Fresh water vs hydrogen power generation

SpaceNut · 2022-06-12 14:40:03

This nation started out with using the fresh water captured in reservoirs that allowed for power generation many 100's of years in the past

Fast forward to drought caused forecast changes in agriculture, along with a need to still create power all while still needing fresh water.

Here is the drought stricken area
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I got thinking about the electrolysis video I posted that was used to feed fuel to a power generator and wondered how much water was used for a given level of power being created. Then I wondered about how much water was falling in a power generation plant to make the power we used again to compare those 2 levels of water that would be used.

If power generators used less water to create the same level of power we would gain a level of water for other uses if we made a commercial product that was safe and not all that expensive to own.

The first thing for the water is to stop using it to produce power but that is easier said than done with no one wanting to use nuclear and carbon based is causing the effect to which is driving the drought in the first place. That leaves bringing in solar to the public and not just to the power companies as the means to get off from using water to generate the power we are using. Pumping any water from any source runs into this very problem at its starting point to bringing it to a site via pipelines whether its processed or not.

I have been searching for the amount of water that is used to create power and whether if you used the water to make hydrogen that you would use less water to create the power which is needed.

https://www.ucsusa.org/sites/default/fi … plants.pdf
Freshwater Use by U.S. Power Plants Electricity’s thirst for a Precious resource

https://www3.epa.gov/region1/npdes/merr … R-1501.pdf

https://www.nrel.gov/docs/fy04osti/33905.pdf
Consumptive Water Use for U.S. Power Production

https://greet.es.anl.gov/files/water-hydro
“Analysis of Water Consumption Associated with Hydroelectric Power Generation in the United States”

Since we know the output of a fuel cell is water we can still use it more than once.

I am looking at if water was broken down to use to generate power in a generator or fuel cell as to whether or not the amount would be a savings of water for the same levels of power required for the customer as the exhaust is water that can be reclaimed for drinking.

https://www.ge.com/content/dam/gepower/ … ration.pdf
POWER TO GAS: HYDROGEN FOR POWER GENERATION
Fuel Flexible Gas Turbines as Enablers for a Low or Reduced Carbon Energy Ecosystem

Data for the dam

http://gcdamp.com/index.php?title=HYDROPOWER

Glen Canyon Dam is the second highest (710 feet) concrete-arch dam in the United States, second only to Hoover Dam which stands at 726 feet. The 26.2 million acre-feet of water storage capacity in Lake Powell, created by Glen Canyon Dam, serves as a ‘bank account’ of water that is drawn on in times of drought. This stored water has made it possible to successfully weather extended dry periods by sustaining the needs of cities, industries, and agriculture throughout the West.
Hydroelectric power produced by the dam’s eight generators helps meet the electrical needs of the West’s rapidly growing population. With a total capacity of 1,320 megawatts, Glen Canyon Powerplant produces around five billion kilowatt-hours of hydroelectric power annually which is distributed by the Western Area Power Administration to Wyoming, Utah, Colorado, New Mexico, Arizona, Nevada, and Nebraska.

https://en.wikipedia.org/wiki/Glen_Canyon_Dam

Because of fluctuating demands on the electrical grid, the dam release into the Colorado River rises and falls dramatically on a daily basis. After the dam was completed in 1964, there were few restrictions on hydro-power generation. The minimum dam release was set at a meager 1,000 cubic feet per second (28 m3/s) (increased to 3,000 cubic feet per second (85 m3/s) during the summer whitewater rafting season), with a maximum of 31,500 cubic feet per second (890 m3/s) during peak times; to respond to changing power demands, river flows could double or even triple in the space of an hour.
The EIS completed March 21, 1995 cemented some restrictions on dam operations, limiting the maximum power release to 25,000 cubic feet per second (710 m3/s), the maximum hourly "ramp-up" (increase in river flow) to 4,000 cubic feet per second (110 m3/s), and the maximum "ramp-down" to 1,500 cubic feet per second (42 m3/s).[137] The minimum dam release was set to 8,000 cubic feet per second (230 m3/s) during the day and 5,000 cubic feet per second (140 m3/s) at night. Flood control releases are allowed to go higher, but must remain constant for the entire month
Between 1980 and 2013, Glen Canyon Dam generated an average of 4,717 gigawatt hours (GWh) per year, enough for about 400,000 homes. The highest was 8,703 GWh in 1984, and the lowest was 3,299 GWh in 2005.

https://www.glencanyon.org/wp-content/u … w-Full.pdf

https://www.usbr.gov/uc/rm/crsp/gc/

The powerplant, consisting of eight hydroelectric generating units with a combined capacity of 1,320 megawatts, is a significant part of the CRSP power resources with 79 percent of the total CRSP capacity.
It would take 2.5 million tons of coal or 11 million barrels of oil each year to generate the same amount of power (based upon an approximate conversion rate of 580 kilowatt-hours per barrel of oil and 1,822 kilowatt-hours per ton of coal).

It is still hard to pin down the water rates to make the turbines power.

I am hoping that kbd512 or calliban does stop by to think about this question and its answer.

SpaceNut · 2022-06-12 14:43:08

49% of hydropower capacity is owned by the U.S. government, federal dams represent a big opportunity to develop non-powered dams. five%20water.jpg?itok=8VAh61ey

How much hydropower power could I generate from a hydro turbine?

maximum hydropower power output is entirely dependent on how much head and flow is available at the site, so a tiny micro-hydro system might produce just 2 kW, whereas a large utility-scale hydro system could easily produce hundreds of Megawatts (MW).
If you don’t mind equations the easiest way to explain how much power you could generate is to look at the equation for calculating hydropower:
P = m x g x Hnet x η
Where:
P
power, measured in Watts (W).
m
mass flow rate in kg/s (numerically the same as the flow rate in litres/second because 1 litre of water weighs 1 kg)
g
the gravitational constant, which is 9.81m/s2
Hnet
the net head. This is the gross head physically measured at the site, less any head losses. To keep things simple head losses can be assumed to be 10%, so Hnet=Hgross x 0.9
η
the product of all of the component efficiencies, which are normally the turbine, drive system and generator
For a typical small hydro system the turbine efficiency would be 85%, drive efficiency 95% and generator efficiency 93%,

https://dothemath.ucsd.edu/2011/12/how- … an-we-get/

Hydroelectric dams exploit storage of gravitational potential energy. A mass, m, raised a height, h against gravity, g = 10 m/s², is given a potential energy E = mgh. The result will be in Joules if the input is expressed in meters, kilograms, and seconds (MKS, or SI units). Water has a density of ρ = 1000 kg/m³, so if we know how many cubic meters of water flow through the dam each second (F), the power available to the dam will be P = ηρFgh. We have inserted η to represent the efficiency of the dam—usually around 90% (η≈0.90).
The height of the water behind the dam is the relevant height for the potential energy calculation, even if a given parcel of water is collected at the bottom of the dam. This is because the pressure of the water above provides the motive force. In the absence of turbines or other restrictions, the water would emerge from the penstock at a velocity of v = sqrt(2gh) so that a flow, F, would require an area A = F/v. For example, Hoover Dam, at 222 m high (in the days when Lake Mead was full!) would eject water at a stunning 67 m/s (150 m.p.h.) if a big hole opened up in the bottom. At the nominal flow rate of 1000 m³/s, this corresponds to a hole about 4 m in diameter
Some of the 10% inefficiency in hydroelectric dams is due to generator inefficiency, but some is because you can’t take all of the kinetic energy out of the water or it would stop flowing and stall the flow of the next batch. But nature is kind here, since kinetic energy goes as the square of the velocity. The velocity of the energy-sapped water is therefore sqrt(1 − η). So if we pull 96% of the energy out of the water, its flow velocity is 20% of the free-flow value (13 m/s in the foregoing example). Or we can grab 99% at a 10% exit speed (7 m/s, or 15 m.p.h.)

So there might be more fresh water if we use it for a more efficient power creation.

https://www.usbr.gov/power/edu/pamphlet.pdf

https://www.altenergymag.com/article/20 … tem/34924/

SpaceNut · 2022-06-12 16:08:45

things that we know about hydrogen

gather water and energy to break it bond into H + O of which the next step is to pressurize or condense to liquid.

If you are looking for hydrogen to be a savior a gallon of gas is equal to 1 kg of hydrogen and to get that you need to break down 2.64 gallons of water to obtain the equivalent in hydrogen as there is only 110 grams of it in a liter of water.
For earth that is not a problem as we use free air in the engines of choice but for mars we need to capture the oxygen for reuse.

It is also said that the electrolysis input to get the hydrogen is just 70% efficient.

https://www.energy.gov/eere/fuelcells/h … ectrolysis

Solid oxide electrolyzers must operate at temperatures high enough for the solid oxide membranes to function properly (about 700°–800°C, compared to PEM electrolyzers, which operate at 70°–90°C, and commercial alkaline electrolyzers, which typically operate at less than 100°C). Advanced lab-scale solid oxide electrolyzers based on proton-conducting ceramic electrolytes are showing promise for lowering the operating temperature to 500°–600°C. The solid oxide electrolyzers can effectively use heat available at these elevated temperatures (from various sources, including nuclear energy) to decrease the amount of electrical energy needed to produce hydrogen from water.

The electrolysis process uses between 40-50kWh to generate 1 kg of hydrogen. So, using the lower end of that range, the electric power required for 250 kg of H2 is about 10 mWh, which, when scaled up to the full launch amount, is about 10000mWh, or roughly 415 mw of generating capacity working 24 hrs a day is required to supply the hydrogen for a single launch.

This ‘brine electrolyzer’ can mine oxygen, hydrogen from water on Mars origin-86.jpg?lb=1536,864

a256b9_3b8e2a4f8b3d493fa3f3b89fca5f3eae~mv2.webp

To satisfy those same oxygen requirements, the cell active area of the 2.2V brine electrolyzer is .375m and 1.2m^2 respectively.

Synthetic fuels do need to catch on for sure.

I was wondering about the water electrolysis with flash back chamber for direct feed into a generator as to how much water is required for a given power output to be used.

https://youtu.be/qdDoxQEwMxU
For diesel

kbd512 wrote:

If we electrolyze Hydrogen using Hysata's water electrolysis cell, then we would need 5,602.5TWh of input electrical power per year, at 41.5kWh/kg of H2, to produce 135 billion kg of Hydrogen for the 135 billion gallons of gasoline we consume each year. That's equivalent to about 640 1GWe nuclear reactors running at maximum capacity, all year long. Something tells me we'd have a hard time managing that, though I will freely admit that the input material requirements are bound to be much lower for nuclear power.

this contains the 4 type and temperature pg 32
https://irena.org/-/media/Files/IRENA/A … t_2020.pdf

Cummins How to build an electrolyser

SpaceNut · 2022-06-12 16:10:43

Also if we make long chains we can also use them
propane generators are basically the same generator just with a different fuel being delivered to it with electric power being the output from its use. Of course the size of the power output relates to the consumption rates for doing so. Most generators can not run continuous as well. All engine seem to have these flaws....
https://www.generatorhero.com/how-much- … rator-use/

Home Generator sizes, a 22 KW Generac generator would consume 5.9 cubic meters per hour of natural gas which is similar to propane in use.

Can we ever get information without needing to convert it....

https://preparednessadvice.com/propane- … st-choice/

Propane produces 92,000 BTUs per gallon, gasoline is capable of producing 114,000 BTUs per gallon, and diesel is capable of producing 129,500 BTUs per gallon. This means that it will take more propane per hour that either gasoline or diesel to run a generator.
Propane is a gas that is stored in liquid form. When the tank reaches a certain pressure, the propane turns to gas and dispenses from the tank. The pressure in the tank is measured in pounds per square inch (psi).
On average, a generator uses 2 to 3 pounds of propane per hour. However, this amount can vary depending on the size of the generator and how high the wattage is.

So it appears that liquid fuels are the way to go but for how long as the price continues upward.

propane is stored in a pressurized tank which takes energy to do.
https://www.wtamu.edu/~cbaird/sq/2013/0 … as-is-not/

https://afdc.energy.gov/fuels/propane_basics.html

https://uwaterloo.ca/chem13-news-magazi … fuel-gases

of course if we are direct using the fuel it might not need a lot of energy to make it usable.

tahanson43206 · 2022-06-12 17:05:51

For SpaceNut ...

The video at this link is about a way of making hydrogen that is slightly? more cost effective than traditional methods.

https://www.youtube.com/watch?v=2XhsQ7nuoRo

This Hydrogen Breakthrough Could DISRUPT The Whole Energy Industry!!
87,584 views Jun 9, 2022 Covering the topics of Hydrogen Breakthrough, Green Hydrogen, Hysata Hydrogen Electroliser System, Energy Industry, and more!…

If you have time, please see if you can tell if this method is an improvement or not. I ** think ** the developers are trying to deal with what (I gather) is a normal problem in hydrogen electrolysis.

In any case, you have a supply of water that is (comparatively) "free" from Ma Nature (if you pay for electricity to pump it from underground), and you have a supply of << koff koff >> "free" solar energy (if you can harness is) so ** theoretically ** you could make hydrogen at home.

If you were to do that, then the topic might be revised to show: Fresh water ** and ** hydrogen power generation.

(th)

SpaceNut · 2022-06-12 20:02:12

If you are making water, you are doing the reverse of electrolysis with a fuel cell while it makes power.

According to the U.S. Department of Energy, fuel cells are generally between 40 and 60% energy efficient. This is higher than some other systems for energy generation. For example, the typical internal combustion engine of a car is about 25% energy efficient
The fuel cell thermodynamic efficiency is given by the ratio of the Gibbs function change to the Enthalpy change in the overall cell reaction. The Gibbs function change measures the electrical work and the enthalpy change is a measure of the heating value of the fuel.

https://www.energy.gov/sites/prod/files … _sheet.pdf

though there is 5 types they all fall with in the range earlier posted.

https://www.californiahydrogen.org/wp-c … tsheet.pdf

So to split water into its elements you get 70% of the energy you put in to do so and a return by fuel cell later of just 50% possibly.

What we know is the energy is lost as heat in both.

https://pubs.acs.org/doi/10.1021/acsenergylett.1c01375
Does the Green Hydrogen Economy Have a Water Problem?

https://asu.pure.elsevier.com/en/public … fuel-cells

it indicates you only get 85% of the water as an output which means the fuel cell has a gaseous level of oxygen and hydrogen that is unprocessed in the exhaust.

tahanson43206 · 2022-06-12 20:17:48

For SpaceNut re Post #6 ...

Thanks for the links and notes about efficiency around fuel cells.

This is the first time I've encountered the observation that only 85% of input chemicals are converted to water. Hydrogen in the free atmosphere wouldn't do any harm, and the atmosphere already contains oxygen, so there is no pollution. Still, it is disappointing that the hydrogen is not fully consumed.

In thinking about the problem further, the oxygen not converted came from the atmosphere, so it just returns there.

I'm wondering what part of the hydrogen is lost. Hopefully the link you provided will contain that detail.

I bring this up because i don't see why chemicals not consumed on the first pass cannot simply be fed back to the input.

(th)

SpaceNut · 2022-06-12 21:40:18

I got a bit of a shock when I googled "how much water is needed to make gasoline"

To complete all the steps required to produce a gallon of gasoline takes, on average, three to six gallons of water.

https://www.answers.com/Q/How_much_wate … f_gasoline

1851 gallons of water to refine a barrel of crude oil. One barrel of crude oil produces 19 gallons of gasoline and 10 gallons of diesel fuel, in this respect it takes 97 gallons of water to produce a gallon of gasoline.
If you combine gasoline and diesel, it takes 63 gallons of water to produce a gallon of "fuel." A total of 42 gallons of petroleum products are produced from a barrel of crude oil, in this respect it takes 44 gallons of water to produce each gallon.

Ouch for how much water use

tahanson43206 · 2022-06-12 22:01:47

For SpaceNut re #8

My first reaction is that this post of yours is impactful. However, it might help if you were able (and I don't know if it is possible) to differentiate between the processes to "refine" gasoline from crude oil, and to make gasoline from water and air as kbd512 is proposing, and Calliban long before.

If we are making gasoline from ** sea ** water, then it seems to me the consumption of fresh water is zero.

(th)

SpaceNut · 2022-06-13 19:24:06

The gasoline and diesel are reference for how much water comparison since we have the sea water to fresh value that is 1.8 cu meter to yield just 1 cubic meter that is fresh. Since we have not a baseline for conversion of sea water to complete long chain hydrocarbons yet. At that point its the same as the conversion of water to a usable product efficiency or required input energy to achieve the goal. We must use the same energy input for any path taken to get good comparisons.
I still need to find a comparison of fuel type change to efficiencies for ICE engines that have a generator connect to it since we have the fuel comparison.

tahanson43206 · 2022-06-13 19:51:50

For SpaceNut ...

From post #1:

I have been searching for the amount of water that is used to create power and whether if you used the water to make hydrogen that you would use less water to create the power which is needed.

It seems to me (subject to correction as we learn more) that there must be books (if not libraries full) on how to design a hydropower plant.

Such documentation would surely document exactly how much water flow is needed to generate a given amount of power using a given turbine with a given generator.

I would also expect to find that over the decades, the performance of hydroelectric systems has improved so that any further improvement would cost an enormous amount and yield only a tiny improvement.

My guess (and that's all it is right now) is that hydroelectric power stations are among the most efficient power generating devices known to man.

The measurement should be fairly straight forward ....

You have a mass of water at elevation X. it descends to elevation y at some rate, and a measured amount of power is generated.

There should be tables upon tables of data from many decades of hydropower plant operation.

My guess is that if you use that power to make hydrogen, you are in effect storing energy in a chemical "battery".

The way that "battery" is used determines how efficient the power delivery phase might be.

The efficiency of hydrogen as an energy storage medium is independent of the efficiency of a hydroelectric power plant.

(th)

SpaceNut · 2022-06-14 19:08:03

post 2 contains the equations but not the specific dam and equipment that might have in efficiencies due to age.

That answer for your area needs to show using a quantity for energy creation that is not kinetic in creation aka gravity storage.

Of which even working from the exhaust side of the fuel cell for the daily need what would we need for a customers site to send hydrogen to in order to create the water at the end use and to provide its power.

That answer is part of post 3 but design all tart from whats the water source and original power to get this process going.

That source for your area can come from solar in several formats and still get that hydrogen for use.

so many variables are present that still need to be sorted out in order to prove which has used to much water.

kbd512 · 2022-06-15 00:12:32

SpaceNut,

Regarding the question in your original post, a simple exergy destruction analysis will illustrate that you always lose energy when transforming energy from whatever source, into some other form. Even if you store electrical energy in a battery, you are still losing some of that energy in the process. The very act of transforming moving water into electricity involves some measure of inefficiency. In other words, the total kinetic energy associated with a moving volume of water is greater than the total amount of electricity after the energy transformation. Dams are over 90% efficient at converting kinetic energy from moving water into electrical energy. Vanishingly few electric-to-fuel or thermal-to-fuel processes are "as efficient", even though that is seldom "the point" of producing stored energy. Almost by definition, any energy conversion-for-storage mechanism is always less efficient that direct consumption as electricity. It just so happens that the Earth provides the moving water and some minor transformation of materials into machinery by skilled people can produce a hell of a lot of electrical power over a long period of time, so all the embodied energy invested into making the materials and machinery for the dam was "well worth it" over the decades that the dam will operate.

Exergy destruction measures the efficiency of the transformation of energy in one form to some other form. For example, maybe storing electricity from pumped hydroelectric power is 95% efficient. Converting hydroelectric power to chemical energy may be 50% efficient. Hysata claims their Hydrogen fuel cells are well over 90% efficient, but the fact of the matter is, if you directly consumed the electrical power from a turbine from a hydroelectric dam, then that's the most efficient "conversion" of moving matter (water), into some form of energy (electricity). If you want to know how efficient the electric-to-Hydrogen process would be, it's about 0.90 (moving water to electric) multiplied by Hysata's reverse fuel cell efficiency of 0.93976, which equates to an efficiency of about 84.58% efficient.

So... Even with a super-efficient reverse fuel cell, you still obtain more usable energy by directly pumping the electricity into the grid from the electric turbines embedded into the dam. However... There are also grid losses from electrical resistance in the transmission wiring and transformers, which amounts to 10% to 20% at most. If the utility would lose more electric power than that, then the electric utility operator will cease to run longer lengths of electrical power cables and will instead opt to produce electricity from another power plant closer to the point of consumption. This is what makes national or international scale electric power grids somewhat impractical to operate. How much power can you afford to lose by "shipping it" through thousands of kilometers of wiring?

If you already have all the electricity your customers need / want, then maybe additional production capacity is best devoted to storing the energy in the form of Hydrogen or some other type of fuel. Everything is a trade-off. There are no free lunches in engineering, only trade-offs, and all the additional equipment will cost a pretty penny, consume energy, etc, etc. The answer to which use is "most efficient" depends upon a lot of factors, but generally speaking direct consumption of electricity is most efficient. That doesn't mean that there aren't very good reasons to store or convert electrical or thermal power into liquid fuels. Basically, "storing" large amounts of electricity using current technology is highly impractical, but demand won't change to "fit" the pre-industrialization model of only consuming when you're producing, so it makes sense to store some power when you have an over-abundance of power. Some amount of storage for on-demand dispatch is always required for any practical grid.

Overall, I think liquid hydrocarbon fuels are currently the best answer to the energy storage problem if you maintain a closed-loop cycle that reuses exhaust gases to synthesize new liquid fuels. The 50% to 75% efficiency advantage of pure electrical systems doesn't make up for the orders of magnitude lower energy storage density of pure electrical energy storage systems, nor the fact that such electrical systems continuously degrade over fairly short periods of time.

A gasoline-powered engine will produce almost as much power 100,0000 miles later, after many thousands of start/stop cycles, as it did when it was brand new. Most of the time, any minor power losses from engine wear can be corrected by rebuilding the engine, which very seldomly means melting down all the metals in the engine and making a brand new engine. Rebuilding almost any sort of energy-dense modern battery means breaking down the entire battery into its base chemical components and then making a brand new batteries. In most cases, that requires even more input energy than starting from mined / "virgin" raw materials, which is why it wasn't done until mandated by governments, especially in the case of Lead-acid batteries. The bulk of the materials in a modern battery are packaging, power transmission, or thermal control.

I don't know how to dramatically alter the math on the energy input into batteries, and apparently nobody else does, either. What I do know is that the embodied energy sunk into all predominantly electrical or electronic machines is enormous, so ultimate durability and energy density in electrical energy storage systems are huge factors affecting their cost and utility for specific use cases. Until we figure out how to significantly alter the energy input math, I think simpler machines that use combustion engines of reasonable power output are the best answer. For whatever reason, the appliance and automotive industries want to sell everyone electronic gadgetry and race cars to ordinary people, rather than the simple / durable / reliable machines most people really need and want. I don't need a washing machine with 50 different wash cycle options. I don't need a 4,000 pound passenger car with 400 horsepower, either. Both are technically feasible using modern technology, but neither are practical if we consider their extreme cost, relatively short average lifespans, and the difficulty of recycling the materials they're made from into new machines with equal capabilities.

In my opinion, increasingly sophisticated technology is not a useful end unto itself. Any otherwise simple and purpose-built machine can be transformed into a fantastically complex gadget using enough electronics, but that doesn't mean the general utility of the machine was materially improved in many cases. Maybe there are more people than I'm aware of who are mesmerized by the sophistication of the gadgetry. I can't know everyone's reasons for buying "X" vs "Y". Virtually none of them are enamored with exorbitant repair bills. This begs the question of why every successive model of machine is more complex and more gadget-laden than the previous version. I know that the increasingly sophisticated machinery still sells, but is that due to the "whiz-bangery", or is it merely because that's what was on offer to the customer when he / she needed a new clothes washer or car or microwave oven?

Calliban · 2022-06-15 07:04:22

I really cannot see hydrogen catching on as either a static energy storage mechanism or a transportation fuel. Electrolysis plant is quite expensive. This makes it unsuitable for absorbing occasional bursts of excess energy from a wind turbine or solar farm. You need to run the plant heavily if you want capital margins to not dominate tge cost of the hydrogen. And for hydrogen to make any sense at all as a fuel, electricity would have to cheap. That is the opposite to how things are shaping up.

The properties of hydrogen also make it a weak contender as a synthetic fuel. At atmospheric pressure and room temperature, its density is 88 grams per cubic metre. The stuff barely exists! It's energy density is a meagre 10MJ per square metre. If you want to increase that energy density so that you can power a vehicle, say, then you have a tough job. You have to either compress that diffuse gas to hundreds of bars (which is close to behaving like an ideal gas at room temperature) or freeze it down to 20K, at which point in liquefies. Neither approach will work very well. At high pressure, a lot of energy is needed to achieve compression. Multi-stage intercooled, ATEX rated compressors will be needed. Hydrogen diffision through seals and metallic joints create an explosion and embrittlement problem. If you go the cryogenic route, the energy needed will be a sizable fraction of that contained in the hydrogen itself. Your fuel tank must be austenitic stainless steel. The tank and fuel lines must be heavily clad in impermeable insulation, otherwise air will liquefy on contact with cold surfaces. All things considered, one of least conevient fuel concepts imaginable.

Hydrogen could be produced using baseload electricity from dam or other powerplant and stored in gasometer tanks at close to atmospheric pressure. This is how coal gas, which is mostly hydrogen, was once stored. It could then be used to meet daily peak load power demands which a nuclear reactor wouod be unsuitable for. Better to store energy over a 24 hour period and then use a gas turbine to meet those peak loads. Hydrogen is not ideal for a GT, because its energy density is only 1/5th that of methane. So your GT will be downrated if run on hydrogen.

I can see electrolytic hydrogen having intermediate uses in situations where it doesn't need to be stored. We might use an electrolysis plant to supply hydrogen for ammonia synthesis. In places where natural gas is less available and nuclear energy is abundant, this may be an attractive option. This would preferably be direct feed from the plant into a steady-flow reactor of some kind. Likewise, hydrogen is already used for cracking heavy hydrocarbons and deoxygenating bio-oils to produce bunker fuels and middle distillates (diesel). We might well see those applications increase as light sweet crude becomes scarcer. Hydrogen could likewise be used to produce rough iron powder from iron oxide in an electrically heated furnace. The powder would then be converted to steel in a downstream electric arc furnace.

So we will never see a hydrogen economy as such. Hydrogen will probably be an intermediate reducing agent used in the production of other things.

I agree that the business model for cars is inline for a shake up. The number of cars produced globally, peaked several years ago. The average age of cars is increasing and the price of second hand vehicles is trending up. This does suggest that people are either less concerned with secondary embellishments on cars or increasingly unable to afford them. I suspect both. The idea of moving towards fully electric is a non-starter simply from a natural resource point of view. When one considers the extent of infrastructure needed for charging vehicles that most people cannot afford even now, it looks highly improbable that this burden will be sustainable in a future where most people will be poorer. Add onto that the additional costs imposed upon the electric grid and the BEV begins to look like a false start. Most likely, the most popular cars thirty years from now, will be small, lightweight petrol powered vehicles. Their speed and engine power will be limited compared to what most people use today. Some form of braking energy recovery will be used to reduce fuel consumption. The future looks less like Tesla and more like Fiat Panda. That is the sort of solution that will be affordable to people a couple of decades from now.

Last edited by Calliban (2022-06-15 07:20:04)

tahanson43206 · 2022-06-15 09:51:02

For SpaceNut .... congratulations for inspiring two thoughtful and detailed posts by kbd512 and Calliban.

SearchTerm:hydrogen evaluated by kbd512 and Calliban as an energy storage medium, and as a step in chemistry
SearchTerm:Ammonia Calliban makes observations about the potential of Ammonia as a hydrogen carrier

(th)

SpaceNut · 2022-06-15 19:03:21

Thank you both for the input which tells me that kbd512 conversion of sea water directly with solar concentrated heat is the way to go as its more important to keep the water behind the dams rather than creating power with it.
Along with Calliban suggestion that power electrolysis to gain hydrogen is also not the way to go.
That brings me to conclude that the solar concentrated thermal molten salt power systems is the better method for creation of power and not PV panels.

So making hydrogen with direct use in a generator to make power is a question to compare power of hydro dams as compared to its level of water it uses.

Calliban · 2022-06-15 20:29:44

SpaceNut wrote:

Thank you both for the input which tells me that kbd512 conversion of sea water directly with solar concentrated heat is the way to go as its more important to keep the water behind the dams rather than creating power with it.
Along with Calliban suggestion that power electrolysis to gain hydrogen is also not the way to go.
That brings me to conclude that the solar concentrated thermal molten salt power systems is the better method for creation of power and not PV panels.
So making hydrogen with direct use in a generator to make power is a question to compare power of hydro dams as compared to its level of water it uses.

SpaceNut, electrolysis may well be an acceptable option for producing hydrogen close to demand. If you don't have access to cheap natural gas and either don't have coal or are squeemish about using it, then electrolysis is really the only proven technology capable of producing hydrogen. But to be at all cost competitive with NG derived hydrogen, electricity must be cheap and available at high capacity factor. Hydro can do that. Nuclear can do that. Solar thermal with heat storage can (to an extent) do that. But wind and PV cannot. And operating an electrolsis plant at half capacity trashes its economics.

Hydrogen is in many ways the key to producing the cornerstones of civilisation. We can use it to produce rough iron, that can be upgraded into steel. We can use it to make nitrogen based fertilisers. We can use it to produce synthetic fuels and polymers. We can burn it to raise the temperatures neccesary for cement production. But it really isn't practical to store it in large quantities or for any significant period. Nor is it practical to attempt to pipe or ship it long distances. We should think of it as an intermediate product, that is made very close to where it is used and is made at the same rate at which it is being consumed. So what we would actually have is an electricity based economy, with hydrogen being an intermediate product used to make other thinfs that can be stored more easily.

Last edited by Calliban (2022-06-15 20:33:23)

SpaceNut · 2022-06-16 18:45:00

according to post 8 gasoline to hydrogen comparison the use of water is at a minimum a better choice to use the water directly with electrolysis feeding the engine on demand while venting at shut down of the engine into a temporary storage tank.
What I also would like to compare is the engines use as an electrical generator versus a dam power generator for that same water to power values of creation as that is I think is the solution to the drought area as it would save water to build up for future use.

Mars_B4_Moon · 2022-09-23 02:58:12

Hydropower Is Cheap, Clean, and Already Big. So Why's It In Danger of Drying Up?
https://www.esquire.com/news-politics/a … te-change/

Going big, and bigger-trend for China’s fuel cell stack
https://chinahydrogen.substack.com/p/go … for-chinas
Just in the first 9 month of 2022, a number of China’s fuel cell system producers have announced the debut of their 200 kw+ hydrogen fuel cell stack (single stack), and some companies have even notified their clients that bigger fuel cell stack (300 kw single stack) would be available by the end of 2022.

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