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but there's a catch (isn't there always) The amount of energy required to separate the hydrogen from the oxygen is quite large, generally considered more than the energy produced,

So, what if a pack of LiFeP04 batteries were fitted to provide the energy, this could be charged over night on cheap power and used to power the vehicle and the electrolyser while driving.
You were right the first time.

You will loose more than 1/2 the electrical energy converting it to hydrogen ... and you will loose more than 1/2 of hydrogen's energy burning it in the ICE to get mechanical power.

In short you are proposing a Battery to wheel efficiency of less than 25% ... this is crazy low and wasteful compared to 80% to 90% achievable with real world BEVs ... if you have the electricity ... it is more efficient to move the car with it like a BEV and skip the Hydrogen all together.

If you are not a BEV it would still be more efficient to boost the gasoline ICE with a PHEV system where the electrical energy is being used far more efficiently to provide mechanical power.

Hydrogen is cleaner ... and it is sustainable ... and it is nice for allot of things ... but it's efficiency sucks ... and it's energy per unit volume sucks.
 

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Discussion Starter · #22 ·
One thing to add to (not subtract from) T1 Terry's post.

If the heat being drawn away from the engine could heat up one surface of a TEG (Thermoelectric Generator) cell, then a lot of the wasted heat could be reverted back into electrical current. If these TEGs are coupled with a joule thief, it could draw even more thermal energy out of the steam exhaust.

I've been wanting to do this experiment with TEGs on my own car for a while.
 

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One thing to add to (not subtract from) T1 Terry's post.

If the heat being drawn away from the engine could heat up one surface of a TEG (Thermoelectric Generator) cell, then a lot of the wasted heat could be reverted back into electrical current. If these TEGs are coupled with a joule thief, it could draw even more thermal energy out of the steam exhaust.

I've been wanting to do this experiment with TEGs on my own car for a while.
If you find any TEGs in any form anywhere let me know. I would love to experiment with this technology, but cannot find any suitable information on it. Let alone parts to build one.
 

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Hydrogen is cleaner ... and it is sustainable ...
Not quite sure I would agree with it being sustainable as it depends on what the source fuel is to make the hydrogen. Other than that you summed it up pretty good.

But what is really funny, is people are easily fooled, especially if educated in the USA public education system as they fail miserably in math and science. Secondly people have no memory or desire to learn from past events. The HHO scam is old, very old and first appeared during WWII when fuel was rationed. It happened again when the in the late 70's during the oil embargo. Then popped up again in 2007/08 when oil peaked at $140 per barrel. So now here we go again with the same HHO scam with oil rising rapidly today.
 

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You will loose more than 1/2 the electrical energy converting it to hydrogen ... and you will loose more than 1/2 of hydrogen's energy burning it in the ICE to get mechanical power.
If you used an unmodified process then yes I agree, but a BEV wouldn't be much better without a lot of modification either. If the steps of weight reduction, diff ratio changes and very expensive inverter/controllers were skipped and an off the shelf 3 phase 415v motor was coupled to the standard transmission and drive system and an off the shelf commercial controller was used and conventional lead acid batteries the BEV wouldn't be a very efficient unit either, the weight along would near kill it.

If the waste heat from the exhaust was used to heat the water to produce steam and this steam was fed into the electrolyser then the need for pure water is eliminated and the electrical energy required is reduced.
An efficiently designed electrolyser using modern materials and techniques certainly wouldn't demand 500 plus amps at 96v to develop enough torque to get an ICE driving the vehicle off the mark. Keep in mind that an ICE draws in 80% anti burn material with the 20% oxygen it requires every cycle, how efficent would a small engine run with 100% combustible material at the perfect mix ratio every cycle?
If you already have the vehicle with all the required gear in there and you rip it all out and replace it with very expensive EV gear to get a range of 50km to 100km to me that doesn't sound like efficiency or financial logic, but that’s just me.
I think the hybrid drive idea is the best of both worlds, fuel the engine on LPG and a Hydrogen/oxygen mix and combine it with an electric drive motor, the huge off the mark and hill climbing amps an electric motor alone demands would be considerably reduced and a method of regen could be made to cover the times a powerpoint is not available.

T1 Terry
 

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Discussion Starter · #26 ·
Sunking, I don't think you read the OP. I was trying to start a non-scam discussion of how HHO could be integrated into a plug-in system. That, and no one here is selling anything or considering buying anything. It's ok though, that's a lot of stuff to read. Hi, I'm Taylor. I've got a degree in math, am working on a degree in EE, and I love meeting people and learning new things on forums, and I don't trust anything that says they can save me gas money by clicking on their paypal icon.
 

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One thing to add to (not subtract from) T1 Terry's post.

If the heat being drawn away from the engine could heat up one surface of a TEG (Thermoelectric Generator) cell, then a lot of the wasted heat could be reverted back into electrical current. If these TEGs are coupled with a joule thief, it could draw even more thermal energy out of the steam exhaust.

I've been wanting to do this experiment with TEGs on my own car for a while.
Had to bring this back up. Found a few web sites selling TEGs. Unfortunately the pricing is on par or more expensive than a solar panel.

Need to find out how to make one. Looks ridiculously simple. Maybe we can start an open source TEG design. The power from a standard car should be able to produce several hundred watts continuously.
 

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If the heat being drawn away from the engine could heat up one surface of a TEG (Thermoelectric Generator) cell, then a lot of the wasted heat could be reverted back into electrical current.
TE modules have extremely bad efficiency ... like ~10% efficient.

This does not boost the efficiency nearly enough ... your total net electrical input to mechanical output is still under 30%.

If these TEGs are coupled with a joule thief, it could draw even more thermal energy out of the steam exhaust.
Two corrections:

#1> Joule Thief's are not 100% efficient themselves:

Although Joule Thief's are nice in their simplicity and low cost ... they are actually very inefficient DC-DC converters ... there are many other designs that are far more efficient... more electrical energy goes input than comes output.

#2> a MPPT circuit for a TE module is more complicated than a simple joule thief.

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Not quite sure I would agree with it being sustainable as it depends on what the source fuel is to make the hydrogen.
Agreed ... although that is a question of weather the initial energy source is sustainable ... the hydrogen water chemical cycle is sustainable itself ... even if horribly low efficiency compared to other sustainable options.

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a BEV wouldn't be much better without a lot of modification either.
Even a Lead Acid Battery BEV using old school tech several decades old ... is far more energy efficient than the Water / Hydrogen cycle suggested.

the BEV wouldn't be a very efficient unit either
Even in your example ... the BEV is still far more energy efficient... and your example is far from an example of a modern BEV.

If the waste heat from the exhaust was used to heat the water to produce steam and this steam was fed into the electrolyser then the need for pure water is eliminated and the electrical energy required is reduced.


Hot water does not eliminate the chemical reasons for pure water.

The electrolysis energy is not reduced enough ...

When $10,500 electrolyzers are getting under 40% efficiency ... I seriously doubt a home made version even with exhaust gas heated water ... will still be any better than ~50% efficient ... which is still not good enough.

It still doesn't matter how efficient you got the electrolyzer ... even a magical 99% efficient electrolyzer ... is still going to be less efficient when it goes into a ~30% efficient ICE... the ICE just can not compete with the energy efficiency of a BEV system... it can compete with other things ... but not energy efficiency.

An efficiently designed electrolyser using modern materials and techniques certainly wouldn't demand 500 plus amps at 96v to develop enough torque to get an ICE driving the vehicle off the mark.


96V * 500A = 48 kw ... that defines the upper end limits of possible mechanical power ... any system using 96V and 500A has less than 48 kw of power to move with ... some will have less than others.

The highest efficiency Electrolyzer in the world ... combined with the highest efficiency ICE in the world , would produce less mechanical power to the wheels than even and average BEV using the same 96V 500Amps.

If you feel otherwise ... feel free to go build one ... I have no doubt it will work ... it will just be horribly inefficient.

Electrolyzer is way less efficient than the batteries
ICE is way less efficient than Controller + Motor combined.

how efficent would a small engine run with 100% combustible material at the perfect mix ratio every cycle?
Your ideal ICE is still less efficient than even an old school decades old Electric motor and controller combined... the very best ... multi-million dollar ICE's peak out under ideal conditions at a maximum in the low 50's for % efficiency... if you want to spend multi-millions ... the BEV is still more energy efficient.

to me that doesn't sound like efficiency or financial logic, but that’s just me.


If you want to leave the energy efficiency conversation behind and move to a vehicle life cycle energy efficiency discussion of the materials used ... that is a very different discussion ... and one where the ICE's low efficiency is still a bottle neck ... and a BEV still comes out on top.

I think the hybrid drive idea is the best of both worlds,

a method of regen could be made to cover the times a powerpoint is not available.
yes Hybrids, PHEVs, and REEVs , are all forms of improved efficiency over a standard ICE ... but are all less energy efficient than a BEV.

BEV Range is a issue ... but is another separate issue from energy efficiency... and there are a variety of solutions for BEV range issues as well.
 
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