Thread: Hydrogen Fuel
View Single Post
  #27 (permalink)  
Old 21st July 2008, 07:40 AM
JDNSW's Avatar
JDNSW JDNSW is offline
ForumSage
Subscriber
 
Join Date: Jan 1970
Location: Central West NSW
Posts: 6,696
Thanks: 162
Thanked 414 Times in 375 Posts
Quote:
Originally Posted by Michael2 View Post
I saw a video on the www a couple of years ago, but haven't been able to find it since.

There was a small motor (lawn mower motor I think) that was powered by hydrogen gas. The motor drove an alternator which powered a small welder and it turned an aluminium drum. The drum was submerged in a tank of water and the welder electrode touched the aluminium drum and arced. The spinning drum stopped the electrode from sticking to the aluminium. The arc bound O2 to the aluminium, falling to the bottom of the tank as an aluminium oxide residue, and the liberated hydrogen bubbled to the top and powered the motor.

Was it real? I don't know.
Was it real? Depends what you call real. But unless the inventor has found a way to repeal the law of conservation of mass-energy, then the engine was not running solely on the hydrogen produced.

Consider these facts:- Best energy efficiency of any internal combustion engine is about 40%, but no small engine such as described will do much better than 20%. Alternator energy efficiency is around 80%, and electrolysis efficiency around 80% at best.

So the overall energy loss in the closed cycle described is around 87%, which means that running the engine on the gas produced is simply impossible.

Use of hydrogen gas produced on board by electrolysis has the potential to improve combustion, and hence energy efficiency, showing up as increased fuel economy or power, along the same lines as gas injection. However, gas injection uses far more gas than can be produced from the total output of any standard alternator, so until I see properly documented, peer reviewed testing, I will remain sceptical.

This should not stop anyone who wants to try it, but don't expect any spectacular results, and beware of self-deception.

John
__________________
JDNSW
1986 110 County 3.9 diesel
1970 2a 109 2.25 petrol
Reply With Quote
The Following User Says Thank You to JDNSW For This Useful Post:
drivesafe (21st July 2008)