Like many people I am very interested in gadgets meant to save fuel. I recently started looking at the devices which convert water to hydrogen and oxygen which then feed this mix into the car air intake. The idea is that the hydrogen and oxygen mix burns in the engine and reduces the need for petrol/diesel.

The suppliers of these HHO devices, as they are called, claim 10% to 60% fuel reduction. There are loads of videos about them on and plenty of suppliers offering them on the web and some via ebay.

I was getting rather excited by all this and was thinking of buying one, but some nagging doubts held me back. I looked around for some independent reviews and could not find much.

One of the few tests I found was Popular Mechanics
Water-Powered Cars: Hydrogen Electrolyzer Mod Can’t Up MPGs

This test showed no improvement in fuel consumption from using an HHO device, but the test has been criticised by some commentators (see comments at bottom of the above article) for making some basic mistakes (ie HHO devices often need a chip to link to the fuel management system and the test did not include one, etc.).

At the extreme there is one guy actively working to “debunk” the whole thing. He is not at all impressed by  the anecdotal evidence of people claiming to have fuel efficiency improvements from these devices. His article and the comments/responses are very interesting and entertaining.

Run your car on water? Nonsense! It is a Scam!

I think the same guy is also here: The Hydrocharger, HHO scammers in the UK – again with some interesting and rather intense interactions going on in the comments section.

The whole HHO car kit arena has claims, counter claims, and counter claims to the counter claims. The sceptics claim it is all bad science as it takes more energy to separate the water into hydrogen and oxygen than can possibly be got from the combustion reaction from them; the supporters claim that the hydrogen makes the combustion more efficient and that’s where the fuel economy comes from. The sceptics claim lack of verifiable independent evidence, the supporters claim the government, and oil companies etc., are against them. And so it goes on… and on….

Within all this there is something that stands out to my mind: there is no established ecological group encouraging us to adopt the HHO car device technology. They have no vested interest in the status quo. They stood up for wind power, solar fuel cells and so on, long before these became accepted as the norm. They have resources to test such things 0r access to those in universities etc., who have. Yet despite the significant fuel saving and pollution reduction claimed by these HHO devices no well-known ecological group has stood up and supported them. That makes me wonder. Measuring fuel consumption is hardly rocket science (pardon the pun)  – how hard can it be to really prove these things work?

Failing the eco groups supporting it why don’t the suppliers of these HHO gadgets get a university to do some tests (club together if they have to)?

I am not sure what to make of all those who claim to have had huge improvements in fuel consumption from these devices. The sceptics claim such people are either have a vested interest in selling the devices, or are just fooling themselves as fuel consumption varies a lot anyway. The latter can be easy to do.  I remember years ago I worked with a guy who loved to joke about how much better his car performed right after he washed it. I’ve noticed my car does that too!

I have not offered any links to sellers of these devices as they can easily be found by a search such as ‘hho car kit’ and the like. You can easily see all the ‘pro’ arguments that way.

It would be wonderful if such things worked, but I have gone from hopeful to wary. There seems to be some very genuine and intense people on both sides of the argument (as well as vested interests on both sides). However,  I have not find what I was looking for which was genuine reviews that compared the different HHO gadgets and their actual fuel saving – after all this would be normal for a consumer device – so I’m holding off buying one. Once I see independent, test, study or reviews (especially a consumer comparison review) by a reputable organisation then I would really know they are for real.


I should mention that when I checked for providers of HHO systems in UK the main one I found gives no address on their website. The site says ‘based in London’ in various places and the Google map seems to point to a flat or house – but that’s it. Considering that they are selling some fairly high priced units, that makes me wonder what is going on.