Hydrogen Internal Combustion

[benjamindees]

Article on using direct injection diesel engines with hydrogen fuel:

http://www.osti.gov/energycitations/product.biblio.jsp?osti_id=82437

From a little googling, some of the problems with running an engine on hydrogen are pre-detonation, lack of lubrication, and nitric oxide emissions.

This story has info on the modifications BMW made to its hydrogen engine:

http://www.prnewswire.com/cgi-bin/stories.pl?ACCT=109&STORY=/www/story/09-20-2004/0002253879&



;EDATE=

Pre-detonation can supposedly be cured by a Wankel rotary design.  

Lubrication can be aided by injecting water along with hydrogen.

And here's a place that sells Ford engines that run on hydrogen:  

http://www.hydrogenenginecenter.com/

[electrondady1]

very informative, thanks for the links.things are changing quickly,i never thought i'd see hydrogen ready engines being marketed!

[Ungrounded Lightning Rod]

Running an internal combustion engine on electrically-produced hydrogen is horribly inefficient.  (It's like running an absorbtion-cycle refrigerator on an electric heater, for the same reason.)

You have to make the hydrogen - typically by first making electricity then electrolyzing water.  Having taken that high-quality electrical energy and used it to split H and O, you now burn the H and O back to H20, getting the energy back, not as electricity or mechanical motion, but as HEAT.  Now you use this heat to drive a heat engine and lose maybe 2/3s of it to the carnot cycle limit and more to other inefficiencies.

Net result is less than 1/4 of your mechanical/electrical power from the power plant ends up as mechanical power in your engine.  If the plant is oil fired that translates to 4 times as much carbon dioxide in the air as if you'd burned the oil directly, far more if the plant was coal fired (since most of the energy in oil is from burning the hydrogen.)

If you're going to electrically-produced hydrogen fuel you should be using a fuel cell, which doesn't suffer from the heat engine's inherent limits.  (It's a glorified battery and can in principle get out nearly all of what went in.)  Otherwise you're trading clean air here for four (or more) times dirtier air somewhere else.

If it's global warming you're worried about (rather than, say, local smog) remember that the power plant and the freeway are sharing the same planet's atmosphere.  (If it's cost you're worried about, why are you buying four times as much oil to run your car?)  If you somehow manage to make your own hydrogen from A.E. sourced electricity, why are you burning four times as much of it to run your I.C. car or genny as you would to run your fuel-cell car or homepower system?

[nanotech]

For me, the only way to answer your questions is with one answer : COST!!

The cost of a fuel cell big enough to get you the same distance as your current gas tank would is prohibitively expensive.

Also, there is only enough platinum in the world to make enough fuel cells to outfit 2/3 (I think) of the cars on the road currently.  And considering the fuel cells would only last one year......

Plus the pollution for mining the platinum in the first place.

The object with converting a car to run hydrogen through its internal combustion engine is to reduce the pollution produced in the actual construction of the car in the first place (which is FIVE TIMES what will EVER come out of the tailpipe of a car that travels 200,000 miles in its life).

So in your example of oil-produced electricity creating four times the pollution when used to convert it to hydrogen, you're still one times ahead of the game over producing a car from scratch that was designed to run specifically on hydrogen or electricity in the first place......

[nanotech]

But then again, I just noticed that the BMW link was for a car built from scratch.

Sorry about that.

I've got my mind almost 24/7 on the track of how to convert a gasoline powered car to run on hydrogen in the most expeditious and safe manner possible.

As I will be producing the hydrogen from wind power, I'll essentially be driving my car for free (after the replacement cost of the conversion, of course).

Now, why don't I just use the wind power to charge a battery pack and drive an electric car?  Because I live a 90 mile round trip from work.  In northern Minnesota.  With no plug in at work.

So I would need three complete banks of 18 Trojan T-105's to make the round trip.  One bank for the drive down, one bank for the return trip, and one bank to run the heaters to keep the whole works from freezing when the temp drops to 50 below zero!!

Now, what type of vehicle is going to be able to carry 54 batteries weighing in at 62 pounds each for a total battery bank weight of 3,348 pounds?

Plus the cost of buying 54 of said batteries every three years.

Oh, and I would also need an additional 6 banks at home to charge the car off of at night!!  (3 to charge it, 3 in case there was no wind that day)

So we're talking about a MAJOR outlay in cost just for batteries, let alone the motor, speed controller, DC-DC converter, vacuum pump, electric heater core, motor power cabling, contactors, meters and gauges, battery tray to hold that much weight still in case of an accident, etc, etc, etc.

Also, the car would HAVE to be a stickshift as automatic transmissions DO NOT like coming to a complete stop at the input shaft, then being expected to go again without any spin-up.  (auto boxes require the fluid pump to be going at all times)

Now, what would I need to convert my wife's Neon with its automatic tranny to run on hydrogen?  A storage medium and a reprogramming of the fuel injection and ignition computers.  Possibly a new stainless steel exhaust to prevent total rust-through in a month or so of the moisture-laden output of running on hydrogen.  

How much weight would it add to the car?  Depends on the storage medium.  Hydride canisters from United Nuclear (http://www.switch2hydrogen.com/) don't look like they weigh too much considering they're putting 650 miles' worth in a Corvette, which isn't known for having a terrific amount of cargo hauling capacity!!

So, which would you prefer?  Buying $10,000 worth of equipment from United Nuclear once?  Or buying $10,000 worth of equipment from multiple sources, have to put the pieces together like a poorly thought out jigsaw puzzle (hoping like heck that it all still works when you're done) and then buying 162 batteries at a cost of $84.90 each every three years ($4,584.60 a year)?  Plus the fact that even a Ford F-350 Super Duty would be taxed to its limit with the weight of all those batteries.....

I know which one I would prefer.

[benjamindees]

Yeah well fuel cell cars don't exist yet, and if they did, they'd be about $100,000 each.  And in the spirit of the Dans, "I can't build one in my shop".

I know this isn't a very efficient way.  In fact, I know everything you told me.  But it's a way.  Hydrogen is a chicken/egg problem.  Internal combustion is an old chicken that can be made to reproduce with some effort.

Besides, hydrogen can be stored more cheaply in bulk and for longer than batteries.

I don't have any oil wells.  I don't have a corn or soybean field or fertilizer.  I have wind, and sunlight, and grass, and some sticks and twigs.

And I'm not here to save money.  I'm not here to follow a few howto guides and pat myself on the back for generating 5% of my energy use.  I'm certainly not here to go back to some turn-of-the century lifestyle.  I'm here to find a way for people with no more resources than I have to provide for all of their energy use, and beyond.

The vast majority of energy is spent on transportation and heating.  Batteries are near worthless for those applications.

[nanotech]

"The vast majority of energy is spent on transportation and heating. Batteries are near worthless for those applications."

Sums it all up in one neat sentance!!  

[benjamindees]

I've got my mind almost 24/7 on the track of how to convert a gasoline powered car to run on hydrogen in the most expeditious and safe manner possible.

Please please please choose safety over speed.  The reason I'm bringing this up on this forum is that there are lots of expert experimenters here.  And this is a great place to collaborate and share information before anyone jumps into anything that could hurt themselves.

I noticed today there is a wealth of information available in US libraries via interlibrary loan.  Many studies and reports have been written on this topic, surprisingly quite a few in the 70s.  We just need to find them.  Also, lots of tips can be gleaned from articles via Google.

But safety really is the most important thing.  There will be plenty of time to save money on gas.  I'm just wanting people to start thinking about all of their options.

[electrondady1]

i don't have the numbers but is h2 much less powerfull as a fuel than natural gas ch4.? i have spoken to a local guy  who does propane converions. i was under the impresion it would be a matter of changing orifices. these conversions  allow the retention of the gasoline system . allso,introducing a small amount of hydrogen into the gasoline/air mixture is supposed to be very helpfull . i'm not really shure as to why storing the hydrogen in a conventional pressure vessel is so problamatic. is it just the size of the molecule? or does the h2 corrupt the tank material?  

[finnsawyer]

A couple of comments:  The situation with batteries could change overnight as there are chemical reactions much more efficient than that in lead acid batteries.  I also seem to remember that building dump loads is fairly common when the batteries are full.  That power is just begging to be used.  In that case hydrogen generation may make sense.  I also remember one site touting the adding of hydrogen to the carburetor of a gas engine to save gas.  So hydrogen may have its niche for the home experimenter.

[electrondady1]

alot of guys here talk about heating water as a good dump load. as i mentioned on the "doesen't matter" thread, the process of electrolysis heats the electrolite. i am unshure as to what percentage of current is transformed into heat but it might be a way of haveing your cake and eating it too.

 ive come to the conclusion that for me the most flexable household heating method would be a multi fuel, circulating, hot water system. if in the process of creating fuel for my truck i was helping to heat my house,well, that would be ok!

[benjamindees]

Apparently another of the big problems, that I neglected in my writeup, is hydrogen embrittlement.  Because of the size of the hydrogen atom, it seeps into almost any material.  In metals, this can cause a complex series of reactions that weaken the metal over time.  There are pressurized hydrogen storage tanks, made by companies such as Dynetek, but they are reinforced with carbon-fiber.  And then there is the issue of compression, which could be problematic.

As for power, yes I believe hydrogen as a gas at STP is less powerful than any of the fossil fuels.  I don't know how this affects things such as compression ratio, cylinder size, injection rate, air mix, etc...

[electrondady1]

   to make up for its lower energy density, turbocarged engines can be utilized  to bring the output up to were it should be .you ought to be able to smoke the tires a little bit.just to let people know it's got power and it cool!

   it might be our duty to the hydrogen economy

  if your runing in a supercharged state you can use the manifold pressure to squirt in all kinds of stuff, water/alcohol mixtures. it would be possible to make the engine quite powerful .

   or with those aids you could make the engine smaller.

   hydrogen has a lower combustion temp.i think it's less prone to detonation or preignition.under those conditions it would be posible to manipulate the compression ratio,ignition timing, i would think a different operating temp(thermostat) might be interesting.  with the turbo you should run an ecomomy style camshaft with greater lobe seperation that should help exaust gas temperatures.

  sounds like i want to build one!

 

[electrondady1]

i got a chance to use the link nanotech posted and read the whole write up from united nulear. it seems they are not really ready to go yet. there is no mention of a soution to embrittlement  

perhaps ceramic engine components would be required.?

[electrondady1]

 did a quick google search for ceramic engine components they exist mostly for racing or extreem duty stuff. if your thinking of runing an ic engine on hydrogen,you might need to use components that would be imune to embrittlement.  if your thinking of a long term investment it only makes sence to start with a fresh engine anyway.

[maker of toys]

hydrogen embrittlement is mostly a problem for storage tanks and fuel lines; stuff that will be constantly exposed to h2 at elevated pressures and possibly extreme temperatures.

the engine itself will only see hydrogen when its running, and the hydrogen would much rather oxidize vigorously than migrate into the structure of the engine.

so I wouldn't worry overmuch about the engine.

ceramics in other parts are likely to just trade one problem for another;  ceramics have lots of microporosity, and hydrogen will migrate through the material that much faster as a consequence.  they're already brittle into the bargain, so I can't see it helping much on that front.

-Dan

[Aelric]

just a few comments :-)

I agree on H2 as a fuel, I think IC engines or turbine engines could be made much more sustainable to the RE enthusiast with H2.  An electrolizer, a power source, a tank (possibly a metal hydride tank could even be a way to get some refrigeration and water heating out of the mix too :-)  when metal hydride releases hydrogen its exothermic, forms ice on the outside... there is an article on homepower about it, when it absorbs hydrogen it is endothermic)   There is even a site online that is marketing a system like that, uses metal hydrides to store hydrogen, then in turn makes hot water and refrigeration and power all at the same time.   Just interesting info to me.

At any rate, on the ceramic subject, another option would be to coat the parts with ceramic, I found a website for Cerramacrome, not sure if it would be great for the job but apparently it can handle some high heat and is used in some higher performance cars/trucks.  Just a suggestion.  One thing I had thought of was using it as a potential backup genny.   If you take batteries out of the equation and just use  homemade H2 in a IC engine or Turbine engine.  Anyway just a few ideas hehehehe.  Have fun and keep us posted on what you find, when I get a place I am thinking of doing some experimenting myself.  Plan to start small and work my way up.   Maybe an old push mower converted to H2.

[bob golding]

hi all,

 a much simpler solution is to  change to a diesel engined vehicle, and  make your own  bio-diesel. its cheap, carbon neutral apart from the methanol, which you could make yourself, and easily available. even if you buy cooking oil from the local store. hydrogen is not a practical solution yet,and i cant see it ever becoming one for the reasons stated by others. fuel cells likewise unless someone comes up with a  differant catalyst than platiunum.to see what platimun mining does to the enviroment just look up "kola peninsula" and russian nickel mining. the only way i can see hydrogen technology being clean is to  make it using hydro electric power and  transporting it as hydride. that still leaves the catalyst problem though,and the transport.

bob golding