Home Hydrogen Generator

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crashsite said:
But, what does any of that have to do with the generation and storage of relatively small and low pressure quantities of gaseous hydrogen?

Small amounts of low-pressure hydrogen will only produce a small amount of energy. You would need to do a cost analysis to determine whether it is worth it. There will still be safety concerns.

We got onto liquid hydrogen because of a statement that hydrogen was liquid at something like 5000 psi, which it is not unless the temperature is low enough. One must be at or below the critical temperature to have a liquid state. Once at that temperature, LH2 can be handled like any other extremely cold liquid. The problem is that that temperature is very low and difficult to maintain. For example, it is below the condensation point for air, which will condense on its surface. That is not good, if you want to avoid mixing liquid hydrogen and oxygen in your home.

This all relates to the real life problem of using hydrogen as a commercially viable fuel. It is not that the problems can't be solved, but I don't believe the solutions are in the immediate future. So, current technology leaves us with choosing between dealing with low temperatures, high pressures, or adsorbing the hydrogen to a carrier from which it can be desorbed at the point of use. John
 
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jpanhalt said:
adsorbing the hydrogen to a carrier from which it can be desorbed at the point of use. John

That brings up another question:

I have seen this as a safer storage solution in cars but, don't really know how it relates to the big picture. Certainly hydrogen can be locked up in appreiable quantities in hydrocarbons (and carbohydrates). You can burn a chunk of wood or coal or petroleum and get substantial amounts of energy from it. Again, my chemistry ignornce comes to the forefront since I don't know the mechanism by which so much hydrogen can be so conveniently stored.

But, if that hydrogen can be absorbed and desorbed, in a man-made storage container, I'm not sure why a home generator could not perform that function as well as anyone else (unless it takes heroic measures to do it).

But, the general consensus seems to be that insufficient hydrogen could be produced this way to make it worth while. And, with that I will shunt this line of thought to a back burner and move onto my next "project".

Tnank you all for all your input, suggestions and ideas.
 

It's basically cost per energy unit stored. The adsorbents are often rare metals, like platinum. General Motors, I believe, is still working on the storage units. Liquified hydrocarbon gases, primarily methane, propane, and butane, I believe have greater promise. Methane, for example, gives you 4 hydrogens per mole instead of just the 2 that you get with hydrogen, and a carbon thrown for free

More seriously, combustion of hydrogen produces 120 MJ/Kg; whereas, combustion of methane produces 50 MJ/Kg. So yes, hydrogen produces more energy per Kg than methane, and that is important if you are building rockets where weigt is such a limiting factor.

However, if the tank is sitting in my back yard, I don't care how much it weights; I care how long it will last between refills and the cost. So, lets look at the energy from the standpoint of volume. I will spare you the calculations of converting from mass to moles to volume at standard temp and pressure. If you do that, hydrogen produces 0.24 MJ/mole (0.0107 MJ/L) and methane produces 0.80 MJ/mole (0.036 MJ/L). Thus, per unit volume of gas, methane produces over 3 times as much energy. Moreover, methane (and the other gases mentioned) can be readily liquified to increase even more the amount of energy available per unit volume stored. John
 
Pommie said:
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I also think that if wind is supplying less than 2% then it is not worth the eyesore that they are.
Mike.

Many of the best location for turbines have very low populations. Think square miles per person. The people who live in these areas often own the land and are more then happy to host a wind farm. Income from a wind farm is much greater then can be made by ranching or farming the land. And you still can farm or ranch as the space used by the towers is small.

Wind power is a sleeping giant. I have no idea what the practical limit on the numbers of generators that could be installed is world wide. It seems that there are vast areas in the US central plains states with enough wind to make it profitable there. As the generators improve (become cheaper) the number/size of profitable locations will increase. An increase in energy prices has an greater effect.

Wind power is not attractive to governments because it is not attractive to big energy. One can start a wind farm with far less money then it takes to build a traditional power plant. That might lead to completion and reduce the cost of energy. Is big energy willing to let that happen?

For that and possibly other reasons you do not see much official positive interest in wind power. But unless government and or BB takes aggressive active steps to stop it, it is going to happen.

The area where I live is quite windy. At one time we were told there was not enough wind to justify turbines. Last year a company came through and leased many square miles of land to do just that.

When I was growing up I seen the same pattern with oil leases in the Midwest.

Unlike an oil well a wind turbine does not go dry.

There are a few ifs here. But I am some what sure that it may in be in part true... It could be that we have only scratched the surface of wind power.
 
What about the noise pollution from wind turbines? Some people are very sensitive to the low frequency sound produced. It is virtually impossible to insulate against it, because of its low frequency. Low population density doesn't mean none, and the sound travels for miles.

Second, assume we got more than a trivial amount of energy from wind. Would weather patterns be disrupted?
John
 
Here in Texas windmills (power not water) are becoming common, especially in West Texas.

https://www.flickr.com/photos/unwiredben/14425149/

The link show a high altitude photo of a string of power production windmills. The blades on each windmill is about 60 feet in length (that 2 blades = 120 feet).

Wind is viable...but hardware cost, space, dead birds can each present issues.

Personally I wish a small H2 generator was viable. I do remember some years ago reading about someone that had commercially produces a welding rig that used H2 generator. It was produces as 'Brown's Gas'. I thought for a while someone would take this and do something but nothing that I have heard of.

Also, I seem to remember from chemistry class (early 1970's) my instructor talking about H2 production and said that it did not matter if you used 1.5vdc or 300vdc that the production would not progress faster with more voltage. This had always bothered me because logic says different but I never had a chance to test this. Does anyone know if this is the case?

RLJ
 

Noise is not an a real issue because as I said in my post most of the prime areas are populated in square miles per person not people per square mile. And the cows do not care.

In regard to the weather pattern. Power generation from wind is very passive. Think about the huge amount of heat released by a coal fired power station. That would have a much larger impact then slowing the wind down bit.

Wind is driven by existing heat energy. By harvesting that energy instead of burning carbon ... what ?
 
hi,
One the problems we are experiecing in the UK with wind turbines, is the accumulation of dead 'bugs' on the leading edge of the blades.
The dead bugs provide a soup for the build up of micro organanisms, which cause a large drop in efficiency by spoiling the aerofoil section of the blade.

They have had to install anti bacterial sprays on the towers to spray the blades from time to time.
 
3v0 said:
Noise is not an a real issue because as I said in my post most of the prime areas are populated in square miles per person not people per square mile. And the cows do not care.

You know, the windmill farm could be made even more productive by locating a nuclear waste dump on the same site. Afterall, there is no one around to be bothered by it

I don't believe that low population density is a very acceptable excuse for doing something as disruptive and potentially disruptive to the environment and fauna as would be produced by widespread use of windmills. Not-in-my-backyard logic has a way of becoming everyone's problem.

It is a straw-man argument to justify wind power based on comparison to a single alternative: inefficient coal-based plants with lots of heat loss. There are other alternatives, including but not limited to nuclear and gasification.

As for the effects from "slowing the wind down a bit," I am less optimistic they would be negligible. A 1 °C increase in global temperature, which is less than a 0.5% change, has been predicted to have an enormous impact. Turbulence and direction of wind also affect weather, not just velocity. John
 
I know this is off topic a little but here is possible reply to the last post...

**broken link removed**

RLJ
 
jpanhalt said:
You know, the windmill farm could be made even more productive by locating a nuclear waste dump on the same site. After all, there is no one around to be bothered by it

How can one person be so wrong about anything?

What disruption! You must be thinking of the propaganda dreamed up by big energy.

How do you see this as a "Not-in-my-backyard" deal when the people who own the land want the turbines. If you do not own a pasture or a wheat field you have no reason to live in one. The people who own this land would greatly benefit form the income. Population centers are often 20 or more (much more) apart. Lots of room for turbines.

How do you see the a wind turbine as causing global warming. You are uninformed.

broken link removed
The Sierra Club
Underline is mine.

And as pointed out by RLJ in the previous post quited turbines are possible for areas where that would be a problem. That makes them even more of possible solution.
 
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3v0 said:
How do you see the a wind turbine as causing global warming. You are uninformed.

Sorry to have confused you by giving an example of how a small change in average temperature (i.e., less than 0.5%) is predicted to have a big impact on our climate and life in general. That comment was made in reference to your comment that any effect of on winds would be small. My statement was:

jpanhalt said:
As for the effects from "slowing the wind down a bit," I am less optimistic they would be negligible. A 1 °C increase in global temperature, which is less than a 0.5% change, has been predicted to have an enormous impact.

I did not mean to imply that large-scale use of windmills would produce global warming. They may affect the weather, which was my point. Whether that effect will cause cooling, warming, or have no effect on temperature is unknown, so far as I know. In retrospect, I should have added a few extra word to make the comparison clearer. John
 
It is difficult to take you seriously when you toss out remarks like the following.
"You know, the windmill farm could be made even more productive by locating a nuclear waste dump on the same site."

You will have a difficult time convincing anyone that your statement below is not about global warming.

A 1 °C increase in global temperature, which is less than a 0.5% change, has been predicted to have an enormous impact.

Wind is a result of solar heating. Any solar energy collection device, including turbines, will reduce wind. Should we abandon all forms of solar energy for that reason.

Large building block the wind, vast expanses of pavement trap rather the reflect the solar energy. What about deforestation of the rain forests. The farmland that replaces it will have a vastly different heat absorption rate then the trees. The point is we effect the solar/wind of the planet in many ways and directions.

Current thinking is that there will be increased violent weather due to global warming. Maybe reducing the wind speed a bit would moderate that. It would be nice. We know buring less carbon will help moderate it and wind farms will help with that.

If you think there is a real problem with the possible wind slowing due to turbines find some evidence to support it, then put it perspective. To say so without is fear mongering.

Collected and re-purposed solar/wind energy is about as close as you can come to zero environmental impact.
 

Be vewwwy careful of those carats (><) in your posing, young man! You can <b>reveal</b> your secrets....as I just did........
 
Square Brackets

wmmullaney said:
Ha, doesn't work, does it? (I had the same problem)

I don't usually use the "advanced" option and just put in my own HTML tags but, they themselves seem to be inside a quote and need the square brackets. Also, there's seems to be a fairly limited number of tags supported but, plenty enough for [font color=#ff50a0]me[/font]. See, not all the tags work.
 
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Small H2 generators don't have significant viability problems, except the fact remains that to create significant masses of H2 requires sigificant electricity.

"Brown's Gas" is the mixture of H2 and O2 you get out of electrolysis when you don't capture the bubbles forming on the 2 electrodes with 2 separate jars. It doesn't have any of the magical energy properties touted by the "free energy" crowd.

The rate of gas production depends primarily on current. Current does increase with increased voltage, but voltage alone doesn't increase the rate. For example using an electrode of half the surface area will require more voltage for a given current, but the extra voltage to produce say the same 5 amps will not increase the rate of gas generation.
 
Baby Steps

Oznog said:
Small H2 generators don't have significant viability problems, except the fact remains that to create significant masses of H2 requires sigificant electricity.

Which, of course, is why you need a "free" energy source such as solar or wind or water. Something that can just sit there and convert, convert, convert day in and day out. A little water, over a short time can wash out a road but, a little water over a long time can create the Grand Canyon.

I guess I have a little trouble believing that "baby steps" are useless. I'm thinking that 20 million homes, each with a 100 Watt solar panel could pump an average of 100 MegaWatts into the power grid (5 Watts per panel with most of the power being generated during peak load (industiral max) times). Same concept with home hydrogen generation.

Where's that darn Yankee ingenuity we Americans keep bragging about (and others keep insisting that they do even better)?
 
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