# Hydrogen & EV hybrid theroy



## mr9802 (Feb 26, 2015)

So I have a question about dual power(hydrogen and batteries) in an electric car. My question is not how to convert hydrogen to electricity, it is more on the controller side. Much like the Toyota Mirai claims to use the Hydrogen fuel cell for normal power operations but will also be available to use the battery pack when needing a higher demand of current.

So long story short, if you had a Fuel cell power with a BMS & an controller (like a curtis), could the motor controller use the fuel cell for most of its operations and charge the batteries when the batteries are not being used?

I have tried to do research with range extenders but feel this does not fit the typical "generator" application. Any suggestions if this would work?


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## Tomdb (Jan 28, 2013)

most fuel cells are used with a dc/dc between to get the correct voltage. 

I believe the fuel cells are connected to the batteries, then the batteries to the inverter and motor. This way the battery just acts like a huge capacitor. I dont know what kind of "target" voltage they would modulate the conversion dc-dc to.


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## Tesseract (Sep 27, 2008)

Off topic for this forum, but generally speaking, fuel cells like loads that are constant or only slowly changing. Consistent with that, they also generally hate a lot of reflected ripple, so you wouldn't want to directly feed either a DC or AC motor controller with one, either.

So the ideal setup for a fuel cell EV is to have it feed a boost converter that acts as a charger for a battery bank which then feeds the motor controller. You can minimize the size of the battery bank by only requiring it to provide peak power to the controller (which necessitates a higher power fuel cell) or you can size it to deliver both the peak power and as much independent range as desired/possible, with the fuel cell sized to only supply the average consumption at, say, 60mph on flat road (typically 10-20kW).

Either way, it's going to a very expensive solution, hence why no one else has documented one here.


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## Sunking (Aug 10, 2009)

Hydrogen economy is a false economy and will never work. It is a huge strain on resources.

Hydrogen is not a fuel source, it is a carrier of energy and a very poor one at that. As any carrier of energy mean sit has an EROI of less than 1. That means it will always be a multiple price of the source fuel used to make it. 

Cradle to grave deficiency of hydrogen is on the order of 5 to 10% by the time you account for the source fuel to make it, leakage, thermal losses, cryogenic refrigeration, and transportation cost by rail or truck. That means you burn 10 to 20 units of energy to make 1 unit of energy.

That adds up to STUPID waste of resources. It would be a great investment scam. Today you give me $20, and tomorrow i pay you back $1.


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## mr9802 (Feb 26, 2015)

Thank you all for the quick replies!

My concern at this point is not related to costs but has me thinking of theory and principles. 

If you had a FC you would need a do/doc converter to supply the batteries with the voltage for your setup? 48, 72, or whatever your setup is correct? Then you would need another after the batteries and before the motor controller? This where I get lost. Or would a good bms setup help not put a strain on the batteries?

Btw the setup would be for an ac motor like the ac50 with a Curtis controller plus the extra can bus adapter for other controls via can bus.


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## Tomdb (Jan 28, 2013)

one High voltage/Highpower DC/DC

FuelCell->DC/DC->Batteries->Controller

Batteries don't need to be too controlled, except for top and bottom voltages with a " BMS" . The batteries are quite self regulating if your DC/DC has a good voltage regulation based on the input power from the Fuelcell.


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## Moltenmetal (Mar 20, 2014)

Fuelcells are expensive and designing one to run like an IC engine, sized for the peak power the vehicle needs, would be nuts- so a hybrid solution like this is the only option. There are problems there, but they're easily if not cheaply solved with electronics. But the problems of hydrogen, including the energy inefficiency of the production/storage/delivery cycle, are not going to be overcome- they're problems related to fundamental properties of hydrogen.


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## RIPPERTON (Jan 26, 2010)

A more economical use of Hydrogen would be HHO generation through electrolysis as a feasible range extender for an ICE vehicle and thus be a PHEV.
Using an 80v lithium battery pack recharged from AC mains in total loss ie not recharging from the ICE alternator and a simple 100A DC mosfet controller as a pulsed supply for the HHO generator.
I am working on such a system atm but all the 316 stainless plates will be expensive.
The higher combustion temperatures of a HHO flame would probably melt a piston if used without unleaded fuel so HHO could only be used as an additive.


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## samwichse (Jan 28, 2012)

Why would you want to get 50% of your battery energy in hydrogen from electrolysis and then feed that into a 20% efficient IC engine? That doesn't sound very economical...


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## Moltenmetal (Mar 20, 2014)

Given that air comes to your IC engine for a very little horsepower merely to draw it in, and there is virtually no unburned fuel in your exhaust, I'm puzzled what additional efficiency people think they're going to get when they put Brown's gas (stoichiometric hydrogen and oxygen from electrolysis of water) into their engines. Yes it will raise combustion temp a bit (not enough to usefully improve efficiency or enough to damage your engine, take your pick) and it will probably phreak your O2 sensor and increase your emissions, , but not much else.


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## RIPPERTON (Jan 26, 2010)

From the 7kWh ($1.90) in your 80v pack you might get 300km range extension.
300km for $1.90........ am I talking too fast.
You have to do this with a carby engine or an old diesel because yes the O2 sensors will "freak out"


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## Duncan (Dec 8, 2008)

RIPPERTON said:


> From the 7kWh ($1.90) in your 80v pack you might get 300km range extension.
> 300km for $1.90........ am I talking too fast.
> You have to do this with a carby engine or an old diesel because yes the O2 sensors will "freak out"


And if you send me $1000 I will tell you exactly how to do it

PS - I have several bridges for sale if you are interested


Come on Ripperton the old H2 O2 scam has been ripped to threads long ago


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## RIPPERTON (Jan 26, 2010)

Duncan said:


> Come on Ripperton the old H2 O2 scam has been ripped to threads long ago


Im not selling you anything !!


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## Sunking (Aug 10, 2009)

RIPPERTON said:


> A more economical use of Hydrogen would be HHO generation through electrolysis as a feasible range extender for an ICE vehicle and thus be a PHEV.


OMG another moron who believes in HHO. Please do not vote in any elections or have children.


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## RIPPERTON (Jan 26, 2010)

Sunking said:


> OMG another moron who believes in HHO. Please do not vote in any elections or have children.


OMG another common TROLL who believes in insults.


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## Sunking (Aug 10, 2009)

RIPPERTON said:


> A more economical use of Hydrogen would be HHO generation through electrolysis as a feasible range extender for an ICE vehicle and thus be a PHEV.


Pixie Dust

https://www.youtube.com/watch?v=Kv9vMzXJbho


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## RIPPERTON (Jan 26, 2010)

Sunking said:


> Pixie Dust
> 
> https://www.youtube.com/watch?v=Kv9vMzXJbho


The test car (Honda) they used was fuel injected and obviously had an oxygen sensor which after a while teaches its ECU to adapt to and nullify the presence of HHO.
That's why I said it only works on carby engines.


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## Duncan (Dec 8, 2008)

Ripperton
Why would you expect any improvement by adding H2 O2 gas?
You are not going to improve "combustion" when it's already 99.9%

Why would you expect any improvement?

There are simply not any significant inefficiencies present 
Certainly nothing like enough to warrant the overall 10% (if that) efficiency of producing the stuff


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## Sunking (Aug 10, 2009)

RIPPERTON said:


> The test car (Honda) they used was fuel injected and obviously had an oxygen sensor which after a while teaches its ECU to adapt to and nullify the presence of HHO.
> That's why I said it only works on carby engines.


What are you smoking?


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## RIPPERTON (Jan 26, 2010)

Duncan said:


> Ripperton
> Why would you expect any improvement by adding H2 O2 gas?
> You are not going to improve "combustion" when it's already 99.9%
> Why would you expect any improvement?


A its the cost of making the HHO, its a lot cheaper that ULP and 
B its the fact that its already a gas that makes it better for combustion.

Even EFI engines admit liquid fuel into the engine and it takes time to convert all of the liquid into a burnable gas.
Yes you are burning all the fuel but half of it gets burnt after the exhaust valve has opened because at the ideal time of combustion (just after TDC) it wasn't ready to be burnt ie it was still a liquid and as any TROLL knows you cant burn liquid fuel, only gaseous fuel burns.
The atomised liquid fuel droplets start to produce a cloud of vaporised fuel around them as they enter the hot inlet port of the cylinder head and continue to do so way out the other side of the head in the exhaust port, the entire time shedding off its liquid properties and giving off vapour to be burnt with the dwindling amount of oxygen that was always diluted by massive amounts of inert Nitrogen. Hence the reason for air injection, there is so much excess fuel admitted into the engine that by the time its in the exhaust manifold they have to give it some more air to complete the burn properly.
So at the crucial phase of combustion ie from TDC when the spark plug fires to about 120 degrees later when the exhaust valve opens, you have your combustion chamber more than half full of completely useless bullshit ie unburnable liquid fuel and nitrogen.
Now lets look at HHO you have 2 molecules of gaseous fuel all ready to burn, no preparation needed and you have a giant molecule of pure oxygen offering stoichiometric awesomeness, born to burn.
So what HHO does is it substitutes low performance AIR FUEL for high performance HHO.
About that bridge you were talking about earlier, why don't you go hide under it with your dirty keyboard now that youve had your ass handed to you by a Master Mechanic.


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## jonescg (Nov 3, 2010)

Easy Dan - just build a working prototype and run the numbers on it. Calculate the kWh required to make a couple of moles of hydrogen and oxygen gas. Then feed this gas into the intake. Not sure whether you plan on feeding all of it, in place of the throttle body, or just some of it. But if you are feeding all of it in, you will need more than a few moles. More like a hundred litres of pressurised, stoichiometric H2+O2. Then determine your power levels and fuel economy.

If it's bunk, the numbers will show. If it works, you will be getting the last laugh. As it's already an explosive mixture, I would be very wary of storing it onboard. The fuel in a tank doesn't explode when the cap is set on fire because there's no O2 in there for it to burn. But a tank of HHO would be spectacular.

I'm sceptical that burning it directly, or in an ICE, is good use of resources. But I'll happily be proven otherwise.


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## RIPPERTON (Jan 26, 2010)

Theres no tank and its only just enough pressure to make it move down the tube that goes from the generator to the upstream side of the throttle body. Theres less than a liter of HHO in the tube and theres a shutoff valve that stops the flow of HHO at engine idle and a 0.3 bar pressure switch that shuts the system off.
I don't think you could run an ICE purely on HHO because of combustion temps are too high.
Sure it all comes down to how many km's worth of range extension you get from a 7kWh pack but at $1.90 its worth the expense and time to find out.

To Sunking and Duncan, this is the kind of discussion we are use to on this forum.


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## onegreenev (May 18, 2012)

Just run your HHO for 5 minutes on your full 7kWh pack and capture the amount of gas for 5 minutes. Then just let it go and continue to produce until the battery is depleted. Then calculate how much gas over time and see if the amount is going to be enough and if you can get enough extra distance to warrant using such a system on your vehicle. Its pretty much been bunked out but I have seen a small lawn mower engine running straight HHO gas. The biggest issue is quantity of gas fast enough. Even for a benefit it will be pretty doubtful you can attain a good enough output on demand. Ive heard all sorts of claims. If anyone has a good HHO I will do a test for you if you want to send the unit my way. I have plenty of kWh of battery to give a good test. 

I don't plan on ever building an HHO machine myself.


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## Sunking (Aug 10, 2009)

jonescg said:


> Easy Dan - just build a working prototype and run the numbers on it.


He cannot do it. No one can. There are a bunch of scientific organizations out there with huge rewards for the first person to produce a working prototype. They have been waiting since WW-II when the SCAM first appeared during fuel rationing. It appeared again in the 70's during the oil embargo, both at that time vehicles used carburetors. The SCAM appeared again in late 2000's when gas prices shot up again. 

The SCAM just keeps repeating itself with a different more clever approach to dupe the desperate public. If it really worked, that person would be the next Bill Gates. But as it turns out all those that have tried proved to be just another Peter Jenning trying to con the public.


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## Duncan (Dec 8, 2008)

RIPPERTON said:


> A its the cost of making the HHO, its a lot cheaper that ULP and
> B its the fact that its already a gas that makes it better for combustion.
> 
> Even EFI engines admit liquid fuel into the engine and it takes time to convert all of the liquid into a burnable gas.
> ...


As an engineer with over 20 years of experience in automotive engineering,
(Mostly on the combustion/fuel system side)
I have to say that that is total nonsense

I meet your "Master Mechanic" and raise you one Professional Engineer


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## Moltenmetal (Mar 20, 2014)

Sorry, but that's complete bovine effluent. You are really theorizing that the fuel fed to the engine is burned at the wrong time or is incompletely combusted, both of which are demonstrably false claims. The one can be proven by, say, putting the engine on a dyno and recording power output versus RPM, or by fuelling an engine with propane or natural gas or hydrogen for that matter, and the other by analyzing the exhaust ( which is done frequently as an emissions test). So there- to use your rude parlance, your own @ss has been handed to you by an engineer, Mr. Master Mechanic! I don't doubt your skill in your trade, but your knowledge about the thermo behind the heat engines you work on could use a little brushing up I'd say!

Electrolysis uses electricity- work on tap, the highest value form of energy, which can readily be converted to work with high efficiency- to produce fuel and oxygen from its full combustion product (water) at a very steep energetic penalty. The only way feeding it to an engine can improve efficiency is if it also illegally affects combustion emissions of that engine. You can achieve the same results with a variety of mods to an engine, all of which also increase emissions.


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## RIPPERTON (Jan 26, 2010)

Duncan said:


> I have to say that that is total nonsense
> I meet your "Master Mechanic" and raise you one Professional Engineer


ok Mr Pro Engineer, give us a detailed explanation of how a turbo charger works, and this is very relevant to the topic.
And you say that my detailed account is total nonsense but you don't have the expertise to say why. Elaborate.
I keep coming to the same conclusion that Engineers are mostly educated beyond their intelligence


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## RIPPERTON (Jan 26, 2010)

Moltenmetal said:


> You are really theorizing that the fuel fed to the engine is burned at the wrong time or is incompletely combusted, both of which are demonstrably false claims.


I think your comprehension is demonstrably false.
I said nothing of the sort so I will ask you to go back and read it again.
What I said was that fuel was burnt at all times both right and wrong and I actually said that combustion was complete.


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## RIPPERTON (Jan 26, 2010)

onegreenev said:


> I have seen a small lawn mower engine running straight HHO gas.


It may have been running at idle or light load ie small volumes of HHO mean relatively low combustion temp. Give it full throttle with load and temps will soar.


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## Duncan (Dec 8, 2008)

RIPPERTON said:


> ok Mr Pro Engineer, give us a detailed explanation of how a turbo charger works, and this is very relevant to the topic.


What part of it do you want to know?
Compressor maps?
Turbine maps?
Variable geometry?
Waste-gates?
Effects of pulse dynamics?
Effects of blade curvature?
Effects of whirl in the bearings?

I would have to look up some of my old stuff - I suspect its all public domain by now

So what do you want to know about


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## RIPPERTON (Jan 26, 2010)

Duncan said:


> What part of it do you want to know?
> Compressor maps?
> Turbine maps?
> Variable geometry?
> ...


A simple physical explanation ie where does the power come from to create the X bar of boost pressure


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## Duncan (Dec 8, 2008)

RIPPERTON said:


> A simple physical explanation ie where does the power come from to create the X bar of boost pressure


Depends on the turbocharger setup
Anything between 30% mass flow rate and 70% pulse and 80% mass flow rate and 20% pulse

Thinking about what you have said
You think that the H2 O2 is speeding up the combustion front?

Well you are wrong - 
Which is just as well or you would have uncontrollable pre-combustion (Knock)

NOT a desirable outcome - so its just as well it doesn't happen


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## RIPPERTON (Jan 26, 2010)

Duncan said:


> Depends on the turbocharger setup
> Anything between 30% mass flow rate and 70% pulse and 80% mass flow rate and 20% pulse
> Thinking about what you have said
> You think that the H2 O2 is speeding up the combustion front?
> ...


Sorry mate that doesn't satisfy my understanding of how a turbocharger works.
Il give you another chance. Il ask the same question again you know like once more for the dummies.
Where does the power come from to create the X amount of boost pressure.
You don't have to get specific all turbos work on the same principle.
Now what you did in your last post was negate the question by changing the subject which obviously means you cant answer the question so you don't know how a turbo charger works.
You do realise that even if you do answer the question correctly you will contradict what you said in post 25 which means you will have had your ass handed to you twice in one day by the same person.
This is fun
They should make TROLL Bashing an Olympic sport


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## Duncan (Dec 8, 2008)

Ripperton
You are obviously angling for the answer that it is the excessive energy in the exhaust gasses that is used to drive the turbine
This in NO WAY helps your argument
You will always have excessive energy in the exhaust

You still seem to think that an IC engine is some stone age undeveloped device
You are wrong!
A modern IC engine is a well developed machine that harvests almost all of the available energy
(notice I said "available") 
and is running close to 90% of theoretical (heat engine) max efficiency
There is NO extra energy available by making the gases burn faster
(Which you can't anyway)

I'm sorry if this is too technical for a mechanic but that's thermodynamics

After you have done a little homework you could come back and apologize


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## RIPPERTON (Jan 26, 2010)

Duncan said:


> Ripperton
> You are obviously angling for the answer that it is the excessive energy in the exhaust gasses that is used to drive the turbine
> This in NO WAY helps your argument
> You will always have excessive energy in the exhaust


You really are unbelievable Drunken I mean Dunken.
Yes wasted combustion that ends up in the exhaust because the Air Fuel burn time is always longer than the power stroke phase.
And just as I predicted you have contradicted yourself now because of your simple minded response to my post #20 you blanket trashed everything I said in it including specifically that part that said combustion in the exhaust so now you are proven to be a Troll and I will hand your ass to you once again...No wait, Im sophisticated TROLL BASHER Ima FedEx your ass to your ex wife so she gets a laugh out of it too.


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## RIPPERTON (Jan 26, 2010)

Duncan said:


> You still seem to think that an IC engine is some stone age undeveloped device
> You are wrong!


Of course External Combustion Engines are undeveloped stone age crap, what do you think we are doing in here developing more sustainable electric technology. Or more to the point what are you doing in here if you love ICE's so much ??
Maybe your in the wrong place Doonkan you like having your ass kicked so much why don't your find some gay forums.
And if you don't like my bashing maybe you shouldn't have attacked me in the first place with your TROLL diatribe.
Really theres nothing wrong with constructive argument


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## RIPPERTON (Jan 26, 2010)

Duncan said:


> A modern IC engine is a well developed machine that harvests almost all of the available energy
> (notice I said "available")
> and is running close to 90% of theoretical (heat engine) max efficiency
> There is NO extra energy available by making the gases burn faster
> (Which you can't anyway)


ICE have never been better than 30% efficient and if you don't know this you are obviously not an engineer. Available energy means all that which is in the fuel to start with.
Plus we don't need extra energy, we just need less fuel to make the same energy, by having a fuel that ignites easier burns faster we can chronologically match the combustion cycle time and have no spill into the exhaust.
So like I said before, educated beyond your intelligence.


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## Duncan (Dec 8, 2008)

Ripperton you are an idiot
IC engines are 90% of theoretical max efficiency - which ends up about 35% overall

Only a "mechanic" with no engineering or thermodynamic knowledge at all would believe the sort of crap you obviously do


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## Duncan (Dec 8, 2008)

Ripperton
As somebody who obviously needs a physical example 

Look up the overall efficiencies of IC engines using natural gas (methane - no droplets!)
and hydrogen (even less droplets) 

Look at turbocharged! natural gas engines!

The fuel is already a vapor
What difference does it make to the efficiencies? - Damn all 
And if you want you can put your hand in front of the exhausts of such engines - it will get burnt - but I'm sure that's all in the mind

Then after reading a couple of thermodynamics textbooks come back and bring me a definition of entropy and an example of an is-entropic process


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## RIPPERTON (Jan 26, 2010)

Duncan said:


> Ripperton you are an idiot
> IC engines are 90% of theoretical max efficiency - which ends up about 35% overall


Why do you even bother saying 90% "theoretical" then you go and correct yourself and repeat what I said 30%. The 90% means shit.
Why do you need to be rude and aggressive and virtually violent in a forum where a civilised conversation will do. So I have a few theories and Im not even trying to sell anybody anything or rip anyone off yet you need to act like an asshole and attract the attention of admin. So what if Im wrong in the end, your behaviour is out of line.


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## RIPPERTON (Jan 26, 2010)

Duncan said:


> Ripperton
> As somebody who obviously needs a physical example
> Look up the overall efficiencies of IC engines using natural gas (methane - no droplets!)
> and hydrogen (even less droplets)
> ...


Methane and straight Hydrogen ? burnt with what? air ? which is 80% nitrogen I spose that wouldn't have any effect on combustion compared to pure oxygen.
My god you are a bit backward if you think that you can recommend reading thermodynamics books to a member of an electric vehicle forum.
Mate you really are in the wrong place.


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## Duncan (Dec 8, 2008)

Ripperton

I made a mild joke about selling bridges when you seemed to believe in a well known scam

You were the one who escalated it and called me a troll!
And you are still doing it calling me an asshole!

As far as "attracting the attention of the admin" 
You are joking ?


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## Duncan (Dec 8, 2008)

And just because this is an EV forum the laws of thermodynamics have somehow been overthrown
What about the gravity?
Strength of materials?
Are all of these irrelevant because this is an EV forum??


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## jonescg (Nov 3, 2010)

Dan - quit the snark and build your HHO-assisted ICE engine. That will put it to rest. If you cannot succeed in making your ICE engine run better/faster/more efficient with the hydrogen input, then so be it; the others were justifiably right to be sceptical.

I am a scientist, so I shan't declare a 'side'. However the laws of thermodynamics are awfully hard to defy...


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## Tomdb (Jan 28, 2013)

I have done some research, with actual testing, during my education.

We had a engine running on straight up hydrogen, a mix and one with hydrogen combined with CNG.

I have found that mixing hydrogen does increase the flame propagation, thus requiring a later ignition timing. However with a too large volume of hydrogen under heavy loads it takes next to nothing to set off the detonation.

Mixing in hydrogen will allow for a very and i mean VERY lean combustion cycle going very lean will allow you to gain some efficiency, how ever this is always a small step. 

On the engine efficiency part, there are diesels that can run above 35% efficient.

PS. guys please keep the bashing of other to a minimum, for some reason the past week this has been a grow trend.


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## Moltenmetal (Mar 20, 2014)

Let's break it down for Ripperton a bit, in the hope he calms down and listens to reason.

The way to think of a heat engine is as a waterwheel which extracts work from heat as it falls in the normal direction- the one it travels in spontaneously- which is from hot to cold. Want to move heat from cold to hot? You can- by doing work to run a heat pump. Heat engines have a theoretical maximum efficiency for making work (mechanical energy) out of heat, which is related to two things- the temperature of the "hot reservoir" (in this case, the temperature of the hot gas generated by burning the fuel) and the temperature of the cold reservoir- the place the heat is rejected to, ie ambient temperature. An IC engine already has the hot reservoir about as hot as a) the materials can stand and b) the temperature at which oxygen combines with nitrogen in the engine rapidly to make oxides of nitrogen, which are harmful in themselves and also help to make ground level ozone- very bad for human health.

That Carnot theoretical max efficiency is around 35% for the respective hot and cold temps in an IC engine. Real IC engines get pretty close- from 15 to 30%. Most of the unharvested energy that is still available for extraction in the form of work is in the exhaust in the form of pressure and heat, and on large engines the heat from the exhaust is used to preheat the combustion air- a small gain for a large, expensive exchanger, but one which pays back for a stationary power plant.

The remaining energy- the 65 % of the chemical energy in the fuel that you were unable to covert to work- isn't available to convert to work with a better heat engine, or with a heat engine running on the exhaust. However, the remaining heat is available to use as comfort heating etc in a combined heat and power "cogen " scheme.

Efficiency is different than power. There are many things that you can do to make more power from an engine of a given size by increasing how quickly you can feed fuel and air to the engine, but some of these will actually reduce efficiency.

Feeding oxygen and hydrogen instead of or in addition to fuel and air will increase combustion temperature and hence increase efficiency. But increase that more than a little above what the current engine does and you'll either start melting stuff in the engine or causing it to fail prematurely, or you'll be making lots of NOx, or both. The only way you can get the efficiency gain even if you don't care about emissions is to either not have an O2 sensor or other emissions controls or to deceive it.

The the energy to make that hydrogen and oxygen has to come from somewhere, and the electrolysis process is also inefficient- it requires electricity which is work, not heat or chemical energy, and converts it to LESS chemical energy. Even if that process were 100% efficient- and it isn't and can't be made so for other demonstrable reasons- you would be losing- wasting a resource. We might measure heat and work in the same energy units- joules or kWH - but heat and work or electricity are NOT the same in terms of energy available to do work. A process which converts work to heat with 100% efficiency isn't magic either- an electric heater does that- and it's a waste of work too. If you used that same amount of electricity to run a heat engine such as a heat pump instead, you could move 3.5 watts of heat from a cold place to a warm place for every watt of electricity you used!

You can use that oxygen and hydrogen in a fuelcell, which because it is not a heat engine does not suffer from the Carnot efficiency limit. However, best available technology right now in fuelcells is only going to get you about 60% of the source electricity back again once all the fuelcell's needs are met. And unlike pure hydrogen, you cannot safely compress a mixture of hydrogen and oxygen to store it because it will spontaneously ignite. Once you add in the terrible inefficiency of compressing hydrogen to very high pressures to store it, and purely wasting that pressure potential energy again when you expand it to use it in the fuelcell, your overall process efficiency is not even as good as you get out of an IC engine.


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## Sunking (Aug 10, 2009)

RIPPERTON said:


> Why do you even bother saying 90% "theoretical" then you go and correct yourself and repeat what I said 30%.


Dude you are one stupid Grease Monkey of a Mechanic.


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## RIPPERTON (Jan 26, 2010)

Tomdb said:


> PS. guys please keep the bashing of other to a minimum.


Il try but they make it so easy and I just cant resist the temptation


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## RIPPERTON (Jan 26, 2010)

Sunking said:


> Dude you are one stupid Grease Monkey of a Mechanic.


The only reason I havnt ripped you to pieces like Dumcan is because Im kind to retarded people.


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## aeroscott (Jan 5, 2008)

Tomdb said:


> I have done some research, with actual testing, during my education.
> 
> We had a engine running on straight up hydrogen, a mix and one with hydrogen combined with CNG.
> 
> ...


What kind of efficiency did you get on h2 and on blends of h2 and other fuels. 
My understanding is any engine run on h2 gets a large increase in efficiency , up to about 40 percent .


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## Tomdb (Jan 28, 2013)

I was just collecting data and running tests. 
The main issue we had with the pure hydrogen combustion was premature detonation. This is was caused by the low ignition energy of a hydrogen mixture. This caused allot of backfires. I personally taught the project was flawed as the hydrogen injection was done in the intake not in the cylinder. 

http://www.greencarcongress.com/2006/09/the_arguments_f.html

good comparison article

http://www.yale.edu/gillingham/hydrogenICE.pdf

a nicely worded paper that discusses the topic well.


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## Duncan (Dec 8, 2008)

Tomdb said:


> I have done some research, with actual testing, during my education.
> 
> We had a engine running on straight up hydrogen, a mix and one with hydrogen combined with CNG.
> 
> ...


Hi Tom
Excellent post
The only trouble is your _VERY lean combustion_ will blow away your NOX limits
We can achieve very lean combustion without the H2O2 - things like stratified charge

Modern engines are very well optimized - there is no "low hanging fruit

A comment on your experiment
If you were comparing an engine with H2O2 added and without you should optimize both engines when doing the comparison
You would also need a suitable sample size
When I used to do this type of thing we would use 30+ individual engines

All that the optimization on modern engines is on the "recipe" 
individual engines are not optimized in production

This means that if you made a small change in an engine(for instance drilled a 3mm in your intake manifold) you would see some of the individual engines move closer to the optimum and some of them move away from optimum 

These changes will be tiny and difficult to measure repeatably 
(which is another reason why we use larger sample sizes when developing the recipe) 

Hi Aeroscott
No you are NOT going to see a 40% improvement in efficiency
As Moltenmetal said the absolute maximum efficiency that the gods of thermodynamics allow is about 35% (a bit more for diesels) and we are aproaching 90% of that which gives 31%

So there is maybe 5% available if you could make a "perfect" engine

The combustion engineers I worked with would happily sell their grandmothers for a 1% efficiency boost

This is talking about modern fully optimized engines 
If you have some weird home made device or bitsa you could well have much lower efficiencies
If you have something that is a real dog then making it run properly could be 40% better!


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## RIPPERTON (Jan 26, 2010)

Duncan said:


> Ripperton
> 
> I made a mild joke about selling bridges when you seemed to believe in a well known scam
> You were the one who escalated it and called me a troll!
> And you are still doing it calling me an asshole!


Well at least you admit to being guilty.
Your mistake is responding aggressively to my believing in a "so called" scam. I can believe in what ever I want and wether its right or wrong you don't have the right to flame me full stop. You deserve everything you got from me because you were way out of line and you still are.
Maybe in the future you will be more wary of landmine personalities like me and keep your vulgar behaviour to yourself.
Your unrelenting aggression leads me to believe you are pushing some kind of agenda and only makes me more sure that HHO does work.
Otherwise it would be just science and no need for aggro, right ?


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## RIPPERTON (Jan 26, 2010)

Duncan don't get so worked up when You get bashed mate, its just the internet...
http://www.liveleak.com/view?i=10b_1425307637


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## Duncan (Dec 8, 2008)

RIPPERTON said:


> Duncan don't get so worked up when You get bashed mate, its just the internet...
> http://www.liveleak.com/view?i=10b_1425307637


Peace - I do like your motorbike threads and I will be re-reading them when I get permission (from the wife) to build a motorbike


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## Moltenmetal (Mar 20, 2014)

Ripperton- you are free to believe what you want, just as we're free to challenge your "belief" with what we know. And don't worry- you may have a landmine personality as you said, but most of us here have a pretty thick skin. When I responded to your comment, I took the lead from your response to Duncan. 

In the end we're interested in many of the same things here, and have lots to learn from one another. But there are a few immutables like thermodynamics, conservation of energy etc. that you don't step across without getting blasted- and so it should be. Enough human effort has been wasted already trying to violate these rather obvious rules of the universe we live in.


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