Naked Science Forum
Life Sciences => The Environment => Topic started by: Voxx on 04/07/2012 00:44:34
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This is a theoretical question for if we make Hydrogen Cell Fuel a clean large scale energy solution.
Theoretically we would be using the ocean as we already have serious problems with fresh water supplies for meeting our living needs.
1: What will dumping all that water into the atmosphere of urban areas do?
2: What will happen in the places we take the water?
3: What about all that oxygen released when making hydrogen fuel from water and is that going to become an issue?
4: If we use this kind of solution can we power the hydrogen cell fuel process like a dam?
5: Theoretically if we were to use hydrogen cell fuel through the ocean we would have to first purify it, correct? If so could we use the movement of the boiling water as energy as well?
6: What could we do with the left over salt? Is there a way to gain energy through the left over salt?
Thank you for all the help you guys give.
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This is a theoretical question for if we make Hydrogen Cell Fuel a clean large scale energy solution.
Theoretically we would be using the ocean as we already have serious problems with fresh water supplies for meeting our living needs.
1: What will dumping all that water into the atmosphere of urban areas do?
Only a little more than we already get from burning gasoline and other fuels. Probably significantly less than daily evaporation. However, there are notes of potential negative impacts from water vapor in Jet Streams. H2 jet fuel might increase the high altitude water vapor.
2: What will happen in the places we take the water?
If it is used locally, then most of it will come back down in the form of rain. There are concerns of subsurface water depletion, especially in arid areas (where one might make solar-electric generators).
3: What about all that oxygen released when making hydrogen fuel from water and is that going to become an issue?
NO!!!! It gets recombined with Hydrogen to form Water (except for a small amount of H2 loss). Keep in mind that atmospheric oxygen is about 20%. In a century of burning fossil fuels, we've increased the total CO2 content (percent) in the air by about 0.02%.
4: If we use this kind of solution can we power the hydrogen cell fuel process like a dam?
Perhaps. However, we would need a good method to store the hydrogen, either as high pressure gas, or low pressure cold liquid (plus recovery system). Dams are effective because the relatively small containment structure and relatively large reservoir of water. And, in most cases, they are self-filling. Ideally, one would not produce more hydrogen than would be required for a few days of usage, unless one uses a seasonal power source such as solar.
5: Theoretically if we were to use hydrogen cell fuel through the ocean we would have to first purify it, correct? If so could we use the movement of the boiling water as energy as well?
Maybe. However, one of the problems with water is that it is a relatively poor conductor of electricity. Various salts are added to improve the conductivity. Saltwater already contains an ionic salt. The biggest problem with doing electrolysis on salt water is that chlorine gas can be also generated in the process which would be undesired, unless one could also collect and utilize the chlorine. using NaOH or KOH as a conductive salt is far less likely to create undesired gasses.
So, yes, the chlorine might be enough of a problem that one would not want to do electrolysis on sea water.
6: What could we do with the left over salt? Is there a way to gain energy through the left over salt?
One might be able to create an osmotic pressure gradient with the salt. However, It might be difficult to use to produce significant amounts of power.
There is demand for a significant amount of salt, much of which is being mined from ancient dried up sea beds. However, doing significant amounts of desalination or otherwise removal of water from salt might overwhelm the demand. But, it might help stop the process of mining salt.
It would depend on the desalination process. One likely would not take it to the point of creating dry salt, but rather one might choose to choose to create a brine which would then be released back into the ocean. It could create a local salty region, but as the hydrogen is burnt, becomes water, and returns to the ocean, the overall impact would be minimal
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Thank you as always for your quick response Clifford.
Only a little more than we already get from burning gasoline and other fuels. Probably significantly less than daily evaporation. However, there are notes of potential negative impacts from water vapor in Jet Streams. H2 jet fuel might increase the high altitude water vapor.
So there might be an increase in rainfall if one was using this method of energy to power an entire city?
If it is used locally, then most of it will come back down in the form of rain. There are concerns of subsurface water depletion, especially in arid areas (where one might make solar-electric generators).
Would it make any difference to use a pipe quite a bit further under the surface of the water?
NO!!!! It gets recombined with Hydrogen to form Water (except for a small amount of H2 loss). Keep in mind that atmospheric oxygen is about 20%. In a century of burning fossil fuels, we've increased the total CO2 content (percent) in the air by about 0.02%.
Thank you for clarifying me on that.
Perhaps. However, we would need a good method to store the hydrogen, either as high pressure gas, or low pressure cold liquid (plus recovery system). Dams are effective because the relatively small containment structure and relatively large reservoir of water. And, in most cases, they are self-filling. Ideally, one would not produce more hydrogen than would be required for a few days of usage, unless one uses a seasonal power source such as solar.
Storage: Would we be able to convert the hydrogen into electric energy and store it in high tec. capacitors?
Dam: My thought is running the initial process of bringing the water into the containers of the saltwater and the heating of it to be powered through the dam's electrical buildup.
Production: If we were able to store this power in capacitor's the process could be stopped and the filters would need regular cleaning so there could be a weekly, daily or however long it would take to fill the capacitors cleaning schedule.
Maybe. However, one of the problems with water is that it is a relatively poor conductor of electricity. Various salts are added to improve the conductivity. Saltwater already contains an ionic salt. The biggest problem with doing electrolysis on salt water is that chlorine gas can be also generated in the process which would be undesired, unless one could also collect and utilize the chlorine. using NaOH or KOH as a conductive salt is far less likely to create undesired gasses.
Alright, so if you can separate the pollutants from the water and the salt, could you reintroduce the salt into the water to make the electrolysis more effective?
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New Questions
1: I know saltwater is very corrosive; is there any metal that is noncorrosive towards saltwater?
2: How hot can this metal become before it takes warping effects?
3: At what temperature does saltwater boil?
4: How do hydrogen cell engines work and do they supply a source of electricity or some other kind of energy?
5: Could you create some kind of energy gathering process for the boiling water, this way it would generate more power by the movement of the water?
6: Can you use ferrites (magnet) to move water without a direct electrical current?
7: How much hydrogen would it take to power a large city metropolis?
8: How big would this energy plant have to be to supply this much power?
9: Can you see any problem's off the top of your head with this idea?
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If it is used locally, then most of it will come back down in the form of rain. There are concerns of subsurface water depletion, especially in arid areas (where one might make solar-electric generators).
Would it make any difference to use a pipe quite a bit further under the surface of the water?
The problem is...
Say I have a 20' well.
And, you put in a 100' well, and suck down the water level by 50'.
Well, I would get quite irate when my well goes dry.
The speed of replenishment of the subsurface water would depend on the region. I presume that most of the subsurface water is replenished every year in western Oregon where we get plenty of rain in the winter. But, in more arid regions, it may in fact be very old water, and may only turn over on the scale of thousands of years.
There is also briny water at a depth of about 1000 feet. However, I don't know if anybody really knows whether this briny water is actually connected to the near-surface water. So, if you pull down the the level of the briny water, will it affect the surface water levels? I presume that over time, a large depletion of deep water would actually affect the near surface water. But, there may be blending of sources over wide areas.
I doubt that we will use hydrogen gas to produce municipal electricity. It just wouldn't be practical to use electricity to produce hydrogen to generate electricity. However, hydrogen may be used to produce heat or for mobile applications such as automobiles. Our current fuel makes about equal amounts of water and CO2. Moving to hydrogen fuels might double the amounts, but it would be hard to notice the effects.
How much gasoline does a city with 10 million people use in a day? A gallon per day per person? That would mean about 10 million gallons of water from the fuel.
So, for the 10 million person city, say 50 miles x 50 miles, or about 2500 square miles. That gives you about 4000 gallons per square mile. Divide that by 640 acres per square mile, and one gets about 6.25 gallons per acre. Hmmm....
Anyway, assuming the water from the fuel gets distributed over both urban and rural areas, the total impact will be minimal.
You could use the steam generated by distillation to run both a generator, as well as re-condensing it to make distilled water. Steam pressures would be different for a generator and a distillation unit, but perhaps one would still choose to combine technologies. There may be other membrane based water purification methods that would require less energy.
Silicon bronze is commonly used in the boating industry, and generally resistant to seawater. It is much different than brass.
I doubt you could move water with fixed permanent magnets. There are a number of different types of pumps. In days of past, windmills were common for pumping water from shallow wells.
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Alright, from what you touched on let me see what I've gathered.
I can see the effect that dropping the water level could do, but if your taking it from a source such as the ocean; in a place such as say Miami, would the water levels really drop that horribly with how vast the Ocean is?
I don't know whether pumping the source water from near seafloor or from the surface would be more economical, I'll need to research that myself I guess.
I know it seem's a bit redundant to use a dam like system and the steam to run a generator to also contribute towards an energy resource and then to use that electricity generated towards electrolysis for hydrogen fuel cells. But what I'm trying to find out is if it would produce a greater power source, would hydrogen be a more economical and cost efficient method to our energy problems? So what I really want to know is if Hydrogen power is more efficient and powerful than our normal means of energy generation?
I had little hope for the magnetic's theory, but thank you for indulging me.
Thank you for mentioning Silicon Bronze, I'll have to look further into it.
It seem's as if it would take a large amount of water to convert to hydrogen to supply energy for an entire city? Is hydrogen really that weak of an energy source? I just presumed hydrogen had much more energy than that, I guess I got the wrong idea?
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Question's I would still like to know:
1: So there might be an increase in rainfall if one was using this method of energy to power an entire city?
2: If you can separate the pollutants from the water and the salt, could you reintroduce the salt into the water to make the electrolysis more effective?
3: How hot can Silicon Bronze become before it starts warping?
4: How big would this energy plant have to be to supply enough energy to power a city like Miami?
5: Can you see any problem's off the top of your head with this idea?
6: Would it be more effective to supply the purified water to the whole city and then have each house with their own Hydrogen Fuel Cell Generator?
7: How loud do you expect the process to be?
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As you would have a cycle. Generate Hydrogen. Burn to make water... Water goes back to ocean. Thus, you can not drop the ocean levels. You can look up the volume of the ocean, but it is quite large.
I don't have the workability temperatures of the bronze, but it can get much higher than the boiling point of water if you are planning on making boilers. The melting point is about 1866°F. While there is some line loss with transmitting electricity, for the most part it will be more efficient to use electricity wherever applicable rather than multiple transformations.
Look up on the internet Bloom Energy (http://www.bloomenergy.com/) and Bloombox. There are some good YouTube videos with some basic information.
If you have a salt-free solution for electrolysis,
Then you would add something like Sodium Hydroxide (NaOH) or Potassium Hydroxide (KOH) to avoid the production of chlorine gas. The lye would act as a catalyst and would not be consumed. So, you could add the lye once, and then keep adding clean water.
You need energy to make the hydrogen. No sense in supplying fresh water to a house and expecting the owners to magically make their own energy. Well, that is unless you are also planning on supplying a nuclear reactor to every household.
There are some people with home wind or solar generators that have experimented with also making and storing hydrogen gas. But, having a million homes with personal hydrogen generators would be a good formula for a disaster.
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As you would have a cycle. Generate Hydrogen. Burn to make water... Water goes back to ocean. Thus, you can not drop the ocean levels. You can look up the volume of the ocean, but it is quite large.
I don't have the workability temperatures of the bronze, but it can get much higher than the boiling point of water if you are planning on making boilers. The melting point is about 1866°F. While there is some line loss with transmitting electricity, for the most part it will be more efficient to use electricity wherever applicable rather than multiple transformations.
Look up on the internet Bloom Energy (http://www.bloomenergy.com/) and Bloombox. There are some good YouTube videos with some basic information.
If you have a salt-free solution for electrolysis,
Then you would add something like Sodium Hydroxide (NaOH) or Potassium Hydroxide (KOH) to avoid the production of chlorine gas. The lye would act as a catalyst and would not be consumed. So, you could add the lye once, and then keep adding clean water.
You need energy to make the hydrogen. No sense in supplying fresh water to a house and expecting the owners to magically make their own energy. Well, that is unless you are also planning on supplying a nuclear reactor to every household.
There are some people with home wind or solar generators that have experimented with also making and storing hydrogen gas. But, having a million homes with personal hydrogen generators would be a good formula for a disaster.
So in short, it would be possible to do something like this, but it has very dangerous risks, it isn't the most efficient method of energy creations and there would be a lot of problems with supplying an entire city off this power?
What other alternative fuel source are we exploring that could have the potential to be clean, energy efficient, powerful and safe?
1: Irrigation of the water supply? By putting turbines inside our water movement through a city could you generate enough power?
2: What about a Buoyancy Engine? Personally I don't think this would be an optimal way of powering an entire city, but i don't have a full understanding of the technology. Just a thought, but what if you could incorporate the Buoyancy Engine, Turbines and Hydrogen Fuel Cells into a possible power source? I know it seems a bit complex, but just trying to figure out a method.
3: A sudden idea struck me that I most likely didn't think through properly, but what if you created a system for the turbine at say a ocean cliff. You would have a mechanical system that would have two door's or release valves. One at a higher elevations and one at a lower, the higher valve would open and let water run in and turn the turbines. It would only allow a certain amount in and it could be calculated with some safety factor. After that the top valve shuts and the water does its course set by gravity going down a ladder of sorts. It would reach the bottom and the water would enter a room that would seal the water in and the bottom valve would open. There would have to be some kind of vacuum system to throw back the water, but is that a workable solution for power?
Something I stumbled on; As BC pointed out, there are no hydrogen mines. Hydrogen has to be manufactured by processing something that is a compond of hydrogen to release the pure hydrogen. This processing consumes a larger amount of energy than the manufactured hydrogen is able to produce.
If this is true, then how do Hydrogen Fuel Cell Car's run without suddenly dying as soon as you turn the key? I now see what he was talking about, it requires more energy to create outside of the engine than what is created inside. Couldn't this be remedied through the dam and other methods for the conversion? I mean isn't hydrogen fuel very clean and wouldn't it be a prime remedy for fossil fuel?
I've been going over a few topic's on Naked Science about hydrogen and from what I can gather, the biggest problem is storage correct? If this was remedied would it be the best solution?
What about splitting the hydrogen and oxygen, then transporting them through the city separately to the points of which you need power. Then feeding the chemical process into a local generator to create the energy?
What about using methanol to create Hydrogen and Carbon dioxide? Can we use carbon dioxide as an energy source, while also using the hydrogen created to generate our fuel cells?
Hmm, It would require energy to create this cycle and money for workers, maintenance and transport ect. The energy isn't free, so another question i have is whether it would be cheaper than fossil fuel?
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You can't have "free energy" like you are hoping.
As far as the hydrogen fuel cell cars. They have a hydrogen tank, either high pressure gas at room temperature, or low pressure liquid at very cold temperatures. Or, there have been efforts to make a matrix to absorb the hydrogen gas, requiring lower pressures. The cars would fill the tank with hydrogen at a filling station, much like you fill your car with gasoline.
A rocket must carry both hydrogen and oxygen because there is no access to oxygen in outer space. However, on the surface of Earth, there is not that limitation. It is easier to just transport the hydrogen. Release the oxygen into the atmosphere, then use atmospheric oxygen for the reaction.
Many cities use elevation to create water pressure. In a hilly region, reservoirs are put on the top of hills. It often takes energy to pump the water up to the reservoirs. If you put turbine generators into the water distribution lines, you would lower the pressure going to the houses. This might be appropriate in the areas with a significant elevation changes, but it would not be appropriate in more flat locations, or in places with inadequate size of distribution lines.
You can't gain energy by artificially raising and lowering water. Typical hydroelectric generates depend on a natural force to raise the level of water. For example rain at a higher elevation, and a mountain stream that takes the water down the mountain.
There are also some underwater ocean currents driven by subtle changes in seawater density, either due to different salinity, or different temperatures and densities of the water. And, of course, also waves and tides that could potentially also be used to generate energy.
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You can't have "free energy" like you are hoping.
Is this referring to my thoughts on the dam or the comment on the levi system?
As far as the hydrogen fuel cell cars. They have a hydrogen tank, either high pressure gas at room temperature, or low pressure liquid at very cold temperatures. Or, there have been efforts to make a matrix to absorb the hydrogen gas, requiring lower pressures. The cars would fill the tank with hydrogen at a filling station, much like you fill your car with gasoline.
So the storage is the biggest problem with this solution and if that was fixed there would be no problems?
A rocket must carry both hydrogen and oxygen because there is no access to oxygen in outer space. However, on the surface of Earth, there is not that limitation. It is easier to just transport the hydrogen. Release the oxygen into the atmosphere, then use atmospheric oxygen for the reaction.
My mistake, I thought that the oxygen had to be in a completely pure environment for the hydrogen cell process to be optimal?
Many cities use elevation to create water pressure. In a hilly region, reservoirs are put on the top of hills. It often takes energy to pump the water up to the reservoirs. If you put turbine generators into the water distribution lines, you would lower the pressure going to the houses. This might be appropriate in the areas with a significant elevation changes, but it would not be appropriate in more flat locations, or in places with inadequate size of distribution lines.
That might be true in the case of a lake or river, but I don't think it would be that big of a deal within the ocean? I don't know how much energy would be spent and generated with the process of it, but I was hoping the process would produce more energy than it used.
You can't gain energy by artificially raising and lowering water. Typical hydroelectric generates depend on a natural force to raise the level of water. For example rain at a higher elevation, and a mountain stream that takes the water down the mountain.
Yeah, I was grasping at straws with that one.
There are also some underwater ocean currents driven by subtle changes in seawater density, either due to different salinity, or different temperatures and densities of the water. And, of course, also waves and tides that could potentially also be used to generate energy.
Very true, is it the environmentalists that prevent us from using this form of energy since sea creatures ride these currents for migration?
Btw, it seems like your the only one that will touch my posts as of late T_T