I followed your link Infringer and it gave link to another article that gave a schematic of the process. Notice that Potassium Carbonate and nitrogen are the other byproducts along with the hydrogen from the process. This must mean they are adding potassium to the reaction. Probably potassium hydroxide, I am not sure.

So throwing up a few calculations we get:

Urea: CAS# 58069-82-2
CH₄N₂O
MW= 60g. / mole



2 Moles H2   X  22.4 Liters H2     X   Mole Urea       =    44.8 Liters H2
Mole Urea             Mole H2            60 grams Urea        60 grams Urea     


 (0.95) X (44.8 ) =   42.6 Liters of H2 / 60 grams of 95% Urea   

or (0.05) X (44.8 ) =  2.24 Liters of H2 / 60 grams of 5% Urea (URINE) 

This looks to me like just a novel way of processing waste urine and getting a hydrogen byproduct out of it.  Urine would have to be separated from other human waste, which we don't normally do, so this seems a bit unpractical. I haven't been able to get at the full article yet so I don't have all the details of what they had in mind for this process, but I guess it is just processing a human waste product and getting out useful byproducts of nitrogen, hydrogen, and potassium carbonate; which can all be sold.

My guess is that the potassium is added to cleverly bind up the carbon and oxygen leftovers that would be released as carbon monoxide or carbon dioxide.

Not quite as simple as just pissing in an electrolyser though is it? Some thought and consideration has to be given to this - the first being that most home built electrolysers are common duct for hydrogen and oxygen, so-called HHO.

The chemistry is important as I don't believe we would be getting oxygen from urine. Rather we would be getting hydrogen and other unwanted, probably unpleasant gases which we would need to do something with (preferably not breathe). Furthermore, unlike an electrolyte in water that does not get used up, I believe we would soon be left with just water as the urea would actually get used up.

It will therefore be more complicated an electrolyser design than what most of us already have, plus there is the consideration of any toxic gases that may be evolved. So pissing in an open duct electrolyser and 'just doing it' might not be such a good idea until we know what else apart from H2 is evolved, and what the implications are.

That said, the efficiency of obtaining hydrogen this way would appear to be over 3 times that of standard electrolysis, which can't be a bad thing as long as we're not going to be poisoning the air we breathe.

EDIT
Nevermind

So a refrigirator sized unit "produces" 1kW, and a vehicle can run on [the technology] 90mpg.

That's a big of a big leap for my simple self. I'd be more interested to learn if the vehicle would carry urina as fuel, or would tank the product of the electrolysis, like a hydrogen fuel cell.
If the power in really is smaller by a significant amount that what a combustion engine would squueze out (at curent engine efficiency, I think it will be tight), the positive DIFFERENCE in power would be what our cars would run on, H from urine, on demand. I may over-simplify or invert it, but I think it's important to at least try and say things the way they are.

Quote from RR

Urine would have to be separated from other human waste, which we don't normally do, so this seems a bit unpractical

No we certainly don't, and I certainly wouldn't but - and excuse my unlady-like language - we're only talking about pissing in an electrolyser... not shitting in it! 

see a bit of that up here in farmland, mostly ammonia and hydrogen though instead of nitrogen.

"EXAMPLE 2

Referring to FIG. 3, a cyclic voltammetry experiment demonstrates the electrolysis of urea and urine in an alkaline electrolyte composition. The alkaline electrolyte composition was 5 M potassium hydroxide, the anode was electrodeposited nickel on nickel gauze and the cathode was platinum foil. The cycling rate was 10 millivolts per second. The concentration of urea was 0.33 M, which is equivalent to an average concentration of urea in human urine. A baseline experiment was performed on the 5 M potassium hydroxide alone. The figure indicates that the electro-oxidation of urea and urine behave similarly. As such, the other contents of urine do not appear stop the electro-oxidation of urea.

Under the conditions existing in the above electrolytic cell, a hydrolysis reaction may occur. This would convert urea into ammonia and carbon dioxide. The hydrolysis pathway becomes favorable with increasing hydroxide salt concentration and increasing temperatures. For example, urea samples contained in 0 M, 1 M, 5 M and 7 M KOH at 50° C. for 89 hours produced 0.7%, 4.2%, 27.4% and 36.7% hydrolysis, respectively. A 7 M KOH sample of urea at 70° C. for only 24 hours provided over 95% hydrolysis. The hydrolysis reaction is shown in the following reaction.


CO(NH 2 ) 2 +H 2 O→2NH 3 ↑+CO 2 ↑ (Overall Hydrolysis Reaction)

Thus, reaction conditions can be modified to promote NH 3 production over H 2 production using an applied voltage. In some instances, H 2 production will be preferred."

http://www.freepatentsonline.com/y2009/0095636.html

ironhead, you almost made me spit out my soda. 

Group,

Experience from my youth with rabbits, it would be easy to
construct waste separating housing. You get meat, solid
fertilizer and now ENERGY!?  !!! If memory serves???,
rabbit urine was concentrated. A pregnant cow if you could
capture the urine they release what seems like a gallon or
more each time they let go. Also extremely strong P smell...
+++++++

Everyone that says NOT to P in your booster cell is right.
First one side of each plate or other surface must be nickel
plated and the cell voltage must be reduced to 0.37 volts

will pulsing continue to increase efficiency? The frequency
will have to be determined. Then once the water electrolyte
is depleted of urea it will have to be removed.

So far sounds easy enough for anyone thats made a water
hho system...  except now we can use galvanized maybe..

For those that want to use Human P, morning P is strongest.

I have my fingers crossed that we get CO out too!, 2/1 ratio
as its excellent medium compression engine fuel. Just mix all
with air and burn. The nitrogen, hydrogen and carbon monoxide
is like woodgas or producer gas BUT would seem clean from the
start UNLIKE woodgas or other producers.

Dave