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Old 02-11-2012, 10:28 AM   #130 (permalink)
IamIan
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Quote:
Originally Posted by Ken Fry View Post
For an HHO unit to "work" to improve fuel efficiency, the electrolysis process would have to operate at greater than 500% efficiency.
It isn't quiet that bad ... especially from a 'energy I pay for' perspective.

From a Energy balance point of view to break even ... I think the current technological lower limit would be around ~138% efficient electrolysis ... and ~276% from what I've seen in things automotive size... As an absolute limit , I think the combined steps from chemical energy to electrical energy back to chemical energy would have to reach ~83% Efficient ... not currently possible that I know of.

I know some HHO advocates like to try and claim the energy lost in getting the hydrogen can be made up in the efficiency benefits of Lean burn ... by using the faster flame speed of hydrogen to support lean burn in an engine not designed for it ... but as the study referenced earlier in this thread showed ... even without paying for the energy costs of getting the hydrogen ... the net ICE efficiency benefits from were about ~3.8% when they were using ~1.5Lb/hr of Hydrogen.

Engines designed for Lean Burn have been tested to operate at up to ~20% more efficient ... and they do it without the additional weight of the HHO system , or the energy losses of getting the hydrogen from water.

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HHO not to be confused with Hydrogen (H2) as an energy carried and water (H2O) used in a combined cycle type system ... which would still have the efficiency issues of getting the H2 from some other energy source.
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