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Post by slh1234 on Oct 24, 2016 18:28:32 GMT
I've loosely followed the development toward, and of hydrogen fuel cell cars over about the last decade. For a long time, it looked to me like a good idea that would never be made feasible. Now, it is beginning to look like it might be feasible, but it still faces some good challenges. For starters, commercial models of Hydrogen Fuel Cell Vehicles are now available, and unlike what I expected, they're not really out of reach for a good number of people. I'm not advertising for anybody, but an example is the Toyota Marai: ssl.toyota.com/mirai/fcv.html. The price is really on par with the low end Tesla or mid-level gasoline powered cars. Another challenge is in production of Hydrogen. The first thought most of us had was water electrolysis, but in early days, almost all of it was actually produced from natural gas (methane), which meant it really was no improvement for people who think of use of fossil fuels as something to be reduced or eliminated (An idea I'm not opposed to. I'm just trying to be realistic about how possible that may or may not be). However; here, I see a big potential, if we change the way we think from the "Fuel station-centric" mindset to a more distributed mindset. As an example, in California, there are a number of incentives to install solar, we have a lot of wind power that makes us feel good, but doesn't lead to the shutdown of any coal-fired generators, etc. We have a good climate for the use of solar and wind power, it's just that previously, it was not something that really helped us reduce dependency on other fuel sources. With electrolysis, it seems to me that you solve a big part of the electrical storage question, and you create a system that allows you to create your car fuel when the sun shines, and fuel with you need it. Such a distributed system would be necessary for conversion to hydrogen usage on any large scale. Currently, there are hydrogen fueling stations for longer trips, but they are currently so sparse that it is very inconvenient for most people who may want to own a hydrogen car. The closest filling station for me currently is almost 20 miles away. I expect that if hydrogen is adopted more widely, then the market will follow in this area, and we'll get more stations. However; creation and shipping of hydrogen in large scale is still a challenge, I think. Maybe the need for shipping can be minimized (but not completely eliminated) by an extension of the distributed model I was thinking of for homes. And one last challenge I was thinking of is that, where I currently live, sunlight is in much greater supply than water. We have multi-year droughts that make hydro-electric an unreliable energy source, and are currently threatened with water rationing. There are two parts to what I'm thinking here, and one of them leads to a weather question: 1) Off of our coast is a large supply of salt-water. Salt in the water changes its ability to conduct significantly, and thus, changes the characteristics of hydrolysis. It also gives us additional by-products to worry about, such as chlorine gas, or salt. That makes me question the feasibility of this, but suppose we find we can deal with this. Then 2) With the number of cars on the road, if we change emissions to water, then do we change the distribution of water vapor enough to actually cause changes in weather and/or vegetation? On this, I'm remembering an article I read some time back where it was asserted that another Dust Bowl in Oklahoma (the state where I was born) was highly unlikely because of the large number of reservoirs, and ponds that have been created in Oklahoma since that time. It was asserted that this changed the distribution of water, including water vapor, and caused the weather to change significantly so that Oklahoma now receives more rain than it did previously, and receives rain in times of the year that would not happen during dust-bowl years. Interesting thought, but I don't know if that is really well-founded. So summarizing my meandering thoughts: It looks like hydrogen cars are becoming a possibility for at significant part of the population in the US. I actually wouldn't mind making my next car one if a few challenges can be figured out. We could have a distributed model of fuel production (Actually, just energy storage) with hydrogen so that we can produce fuel at home with the very products that are pushed at us in every Best Buy. But suppose we get there, what effect does it have on our climate, local or wider? I'd just like to hear what other people think on the subject.
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Post by missouriboy on Oct 24, 2016 19:39:56 GMT
I've loosely followed the development toward, and of hydrogen fuel cell cars over about the last decade. For a long time, it looked to me like a good idea that would never be made feasible. Now, it is beginning to look like it might be feasible, but it still faces some good challenges. For starters, commercial models of Hydrogen Fuel Cell Vehicles are now available, and unlike what I expected, they're not really out of reach for a good number of people. I'm not advertising for anybody, but an example is the Toyota Marai: ssl.toyota.com/mirai/fcv.html. The price is really on par with the low end Tesla or mid-level gasoline powered cars. Another challenge is in production of Hydrogen. The first thought most of us had was water electrolysis, but in early days, almost all of it was actually produced from natural gas (methane), which meant it really was no improvement for people who think of use of fossil fuels as something to be reduced or eliminated (An idea I'm not opposed to. I'm just trying to be realistic about how possible that may or may not be). However; here, I see a big potential, if we change the way we think from the "Fuel station-centric" mindset to a more distributed mindset. As an example, in California, there are a number of incentives to install solar, we have a lot of wind power that makes us feel good, but doesn't lead to the shutdown of any coal-fired generators, etc. We have a good climate for the use of solar and wind power, it's just that previously, it was not something that really helped us reduce dependency on other fuel sources. With electrolysis, it seems to me that you solve a big part of the electrical storage question, and you create a system that allows you to create your car fuel when the sun shines, and fuel with you need it. Such a distributed system would be necessary for conversion to hydrogen usage on any large scale. Currently, there are hydrogen fueling stations for longer trips, but they are currently so sparse that it is very inconvenient for most people who may want to own a hydrogen car. The closest filling station for me currently is almost 20 miles away. I expect that if hydrogen is adopted more widely, then the market will follow in this area, and we'll get more stations. However; creation and shipping of hydrogen in large scale is still a challenge, I think. Maybe the need for shipping can be minimized (but not completely eliminated) by an extension of the distributed model I was thinking of for homes. And one last challenge I was thinking of is that, where I currently live, sunlight is in much greater supply than water. We have multi-year droughts that make hydro-electric an unreliable energy source, and are currently threatened with water rationing. There are two parts to what I'm thinking here, and one of them leads to a weather question: 1) Off of our coast is a large supply of salt-water. Salt in the water changes its ability to conduct significantly, and thus, changes the characteristics of hydrolysis. It also gives us additional by-products to worry about, such as chlorine gas, or salt. That makes me question the feasibility of this, but suppose we find we can deal with this. Then 2) With the number of cars on the road, if we change emissions to water, then do we change the distribution of water vapor enough to actually cause changes in weather and/or vegetation? On this, I'm remembering an article I read some time back where it was asserted that another Dust Bowl in Oklahoma (the state where I was born) was highly unlikely because of the large number of reservoirs, and ponds that have been created in Oklahoma since that time. It was asserted that this changed the distribution of water, including water vapor, and caused the weather to change significantly so that Oklahoma now receives more rain than it did previously, and receives rain in times of the year that would not happen during dust-bowl years. Interesting thought, but I don't know if that is really well-founded. So summarizing my meandering thoughts: It looks like hydrogen cars are becoming a possibility for at significant part of the population in the US. I actually wouldn't mind making my next car one if a few challenges can be figured out. We could have a distributed model of fuel production (Actually, just energy storage) with hydrogen so that we can produce fuel at home with the very products that are pushed at us in every Best Buy. But suppose we get there, what effect does it have on our climate, local or wider? I'd just like to hear what other people think on the subject. I'm shooting from the hip here, having made no calculations. I did note the following from the web ... 14.6 billion gallons of gas consumed annually in California ... 10.8 trillion gallons of water consumed annually for irrigated agriculture in California ... gallons of gas is therefor 0.1% of gallons of irrigation water. I have no idea how many gallons of water would be required to extract the hydrogen equivalent of 1 gallon of gas. Irrigation does affect humidity. Ask any long time resident of Phoenix, AZ how the local humidity has changed over time. However, I think that the reservoir capacity of the lower troposphere is huge in comparison to what you are talking about. Let us know when you figure this out.
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Post by nautonnier on Oct 24, 2016 22:15:12 GMT
The AGW hypothesis is based on warming due to anthropogenic CO2 emissions causing an increase in water vapor and the water vapor increase is what causes the run away warming. Consequently, moving to a hydrogen 'economy' would 'cut out the middle man' and increase water vapor directly. Hence stll leading to AGW.
Of course the error in this hypothesis is that increasing water vapor while it does trap heat does so without raising temperature as it merely raises the enthalpy (heat capacity) of the atmosphere. What it does do is increase convection as water vapor is lighter than oxygen or Nitrogen, water vapor then condenses releasing heat into the upper atmosphere that radiates to space.
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Post by slh1234 on Oct 25, 2016 17:44:33 GMT
I know people always go back to the Hindenburg as a reason to not use Hydrogen, but we currently drive around with as much as 20 gallons of highly-flamable liquid in our cars, so we're not getting rid of risk by not going to hydrogen. I've read that it was the paint on the Hindenburg that we saw burning, but even so, there is no denying that Hydrogen is combustible. I just think that the risk is no greater than the risk we currently have with gasoline.
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Post by icefisher on Oct 25, 2016 18:06:47 GMT
Yeah if they propose I have a lighter than air balloon full of hydrogen in my trunk I am not on board.
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Post by nautonnier on Oct 25, 2016 21:16:33 GMT
The hydrogen in the lift bags of the Hidenberg all vented upward and was not a major part of the fire. The damaging fire was caused by the doped fabrics used in the construction.
Hydrogen is a lot safer than petroleum.
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Post by Ratty on Oct 25, 2016 21:48:10 GMT
I'm gonna work on a helium fuel cell, just to be safe.
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Post by slh1234 on Oct 26, 2016 4:19:03 GMT
Yeah if they propose I have a lighter than air balloon full of hydrogen in my trunk I am not on board. I'm not slamming nor criticizing, but I want to understand the thinking here because I hear this from more than just one person. We carry 16 gallons of gasoline in a car. Sometimes, we carry a tank of LPG in a car, taxi, forklift, or other equipment. We pump methane into our houses for heat and cooking. We put propane tanks on barbecue grills, or sometimes in large tanks outside of houses - especially rural houses. Why is hydrogen scarier than those things?
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Post by icefisher on Oct 26, 2016 5:05:21 GMT
Yeah if they propose I have a lighter than air balloon full of hydrogen in my trunk I am not on board. I'm not slamming nor criticizing, but I want to understand the thinking here because I hear this from more than just one person. We carry 16 gallons of gasoline in a car. Sometimes, we carry a tank of LPG in a car, taxi, forklift, or other equipment. We pump methane into our houses for heat and cooking. We put propane tanks on barbecue grills, or sometimes in large tanks outside of houses - especially rural houses. Why is hydrogen scarier than those things? i was being facetious. . . . .i would much less want to carry a gasoline balloon in my trunk. many years ago a boat i worked on carried extra fuel in foldable bladders on deck. one time a 750 gallon bladder burst and almost washed somebody overboard. at least it was diesel fuel and not gasoline.
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Post by Ratty on Oct 26, 2016 8:15:38 GMT
[ Snip ] ..... at least it was diesel fuel and not gasoline. Despite the higher flashpoint, that would not make me the slightest bit less apprehensive.
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Post by icefisher on Oct 26, 2016 21:43:16 GMT
[ Snip ] ..... at least it was diesel fuel and not gasoline. Despite the higher flashpoint, that would not make me the slightest bit less apprehensive. Nor did it for the owner/skipper. He bought a bigger boat with larger fuel capacity and greater range within a year.
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Post by sigurdur on Oct 26, 2016 23:47:36 GMT
I have no problems with Hydrogen.
However, Hydrogen has problems with metal. It bonds with it, making it very brittle. NDSU has been working for years, trying to find a hydrogen/diesel mix that doesn't cabbage out engines. Cat is one of the sponsors for this.
So far, everything goes well for about 800 hrs, and then valves break, cracks appear in the block.....etc. Ceramic seems to be the answer, but so far they haven't produced a ceramic valve/piston/ etc assmbly that can withstand the pressures over an extended run time.
Maybe some day? The hope was farmers could put up wind turbines and generate their own fuel.
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Post by neutrino on Oct 27, 2016 1:31:00 GMT
The following chart gives us some idea about the 'energy conversion' factor among some fuel types. www.afdc.energy.gov/fuels/fuel_comparison_chart.pdfHydrogen (H2) is a gas, and can be pressurized, but hard to liquify (got to go too low in temp; impractical to carry in your car). FYI, 6.66 “barrels of H2” per 1000 gallons of water. That is equivalent to a 7:1 H2 to crude oil ratio. (http://heshydrogen.com/hydrogen-fuel-cost-vs-gasoline/). Hydrogen, like any flammable material, will form explosive mixtures, just like gasoline. But it is a gas and can dissipate fairly fast. I would not feel very comfortable with a bottle of compressed hydrogen in my car. HOWEVER, fuel cells generate the hydrogen on the spot from (typically) water, using special catalysts (technology still far away from becoming a challenge to gas). When H2 burns, it gives water: 2 H2 + O2 --> 2 H2O + energy. Water will enter the water cycle and its concentration in the air is kept in check with the temperature (dew point). As a chemist, IMHO, fuel cells will / can substitute gas for fuel in cars, but will take a long time (20+ years). Catalyst efficiency will determine when this change will occur.
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Post by slh1234 on Oct 27, 2016 3:57:38 GMT
I have no problems with Hydrogen. However, Hydrogen has problems with metal. It bonds with it, making it very brittle. NDSU has been working for years, trying to find a hydrogen/diesel mix that doesn't cabbage out engines. Cat is one of the sponsors for this. So far, everything goes well for about 800 hrs, and then valves break, cracks appear in the block.....etc. Ceramic seems to be the answer, but so far they haven't produced a ceramic valve/piston/ etc assmbly that can withstand the pressures over an extended run time. Maybe some day? The hope was farmers could put up wind turbines and generate their own fuel. There are a couple of things I'm thinking about as I read this, Sig. The first one is that there is more than one type of hydrogen engine. I think what you are talking about is the internal combustion hydrogen engine. It has been experimented with, and I think you're right about one of its biggest weaknesses. I'm thinking primarily about hydrogen fuel cells. That's very different. It's also possible to line the storage and delivery systems with substances that don't react so readily with hydrogen, and so metals don't touch the hydrogen, except in the internals of the power cell where metals may catylize the power-producing reactions. Am I right in understanding what you're talking about?
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Post by slh1234 on Oct 27, 2016 4:07:10 GMT
The following chart gives us some idea about the 'energy conversion' factor among some fuel types. www.afdc.energy.gov/fuels/fuel_comparison_chart.pdfHydrogen (H2) is a gas, and can be pressurized, but hard to liquify (got to go too low in temp; impractical to carry in your car). FYI, 6.66 “barrels of H2” per 1000 gallons of water. That is equivalent to a 7:1 H2 to crude oil ratio. (http://heshydrogen.com/hydrogen-fuel-cost-vs-gasoline/). Hydrogen, like any flammable material, will form explosive mixtures, just like gasoline. But it is a gas and can dissipate fairly fast. I would not feel very comfortable with a bottle of compressed hydrogen in my car. HOWEVER, fuel cells generate the hydrogen on the spot from (typically) water, using special catalysts (technology still far away from becoming a challenge to gas). When H2 burns, it gives water: 2 H2 + O2 --> 2 H2O + energy. Water will enter the water cycle and its concentration in the air is kept in check with the temperature (dew point). As a chemist, IMHO, fuel cells will / can substitute gas for fuel in cars, but will take a long time (20+ years). Catalyst efficiency will determine when this change will occur. Very interesting. I'm still going over your chart and trying to put it together. (It would have helped had I started before I had a glass of wine this evening ) I'm very interested in a chemist's perspective on this. However; the cars such as the Marai are running on hydrogen currently. They're not producing the hydrogen on the spot, though - they're using the compressed hydrogen as you astutely pointed out. So I'd really like to get your thought on the distributed production of hydrogen like I was talking about - many of us in CA have solar panels on our roofs, and every Best Buy is filled with people trying to sell solar panels. I'm not sure it helps with the power grid since we can't shut down power production plants as a result of solar panels because we might have a cloudy day, for instance. (Rare in this part of CA, but it still happens). But using the solar power to hydrolize water into hydrogen, which is then just a way of storing the energy, seems like it can actually produce fuel for cars, and maybe even electricity for our homes on cloudy days, thus allowing us to actually shut down coal fired power plants. I'm just thinking out loud, but I'd love to have expert commentary on the thoughts. (If nothing else, it gets me away from the noise of politics right now ) Edit: Even in the best scenario I can envision right now, we would still have to have some type of hydrocarbon fuel for things like jet engines, for example. I'm just thinking through where other fuel types may have application. I'm a software engineer/architect, and not a chemist or physicist, so I know I'm out of my day job and into my hobby. I'm also not a warmist, but I do like to think of other possibilities for fuel, and re-use of energy.
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