"The energy efficiency of water electrolysis varies widely with the numbers
cited below on the optimistic side. Some report 50–80%. These values refer
only to the efficiency of converting electrical energy into hydrogen's
chemical energy. The energy lost in generating the electricity is not
included. For instance, when considering a power plant that converts the
heat of nuclear reactions into hydrogen via electrolysis, the total
efficiency may be closer to 30–45%, although the inefficiencies of
powerplants in turning heat into electrical energy is not usually included
in efficiency, so the former measure of 50-80% efficient is probably a more
So if you are running this off your diesel engine which is probably running
at best 40% efficency, then converting some of that energy into electrical
power to run an electrolysis cell at 50% - 80% efficient (and I would say
more likely 50% if it's home made) then the production losses are likely to
quickly overwhelm any actual performance gain. There *may* be some slight
cost gain seeing as the engine may use a bit less fuel and water is a lot
cheaper, but I am dubious of that at best without numbers to back it up.
Also on the topic of LPG injection.
"Even at full output a diesel engine runs about 50% lean of stoichiometric
to avoid black smoke production, so there is a substantial amount of oxygen
in the intake charge which is not consumed in the combustion process. This
oxygen is therefore available for the combustion of a substantial addition
of LPG resulting in a large increase in power output."
So in the case of running "HHO" into the engine you are actually putting in
a lot more oxygen than is strictly necessary and thus probably making the
engine run leaner than it otherwise would.
On 17 November 2011 16:53, Triffid Hunter <triffid.hun...@gmail.com> wrote:
> yes I've heard of many diesels using LPG as well. The idea behind this
> is that the diesel lights the LPG, so the engine uses the fairly low
> 'idle' flowrate of diesel at all speeds to replace spark plugs, and
> the LPG provides all the extra power. Since LPG is a lot cheaper, you
> get the advantages of both.
> In theory, if you replaced the glow plugs with spark plugs and fitted
> appropriate coil and distributor you could run from LPG only and still
> have the power gains from all that extra compression. Practice may be
> a little trickier!
> As for the hydrogen/oxygen thing, the energy comes from the engine. So
> the theory is more like a turbo reusing engine output to increase
> efficiency than a separate source of energy.
> I haven't seen any claims of over-unity for this particular theory
> (adding HHO gas to increase mileage) - I consider the 100%
> water-powered cars a completely separate claim, and from what I can
> tell, complete vapourware.
> On Thu, Nov 17, 2011 at 5:42 PM, Matt B <mattb.in...@gmail.com> wrote:
> > Another sort of similar system,
> > Many years (10+) ago, while working in a factory, one of the trucks we
> > loading up had an LPG tank, in place of one of the diesel tanks (LPG Tank
> > was about 1/3 the length of diesel tanks which looked around 150-200L
> > capacity each), it was a test/demo setup for an engineering company,
> > they injected a little LPG in with the air, while the diesel used normal
> > injector mechanisms.
> > The driver swore by it, he claimed it gave him more power, making uphill
> > runs faster (eg range crossings) and better mileage overall. He told us
> > refilled the LPG when filling up the other 3 tanks... So there might be
> > truth to the HHO improvements in performance, but as for overunity? the
> > is still out.. ;)
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