After many false starts, hydrogen power might now bear fruit
economist.com
economist.com
Hydrogen fuel cells are clean where you use them. But so are batteries. Inner cities could be kept cleaner using either. Inner city traffic is mostly short range, so batteries are at an advantage.
Batteries have a rare earth problem. But so do Hydrogen fuel cells. There is work to reduce it for both technologies.
Hydrogen fuel cells have a problem with varying loads. You would use additional batteries in cars to supply peak demand when accelerating or store braking energy. For comparable weight, range, and price you could replace all hydrogen technology with more batteries. Those bigger batteries would also wear out slower because the power demand per cell is lower.
So, when would hydrogen make sense? I think only if you don't care for efficiency. When you have so much electrical power that it costs you nothing and is available at least a few hours every night. Hydrogen would do well in a combination with large scale nuclear fission/fusion. It could take decades until we get there if we ever go that route.
I see that, as batteries become less and less expensive, the niche where Hydrogen could have good advantage is getting smaller and smaller. However you twist and turn it, either oil&gas or batteries have the advantage.
https://images.hgmsites.net/lrg/hydrogen-vs-electric--volksw...
This image (don't know the source), which includes oil and coal, is also a good visualization:
https://i.imgur.com/Wuhnlvu.png
Even simpler:
In other words, if a refueling station can do solar or wind capture and electrolysis on-site, the economics are better. This would be unlikely for stations in urban or high-density areas, but for rural and suburban locations it might be a win.
Say a fueling station needs to serve (only) 100 cars per day, providing 50kWh per car. That's 200kW average generation power needed. Ballpark, a 1 m2 solar panel can generate 200kWh/year, or 23W average. (quora answer, 2018). You need .. really? 9100 m2 of area, which is .91 hectare or 2.25 US acres.
A 200kW per day (73000kWh/year) wind turbine might stand 25m tall. (uk wind energy report, 2014) Will these function in suburban to urban settings? Would they be accepted by the public? In the US, siting rules are a mess, but one example I found called for 2500 feet (760+m) distance to property line and 1.5 times turbine height to overhead utility lines. (NCSL, 2016)
Given these fairly large size requirements, unless I slipped some decimal points, it doesn't seem likely to work out.
https://www.quora.com/How-many-kWh-will-1-sq-meter-of-solar-...
https://cdn.ymaws.com/www.renewableuk.com/resource/resmgr/Do...
https://www.ncsl.org/research/energy/state-wind-energy-sitin...
The only thing that beats oil is nuclear fission. With everything else, production takes up land that could be used for something else, or isn't being used for something else because it has problems such as distance or inhospitable climate or unfriendly (steep or unstable) terrain. All of which drive up maintenance costs or make the land also unusable for energy production.
There are no good solutions apart from the one that coal companies astroturfed us into nearly banning in the 1960s.
I understand the impulse to defend nuclear power against seemingly irrational criticism, but that shouldn't distract you from the incredible advances that other technologies have been making. Nuclear has had its time, and today it's just not a competitive way of making electricity anymore.
Beside, you're never going to convince people that nuclear is perfectly safe - it just isn't. Even if you can completely rule out catastrophic failure, you still have a bunch of people who need to go to work every day and work with radioactive materials. Yes, it can be done safely, but personally I'm happy I don't have to (and I do work with other toxic crap in the lab on a regular basis ;)).
So, at the end of the day, you're going to need to make an argument that goes like "... but nuclear power is worth it because we have no better alternatives" at some point. But look at this report on levelized cost of energy (LCOE) [0]. Wind and solar are absurdly cheap! We need to focus on solving the intermittent supply issue now, and that looks to be totally doable, if expensive, with current technology. But it's only getting cheaper (see literature I've cited in a different post in this thread).
Of course, calculations might change if there's some sort of technology breakthrough in nuclear technology - as in any technology.
Are the economics better than just placing that solar or wind plant on the grid and using electricity for battery-powered cars? You still have big losses in electrolysis, compression and then power generation in a fuel cell.
AKA Germany would probably be better off investing solar farms in southern Spain and connecting via long distance transmission lines. Only 1600km or so. Also consider sunset is an hour later in south west Spain.
Nuclear is not cheap compared to photovoltaics, wind and hydro. Since the former two are bursty, overcapacity in them leads to cheap excess energy at times, which needs to be stored.
Which storage method is the best depends on multiple factors, particularly on the duration of storage, capacity required and frequency of charging/discharging.
Batteries are great for relatively short term storage, but for long term, seasonal storage, hydrogen and pumped hydro are the options we have. Pumped hydro capacity is limited, and the cost of hydrogen production and storage is coming down. So that's where hydrogen makes sense: Long term, high capacity storage.
Not necessarily, at least not always. It needs to be used and this can be made possible by expanding the high voltage networks.
This would be especially effective in the east-west direction because then areas with sun could supply areas where it is dark. This reduces the need for storage while also making the system more robust.
If we add more north-south interconnects we can use some of the Scandinavian hydro plants as batteries (I agree that pumped storage can never be as extensive as one would like and is not as easily achieved as some people think) and North Africa for solar power.
What is most lacking is not new technology but political will to interconnect the electrical supply network so that energy can flow more easily from where it is produced to where it is needed.
I think many people see excess capacity as a form of waste to be reduced, but it's like thinking that gigabit fiber is a waste because it's not used to it's full capacity. The value of oversupply is that it's always available when you need it. The fact that new industries can spawn from the super cheap rates for excess electricity or data is just a bonus.
I disagree, especially at high latitudes. Try that in the UK, for example, at https://model.energy/
https://www.forbes.com/sites/christopherhelman/2020/05/21/ho...
Go play with this web site and look at the optimal solutions (for producing constant power output) under various cost assumptions, using real weather data.
Generally, the best solutions involve some overbuilding, some storage, and some combination of solar and wind. For sunny places, solar + batteries (+ a little hydrogen); for windy places, wind + hydrogen (+ a little solar and batteries).
The amount of energy storage required even to just handle the daily duck curve is staggering. To put this in perspective, the US consumed 11.5TWh of electricity daily. Global lithium ion battery production is 300GWh per year.
Until some truly groundbreaking storage mechanism gets developed, renewables have difficulty providing more than 40-50% of energy demand.
I really wish that I was wrong instead of just semi-accurate and sloppy.
> Nuclear is not cheap compared to photovoltaics, wind and hydro.
The price of nuclear power is dominated by regulation. Running the power plant is quite cheap. The real cost is satisfying regulation and getting rid of the nuclear waste. If you use new reactor designs it promises to be really cheap. But currently regulation cost is so high that it's not happening any time soon. Similarly, nuclear fusion promises a lot. Maybe one day it will deliver.
My point is that IFF you have dirt cheap nuclear energy, it would be quite appealing to convert it to hydrogen (or Methane/Methanol) and to replace natural gas and oil with it. But since that is not happening, renewables will NOT deliver enough energy to replace gas and oil completely any time soon. We have a factor of 10-100 to scale up for that to happen.
> Since the former two are bursty, overcapacity in them leads to cheap excess energy at times, which needs to be stored.
Wind and solar currently rarely have overcapacity because in many nations mandated by regulations the other sources will have to go offline instead. The problem is that if you really manage to build up wind and hydro to satisfy electricity demand on average the Hydrogen generators will only utilize somewhat in the region of 10% of their design capacity in average. They need to be very cheap to run at a profit for that.
Also, if electricity is really cheap, we have a lot of uses for it. For example heating is ideally done using clean electricity. This substitution frees up a lot oil and gas that you can use instead of Hydrogen.
> Which storage method is the best depends on multiple factors, particularly on the duration of storage, capacity required and frequency of charging/discharging.
> Batteries are great for relatively short term storage, but for long term, seasonal storage, hydrogen and pumped hydro are the options we have. Pumped hydro capacity is limited, and the cost of hydrogen production and storage is coming down. So that's where hydrogen makes sense: Long term, high capacity storage.
True. But if you have enough production capacity, you don't really need storage. You only store it if it is cheaper than simply generating more power when you need it. Instead of generating Hydrogen and storing it you could use a natural gas peaker plant. You have natural gas and storage solutions already available and installed. Hydrogen has to be cheaper than natural gas.
You have some nice academic references while I only have anecdata that may be partially outdated by now. In my past experience Hydrogen and fuel cells have failed to deliver time after time, year after year while Lithium batteries have really taken off.
Look at that figure: https://ars.els-cdn.com/content/image/1-s2.0-S25424351183058...
Currently, Hydrogen is off the charts because it is too expensive but it is projected to come down and dominate the upper end in 30 years while Lithium batteries dominate all the rest. Lithium batteries are here today and the focus is on batteries. Natrium and other battery technologies may be ready by then and drop prices a further factor of 10.
I do not deny that some Hydrogen from electricity makes sense. Especially if you need Hydrogen for your chemical processes. Maybe even for storage of excess electricity (or just adding it to the natural gas instead of storing it). But I don't see Hydrogen for small vehicles anytime soon.
Can you tell me which nuclear stations cover all their own costs?
As far as I am aware, all nuclear power stations in the world do not bear that cost - it is always picked up by the government.
They often figure that the long term cost is worth it for energy stability - not because nuclear is cheap - but because it is more stable than relying on energy imports from another country.
The notion that cost of storing nuclear waste would make nuclear power considerably more expensive is incorrect.
1. https://www.energy.gov/ne/articles/5-fast-facts-about-spent-...
2. https://en.m.wikipedia.org/wiki/Yucca_Mountain_nuclear_waste...
I really want renewables to work but so far grid scale batteries just don't exist. The biggest lithium battery isn't even a blip, it's roughly equivalent to what the UK receives through French over production every 6 minutes.
Then how come that not a single country has yet developed a method for storing their nuclear waste safely and permanently?
From your first link:
> The fuel is either enclosed in steel-lined concrete pools of water or in steel and concrete containers, known as dry storage casks.
> For the foreseeable future, the fuel can safely stay at these facilities until a permanent disposal solution is determined by the federal government.
But from Wikipedia's page on dry cask storage, linked from your second link:
> In the 1990s, the NRC had to “take repeated actions to address defective welds on dry casks that led to cracks and quality assurance problems; helium had leaked into some casks, increasing temperatures and causing accelerated fuel corrosion”.
> With the zeroing of the budget for Yucca Mountain nuclear waste repository in Nevada, more nuclear waste is being loaded into sealed metal casks filled with inert gas. Many of these casks will be stored in coastal or lakeside regions where a salt air environment exists, and the Massachusetts Institute of Technology is studying how such dry casks perform in salt environments. Some hope that the casks can be used for 100 years, but cracking related to corrosion could occur in 30 years or less.
In other words the "safe" temporary storage is not really safe.
From your second link:
> In September 2007, it was discovered that the Bow Ridge fault line ran underneath the facility, hundreds of feet east of where it was originally thought to be located, beneath a storage pad where spent radioactive fuel canisters would be cooled before being sealed in a maze of tunnels. The discovery required several structures to be moved several hundred feet further to the east, and drew criticism from Robert R. Loux, then head of the Nevada Agency for Nuclear Projects, who argues that Yucca administrators should have known about the fault line's location years prior, and called the movement of the structures "just-in-time engineering."[80][81] In June 2008, a major nuclear equipment supplier, Holtec International, criticized the Department of Energy's safety plan for handling containers of radioactive waste before they are buried at the proposed Yucca Mountain dump. The concern is that, in an earthquake, the unanchored casks of nuclear waste material awaiting burial at Yucca Mountain could be sent into a "chaotic melee of bouncing and rolling juggernauts".[82]
How sure can we be there are no other fault lines waiting to be found? How sure can we be earthquakes won't cause problems in 100 years, or 500 or 5000 years? The Yucca Mountain repository is supposed to last 10000 years. How do we know it will?
Storing nuclear waste is a huge unsolved problem. What's going to happen is that we're going to put it somewhere out of sight and let future generations deal with it. As other posters said: the nuclear industry externalizes all its difficulties to government, society and even future generations.
They have. Finland has built a disposal site: https://en.m.wikipedia.org/wiki/Onkalo_spent_nuclear_fuel_re...
The US built the Yucca Mountain, but then Congress blocked its usage. This was done due to political posturing not technical concerns. Burying it in an area with no groundwater is a foolproof method of disposal short of hyperbolic scenarios involving societal collapse followed by a future people digging in an area with no resources for an inexplicable reason. Yucca mountain is not in a geologically active area, so the concern about earthquakes is moot.
> How sure can we be there are no other fault lines waiting to be found? How sure can we be earthquakes won't cause problems in 100 years, or 500 or 5000 years? The Yucca Mountain repository is supposed to last 10000 years. How do we know it will?
After 10,000 years the uranium is no more radioactive than it was when it was dug out of the ground. And when Yucca mountain is filled the entrances are blocked by meters of concrete - even if canisters are somehow get compromised the uranium still needs to magically get through several meters of rock and concrete to get out into the environment.
It is a solved problem, but politicians have decided not to use the solution. In the US that is, Europe has it's dig in Finland continuing as planned.
This thread is being rate limited, reply in edit:
Understand the the "controversies" section on Wikipedia includes concerns that are addressed. In fact you even quoted the explanation that tectonic deformation is not a concern.
And if it does get into the groundwater it will be detected. Do you realize that Uranium is a naturally occurring element? It's a contamination concern even where there is no waste disposal: https://www.sciencedaily.com/releases/2015/07/150716094840.h...
We're acting like uranium is some magic kryptonite, when it's 40 times as common as gold. We know how to detect uranium in water, because naturally occurring uranium gets in it.
> In other words the "safe" temporary storage is not really safe.
I think you misunderstood this paragraph. The waste is being stored in these temporary casks because the Yucca Mountain facility's budget was eliminated, and thus temporary storage is the only storage option.
I think people tend to be too blinded in their focus on cars here? I don’t think hydrogen cars make much sense. Batteries all the way – but that doesn’t mean that hydrogen is without merit for other applications.
And if you want to replace all greenhouse gases in industrial applications with green hydrogen you still need a shitton of hydrogen (since, yeah, it’s inefficient – but if it’s the most efficient greenhouse-neutral way to get there – what choice is there?), so that’s not something you can just improvise. You need to tackle it head-on.
That’s why I fear people being stubbornly focused on cars. Even if not a single car will ever use hydrogen ever we could still need a lot of green hydrogen for other purposes if we want to be greenhouse-neutra.
https://fuelcellsworks.com/news/a-simplified-way-to-turn-foo...
First: Energy density The primary advantage of hydrogen is energy density. Though Li Ion and other technologies have improved considerably, they are no where near the energy density of fossil fuel technologies and therefore vehicles which use these batteries will have to carry huge weight of batteries to get better range. With Hydrogen that is not a problem.
Second: Storage There has been huge advances in the safe storage of hydrogen - from the use of nanoporous carbon for storage https://www.sciencedirect.com/science/article/pii/S100200711...
to the use of LOHCs (Liquid Organic Hydrogen Carriers) that is aromatic liquids to store hydrogen instead of storing it as gas or liquid hydrogen: https://www.chemistryworld.com/features/hydrogen-storage-get...
Simply, it is by far the best of all possible aircraft fuels.
Its one major disadvantage for this, as for most uses, is its low mass density: it needs more room than diesel to store enough to be useful. The tanks need to be bigger, and either strong enough to contain high pressure, or well-enough insulated to keep it liquid.
Current aircraft store fuel in wing tanks not roomy enough for hydrogen. The most practical hydrogen-fueled aircraft would probably have a shape more like a lifting body than a submarine with skinny wings sticking out. So for best efficiency, we might need new airframes, but just using hydrogen yields major improvement. To oversimplify, the plane doesn't need to lift so much weight of fuel to cruising altitude, or carry it halfway across the world.
Tankage has improved radically in recent years with the development of aerogels, which make practical carrying liquid hydrogen that need not held be at high pressure, so can be in tanks that conform to an aerodynamically-practical shape. (Other sophisticated storage methods increase weight, so are more practical on the ground.)
Hydrogen is tricky to store for long or in large amounts, so the best way to use it is to produce it on demand where it is needed. A major airport would be a good place to produce it, as it could be piped directly into aircraft and used immediately. All the airport would need is water and power. Power can be collected by wind and solar over a wide area, delivered by transmission lines. The amount of water needed is negligible.
Producing hydrogen would also yield plenty of oxygen, which might just be vented; but by carrying liquid oxygen, aircraft could fly higher, faster, and more efficiently, or at least get to cruising altitude more quickly. As electric power continues to get cheaper, uses for it such as liquifying oxygen along with hydrogen get more attractive.
The first use will be in long-haul craft operating from a few major airports. It is possible that current large aircraft -- 747s, 777s, A380s -- could be converted, by using some of what is now cargo space for tankage, and replacing fuel pipes and pumps and, quite possibly, engines. It would be a big job, made attractive mainly by the extreme cost of qualifying new airframe designs.
The lost cargo space would be made up easily by the much larger weight capacity, as tens of tons less weight of fuel is needed. Cargo aircraft today often fly half-empty so as not to exceed their takeoff weight limit.
How is it better than generating biogas from biomaterial, something we already do at industrial scale? What’s the advantage of biohydrogen over biomethane?
Venting methane is worse, but that would be wasteful, too.
It’s not really about that, we don’t lack water or methane. The issue is rather about the energy required to produce given amount of hydrogen. Electrolysis requires 2-3 as much energy as steam methane reforming already if you just look at energy of chemical reactions, and moreover, steam reforming requires just heat, while electrolysis requires electricity, which again is more expensive than heat: we produce most of our electricity from heat, and the conversion efficiency from heat to electricity is around 20-30%, so it makes more sense to use all the heat directly instead of going through electricity production stage.
All production issues aside, aviation makes sense to me. Planes are only filling at known stops, the weight is superior to our best batteries, and the transition from fossil fuel to hydrogen jets should be easy.
As for as long haul trucks, I can kinda see it, maybe, still a lot of storage, production, efficiency issues. Weight isn’t nearly the same concern as it is for aviation.
For cars, yea, I don’t see it.
When wouldn't it be at a loss? That's just physics. Hydrogen fuel cells aren't a source of energy in and of themselves, they're just a storage medium, like any other battery. And the act of filling them will never by 100% efficient because nothing is, so there will always be loss.
How far is that far?
HVDC only loses ten percent per 3000 km. That is it loses about ten percent transmitting almost from one end of Europe to the other.
Just connect all the national grids together properly, especially in the east-west direction so that areas with sunlight can supply areas that are dark. Also add north-south interconnects to North Africa so that hot dry areas can supply cold wet ones.
http://large.stanford.edu/courses/2010/ph240/harting1/
Appearances is that losses in transmission lines are a few percent per 1000km. Across the US is about 4000km so you'd lose a little under 20%.
Batteries don't have a rare earth metal problem, they have a normal metal problem. You need a lot of raw materials to make them, and it's plausible that this will never scale to point where everything can run on batteries.
NiMH batteries do, but who is using those?
But I mean, that has to be a limitation of current technology, right? There has to be engineering solutions that we can devise to make it as safe statistically as for example gasoline transport?
And the leaked gas, especially if in an enclosed space, is flammable or explosive over a very wide range of concentrations.
Long-term storage, transport, and use, at scale, is hugely problematic.
https://www.sciencedirect.com/topics/engineering/hydrogen-mo...
https://en.wikipedia.org/wiki/Hydrogen_embrittlement
https://www.sciencedirect.com/topics/engineering/hydrogen-ex...
So just have a small fan that constantly flows air around the container to remove all the leaked gas? They do it with heat from the batteries in EVs (which if heat up too much can explode). What is such a big deal?
I covered the topic in a series of posts based on then-new research about six years ago. That's ... not developed much further:
Primary article: https://old.reddit.com/r/dredmorbius/comments/22k71x/us_navy...
Others: https://old.reddit.com/r/dredmorbius/search?q=fischer-tropsc...
The main development since has been Foghorn, a Google (Alphabet) project attempting to develop the technology. It failed.
Not much. Hydrogen has a tendency of assuming a form that no material can hold.
People have been working on chemical storage, but the efficiency always suffer.
Clean energy sources are typically the cheapest sources of energy [0]. The intermittent production issue is solvable: At ~150 $/kWh storage, a combination of storage and renewables is the cheapest energy source 95% of the time [1].
The cost of different energy storage methods is coming down exponentially [2]. A combination of Li-Ion battery (short-term), pumped hydro (medium-term) and hydrogen (long-term, i.e. seasonal) storage is probably how to smooth out the burstiness of renewable energy production eventually [3].
When green hydrogen infrastructure is commonplace, the hydrogen can also be used to make synthetic jet fuel and feedstocks for the chemical industry.
[0] https://en.wikipedia.org/wiki/Cost_of_electricity_by_source
[1] https://www.cell.com/joule/fulltext/S2542-4351(19)30300-9
[2] https://www.nature.com/articles/nenergy2017110/figures/1?pro...
[3] https://www.sciencedirect.com/science/article/pii/S254243511...
Pakistan's big deployment is one example, it was planned to be 100MW but only produced 18MW. Mostly because they didn't factor in the dust that would cover the panels, keeping them clean was very expensive (I'm curious how this applies to other proposed desert deployments). Nor factoring in the typical malaise of public projects adding significant delays/costs, which is hardly unique to Pakistan when it comes to major infrastructure in 2020.
https://en.wikipedia.org/wiki/Quaid-e-Azam_Solar_Park
Then there's the famous Solyandra which got half a billion in US tax payer money and flopped without ever being competitive price-wise: https://en.wikipedia.org/wiki/Solyndra
Tesla's famous Australian battery factory only has enough to power 30k homes for about 1-2hrs each day. It was on-schedule, which is rare, and also makes money but scaling it up to millions of homes to make a real dent in coal would be much more challenging, especially sourcing enough lithium.
I think it's safe to take any cheery prediction from green projects and add 1.5x time/production costs and/or minus 30% of the expected output.
Note: I'm not trying to rain on the parade, I'm otherwise all for this stuff as long as it's realistic on a large scale.
The caveat being the South Australia has a power grid that is sometimes a contender for the worst managed (and most expensive) electricity grid globally. Or at least highly challenging to get it working smoothly.
So the battery is a huge success story and we'll see more like it - but the conditions where it succeeded are not necessarily where the gird wants to be.
That's a strong claim. Wholesale electricity prices in South Australia are currently around USD$45/MWh.
My understanding is that South Australia has historically always had the highest electricity prices in Australia due to dependence on gas generation within a small market controlled by two players who took advantage of their market power, but that this is starting to reverse now due to the shift to more renewables over the last decade, and South Australia may now be on track to have the cheapest electricity in Australia.
Similarly the Tesla plant is doing exactly what it said it was going to do, when it was supposed to be finished, within the budget it had, and AFAIK is making money. You're asserting that it can't scale because it... worked?!
As far as the Pakistani misdesign, yeah, I'm sure that's going to happen too. Nothing works perfectly.
Nonetheless this seems like a pretty oddly constructed list of reasons why solar is "much worse in production". It seems to my eyes like it's doing much better than expected.
Ordinary 60 or 72-cell panels are DEAD SIMPLE in their construction. It's a sandwich of a backing material, encapsulation for the cells and soldering, glass in front, with an aluminum frame and a junction box on the rear.
Solyndra "panels" are fragile, hard to transport, hard to mount, everything about them was a pain in the ass.
https://english.elpais.com/economy_and_business/2020-06-29/s...
apparently you also think the chinese government using its people's money to sell panels at a loss makes the panel cost less to produce, proving the opposite of his point?
do you actually have a point, beyond 'your point is false because of this fake argument i made up?'
With some basic equipment like rolling carts with sprayers and squeegees on extension sticks, how many individual 72-cell sized panels (1.99 x 0.99 meter size) can one person clean in one day? Multiply by probably 4 to 6 full time staff positions.
> It required one litre of water to clean, each of 400,000 installed panels. A total 15 days cleaning cycle required, 124 million litres of water enough to sustain 9000 people, while rain in Cholistan desert is rare and far between. Providing such huge amount of water in desert terrain, became a challenging and daunting task for management team. Besides, the manual cleaning methods allowed setting of dust before it was re-cleaned.
I'm not sure the phrase 'temperature differences' exhibits a profound understanding of evaporation.
If a location gets 45c (as per GP's reference) during the day, this doesn't necessarily speak to night time temperatures.
I'll note that Bahawalpur's temperature profile is available at:
https://weather-and-climate.com/average-monthly-Rainfall-Tem...
For the three hottest months of the year the average lower temperature is around 25C, which suggests quite a low evaporation rate overnight.
It would be great if you could provide some more detailed insights.
Have a swarm of these and cleaning will not be an issue.
I would imagine another challenge is the transporation costs. The nearest fresh water source appears to be Sutlej River ~18 KM straightline. The nearest seawater source appears to be the Arabian Sea, ~800 KM straightline.
The cost to a problem like this would never be labor as that can be trivially automated if it ever gets costly enough. Water is expensive at these scales.
That being said, it's probable that there could be solutions here. Automated scrubber/blower might be able to get most of the efficiency back without the cost (whether integrated into the panel or a robot on a track). Could potentially use any water more judiciously too when needed (moisten a scrub rather than blasting it with water). Don't know enough about the project but I would hope the domain experts responsible for the project would have considered something I only thought about for 30 seconds & there are reasons that they don't do that.
I imagine some glass coating should be cheap enough and efficient solution to implement.
> The nearest seawater source appears to be the Arabian Sea, ~800 KM straightline.
Sure, such plant has to be constructed near seawater source.
http://www.salaryexplorer.com/salary-survey.php?loc=164&loct...
This comes out to ~$97,000 which is how I came up with about $100,000/y.
Just to note this isn't something you do for just one month per year if that's how you came to a factor of ~10.
Some kind of brush is probably what you need for dust.
A valid example of what can go wrong when you pick the wrong technology, don't do small scale trials first, and rely on government oversight. (Refer the Background & Operation section of the wikipedia article -- toe-curlingly alarming, yet ultimately unsurprising.)
They almost definitely should have pursued concentrated solar thermal. It partly solves the 'storage problem', provides power well into the evening, doesn't need more water than they have to clean it, and improves magnificently with high temperatures (the wikipedia article cites the problem of regular 45C days, which are above the 25C optimum temperature for PV panels).
Given all this was known and understood before they broke ground, this sounds like a traditional government project problem -- susceptibility to corruption, vanity, hubris etc.
I don't know why you're trying to turn this into an "obviously govt can't do anything" point. There are plenty of very well-run governments who would have ably foreseen and solved these problems. And no doubt there's any number of private companies who would have screwed up just as badly.
Trying to tar the entire idea of government with Pakistan's performance is pretty bad faith IMO.
You're mis-quoting me. Is this intentional?
I understand paraphrasing, but there's better (and more accurate) ways of doing that.
> I don't know why you're trying to turn this into an "obviously govt can't do anything" point. There are plenty of very well-run governments who would have ..
FWIW it wasn't a 'no government can do anything' claim.
I have no doubt that there are a number of government agencies that can do things.
The fact that this particular project delivered a measurable 20% of projected outcomes is the point.
If you have some alternative interpretations of this outcome, they'd be very welcome.
> And no doubt there's any number of private companies who would have screwed up just as badly.
Are you suggesting I can't claim something is bad -- because something else would be just as bad?
> Trying to tar the entire idea of government with Pakistan's performance is pretty bad faith IMO.
This is a bold leap, and no faith is involved.
> this sounds like a traditional government project problem -- susceptibility to corruption, vanity, hubris etc.
said the person on a web forum (the web comes from CERN, a gov project) over the internet (the internet comes from DARPA, a gov project) on a computer (ever heard of the ENIAC? a gov project)
Tech bros mouthing off off-topicly about the government is the most tedious and boring thing ever.
https://techpinions.com/its-not-just-the-internet-how-govern...
Referring to GP's wikipedia reference, can you explain the two 'for unknown reasons' on a) why the original (Canadian) contract was not engaged, and b) the Turkish project was not engaged.
What precisely was ashistorical about any of my post?
> > this sounds like a traditional government project problem -- susceptibility to corruption, vanity, hubris etc.
> said the person on a web forum (the web comes from CERN, a gov project) over the internet (the internet comes from DARPA, a gov project) on a computer (ever heard of the ENIAC? a gov project)
I really am bewildered.
Are you claiming that because I'm using the Internet I am not authorised to claim that any government project in any country at any time is beyond questioning?
> Tech bros mouthing off off-topicly about the government is the most tedious and boring thing ever.
Goodness.
I'm sorry you're bored, I'm not a tech bro, claims of poorly run projects within the land of the pure isn't off-topic to the claims made.
Reading about some of the missteps of CSP, much like the above, they seem to be share similar traits of government mishandling, bureaucracy, dodgy dealings, etc.
EDIT: In any case, a naive interpretation of the Pakistan project cited -- if it truly is getting ~20% of anticipated power, cost per unit is 5x forecast, at which point a CSP would have been better value for money.
I suspect that solar thermal is in more than a lull; I suspect that it's been obsoleted by PV and we aren't going to be seeing many new installations at all.
I also suspect that mirrors are less sensitive to dust than PV cells. And that it's cheaper to just install more mirrors (flat reflective surfaces) to compensate for anticipated dust build-up, than photovoltaic panels (per unit of area or per unit of power generated).
But, really, I expect there's a fair bit of research on this subject already out there.
As I intimated, it's probably not so much an obsolescence issue, as one of pushing the storage question aside. CSPs address generation, with some ephemeral (cloud, evening, etc) storage capabilities. As per the standard observation - it's going to be a blend of power generation and storage technologies that sees us through.
The storage issue is interesting, but doesn't matter so much to most plants since they tie into a larger balanced grid, and battery storage is coming down in cost at the same exponential rate as PV. These same advantages are not accruing to solar thermal. So I do think we are seeing the death knell for solar thermal, even when energy storage is desired alongside peak production.
Storage can't be ignored - and the 'balanced grid' that we're all part of relies heavily on burning fossil fuels for both baseload coping with peaks (sun goes behind a cloud or the horizon, or the wind stops for a while). As we decom more of the fossil fuel systems, a more robust & scalable storage system, even a relatively ephemeral one, will become more compelling. (my prediction : )
>improves magnificently with high temperatures
Thermal solar is a solar heat energy source + classic steam turbine. The efficiency of a thermal->electric converter (turbine) is largely governed by the difference between the hot and cold side.
Increasing both the hot and cold side temperatures equally would not increase efficiency, AFAIK it would actually decrease efficiency, and without lots of water, they can't use evaporative cooling either.
Hence the C in CSP.
Contemporary molten salt CSPs operate at ~700C, so the difference between the concentrator and ambient air temperature would be 3% (at 25C) and 6% (at 45C).
In other words, a 3% difference. Perhaps measurable at the output, but certainly not significant.
New CSP designs are coming along that are working around 1000C, which would render that delta even more negligible.
In contrast, while PV cells vary, I believe max power temperature coefficients of around 0.4% / 1C is a standard figure.
That means at 25C your panels are losing 10% of max capacity, but at 45C that number goes up to 25%.
A massive reduction in capability.
As an aside, your calculations are improper, even though results are close enough. 0℃ is merely 273.15K and the temperature at which water tends to freeze. E.g. PV efficiency is usually quoted at 25℃ (or 300K), so at -20℃ they could generate cca 120% of "max" (rated) capacity.
https://en.wikipedia.org/wiki/Bhadla_Solar_Park
Apparently Bhadla is the world's largest solar park. I wonder if the two countries can co-operate on this (I know relations are mostly hostile currently)
> In December 2016, Solairedirect signed an agreement with Ecoppia, a PV panel cleaning solutions developer, to provide automated cleaning solutions to the project. Due to the park's location in a desert region, it is prone to dust storms
https://www.pv-tech.org/news/ecoppia-to-provide-cleaning-sol...
Hopefully the project eventually does reach the 2000MW scale it plans. It's not clear from the Wiki how far along it is or whether it's currently operational. It mentions opening targets for Dec 2018.
Softbank is involved for 500MW which is one red flag :p
You/[1] is saying that with storage costs of USD 150,000 per MWh, renewables can be competitive? It doesn't compute, unless I misunderstand something.
With the hydrogen you have so few refueling stations, they are very expensive, that range anxiety is a thing. To not improve things, reliability is very poor. My work had a hydrogen refueling station on its parking. It was often broken and actually a bit scary to walk past it. They eventually removed it, which was a good call. Another hydrogen station sharing the same design exploded a few months later. The hydrogen car sales dropped from not much to virtually zero since in the country.
So to resume, hydrogen cars are expensive, refueling stations are expensive, the energy is expensive.
Electric cars with large batteries are a much better solution to hydrogen cars IMHO. You can charge everywhere, the eletric grid is very will developped, the energy is cheap. The cars are also much more powerful thanks to the large batteries pack, it's useless but it feels nice.
It's for long range trucks that we will see hydrogen first. Green hydrogen will act as energy storage, big renewables grids can dump excess into green hydrogen and thus avoid curtailment. Then, you replace heavy duty trucks, which need to be able to not have heavy batteries, with fuel cell trucks, and you build out 1000 large hydrogen stations across the transit network.
The fact that EV players actually delivered and built charging networks should offer plenty of proof as to which technology is more viable.
It took decades to build out the network of gas stations across countries. The reason it took much less to build out charging networks is because the power grid already existed, we already had 95% of the infrastructure for delivering the "fuel" for EVs.
But hydrogen companies are still talking as if it's super simple to build out a hydrogen infrastructure. Why would that not take decades as well? And that's assuming there was some kind of massive consumer demand for hydrogen vehicles, which there just isn't.
Even then, fuel cells are not super inefficient. At the low end of efficiency, PEM fuel cells are already more efficient than the vast majority of current generation ICE vehicles. And with SOFCs with novel heat recuperation technologies, 85-90% efficiencies are already achievable.
As planes and boats expend fuel, they get lighter, so less fuel is needed to move the second half of the journey, and less for the last quarter, etc. That “bonus” doesn’t work out with batteries, you need to move all the weight for all the journey. The energy density of batteries, to my understanding, just doesn’t add up correctly for boats or most airplanes.
What I would like to know is, wouldn’t a hydrogen-powered boat or plane not only have a similar calculation on how much fuel is needed, but also (in the case of boats) be even cheaper to move because its fuel payload is lighter than water? Water 997kg/m3 vs liquid hydro 71kg/m3, also gasoline 783kg/m3, sounds like a nice bonus for jumbo jets too. (I am NOT a physicist or mechanical engineer)
Gasoline-powered sea vessels are terrible polluters, incidentally, accounting for 18% of all air pollution. Between the air pollution benefits and possibility of the vessels being so much more fuel efficient, it seems like hydrogen would be a benefit even if the production isn’t completely clean.
For metal-air batteries, one of the more promising areas of research, the problem is actually worse: the cells gain mass as oxygen is reacted with the metal anode, discharging the battery.
https://en.wikipedia.org/wiki/Metal–air_electrochemical_cell
For marine propulsion, heavy fuels are typically preferred (bunker fuel typically, thogh deisel and petrol engines do exist). Much of the pollution is in the form of particulates and sulfer emissions. You can actually see major shipping routes on atmospheric sensing maps by SO2 emissions:
https://earth.nullschool.net/#current/chem/surface/level/ove...
As long-term risks these are ... somewhat minor as these contaminants settle out quickly: in days to months rather than centuries to millennia for CO2 and methane. Not great for respiratory health, but not the long-term planetary risk fossil fuel combustion overall is.
That's interesting, thank you for the info. Having a different characteristic from the usual one might lead to interesting applications. For instance, airplanes use a lot of fuel for takeoff, as they pay double the price for the weight of their fuel: they need to carry it up, when they have the most. This could actually be a game-changer, I think.
That could also be exploited: raise the battery when it is charged, have it gain weight, generate electricity while lowering it. Perpetual motion doesn't exist, of course. But gaining a bit of extra mileage is theoretically possible here :)
The bulk of energy expenditure is on takeoff and climb segments of flight. Cruise is relatively low energy, and during approach and landing, aircraft are frequently effectively gliding. Pilots and aviation engineers speak of the amount of energy in the aircraft, exclusive of fuel, represented by its mass, altitude, and velocity.
Ideas I've seen suggested include catapult or towed launch, ejectable or jettisonable batteries, and/or hybrid fuel/electric designs, exploiting these factors.
The general problems are:
- These all increase complexity and failure risks.
- They are novel (and hence risky) concepts.
- Virtually all have scaling issues, being possibly feasible for smaller (drone, single-passenger, or few-passenger craft), but not heavy or superheavy jumbo jets. (Square-cube relations mean, generally, small aircraft are easier than large ones).
- The typical power requirements are violated in emergencies. Fuel-driven aircraft can apply TOGO (take-off/go-around) power on demand, whilst a hybrid or compound design likely could not. And final flight-phase aircraft typically have half their takeoff weight, having burnt the difference in fuel, further expanding performance options.
As for "lowering the battery", you'd do better to fly the entire aircraft at a gradually descending flight path, trading lower-drag high altitude for higher-drag lift as the battery gains mass. Current long-haul aircraft (sometimes) practice this in reverse, reching higher flight levels as fuel is consumed, lift requirements reduced, and lower-drag high-elevation flight being possible.
For comparison, an ES44AC [https://en.wikipedia.org/wiki/GE_Evolution_Series] carries 18900l of diesel (weighing 15.7 tons), which at 38.6 MJ/l rounds to 730GJ of energy. Hydrogen seems to have a specific energy of 120-142 MJ/kg, using the conservative 120 that's about 6.1 tons of hydrogen, but now for the volume... https://www.energy.gov/eere/fuelcells/hydrogen-storage lists "0.03kg/l" as a "system target"... so 6.1 tons is 203,333l. That's 2 conventional tank cars (but those don't have any cooling or pressurization systems.)
(Of course this assumes the efficiency of diesel->electrical and hydrogen->electrical to be similar, which is not the case.)
P.S.: https://en.wikipedia.org/wiki/Hydrail & https://www.bbc.com/future/article/20200227-how-hydrogen-pow...
Heavy trucks are also a much bigger issue than international shipping, which is only ~2% of global GHG. 6.7% of US GHG emissions come from medium and heavy duty trucks, or 23% of emissions due to transportation.
Maybe the local administration could offer some incentives to companies that have this.
I was trying to evidentiate that charging stations built by tesla supplement home charging or any normal outlet. It's a bit different than building a network of superchargers because the demand would be a lot higher because a hydrogen powered car will be fully dependent of those specially built charging stations.
The main idea is that a BEV owner doesn't need a supercharger station to use his car. Sure, it'll be nice, but not mandatory; let's not forget that not everybody lives in US or W. Europe where the network is more developed.
For long distance trips, yes. But unlike with hydrogen vehicles, charging at home is an incredibly simple proposition for BEVs.
Electrification completely upends that. A country that is self sufficient in energy can tell other countries to take a hike.
Electric cars are still very dangerous when they catch fire though. And the fires are very difficult to control. Especially in multistorey (or underground) car parks. And even more so if there are multiple EVs parked next to eachother.
“As an example, a 100kWh battery will give a potential range of 250 miles and, in order to produce that battery, it will take around 20 tonnes of CO2,” he said. “A typical battery lasts for 150,000 miles, so that equates to around 83g/km of CO2. Then, when you take into account charging over that same distance, the same battery car will deliver 124g/km of CO2 over its lifetime.”
By comparison, Auto Express says that a recent study found that a Toyota Mirai hydrogen fuel cell car produces around 120g/km of CO2 over its lifetime when the manufacturing process is taken into account. But if hydrogen were to be produced by renewable energy, that figure could be reduced significantly.”
Source: https://www.theweek.co.uk/electric-cars/101196/hydrogen-fuel...
https://www.autoblog.com/2020/06/11/catl-million-mile-batter...
2.) Energy required to produce the batteries will eventually shift to zero emission sources.
3.) Materials can be recycled from the battery even after its million+ mile use.
It’s hard to overcome the energy required to produce hydrogen plus the bad efficiency of fuel cells compared to batteries/electric motors.
If this co2 is due to electricity/transportation cost then the problem will solve itself with more electricity from green sources.
He has literally spent the last five years debunking this nonsense. Here's a thread from just 5 hours ago: https://twitter.com/AukeHoekstra/status/1279359481177083904
TL;DR: These comparisons always use too much energy for battery production, too high efficiency for gasoline cars, and fail to take into account that the grid is rapidly decarbonising, even in backwater countries like USA. Your source claims 20 tonnes for battery production, but reality is around 6 tonnes and falling due to grid decarbonising.
There is a persistent narrative in Germany that diesel cars are better for the environment, and your comment is playing into that. This narrative is wrong and damaging.
Why are you doing this?
What am I ‘doing’ exactly, pointing out a fact that there is no ‘free lunch’ when reducing emissions?
“The Belgian newspaper De Standaard published this claim on their website on the 18th of April. We rate this claim as mostly false.”
Again, even if the cost of b battery production in Germany two years ago was 15 tones, it doesn’t matter. Why? Because Germany made almost no car batteries two years ago, and the grid is rapidly decarbonising - in Germany and most of the world.
Now, if you are arguing that it would be better if people lived closer to where they work, and stopped driving cars altogether - I’d agree with that. But cars will continue to be with us for a long time, and the Sonne we can transition the fleet to electric the better.
Hydrogen is a difficult thing to manage in quantity. Its density is fantastically low, so storing it in gas form requires absurd pressures -- an inherent risk to any vehicle. Storing it in liquid form goes a long way towards solving the density/pressure problem, but now the system must have a full cryogenic process to keep the hydrogen liquified. (Worse yet: over time hydrogen embrittles (https://en.wikipedia.org/wiki/Hydrogen_embrittlement) metals, making storage even more complicated)
This isn't much different than the problems faced by rockets, and it's why liquid hydrogen is not considered a 'storable propellant' for long-duration flight.
In a zero-net-carbon economy, residual demand for high power density may still have to be filled by some kind of bio-derived or synthetic hydrocarbon.
Edit: this video had a good overview of the various production methods, including on-site at the fuel station https://www.youtube.com/watch?v=f7MzFfuNOtY
1. The only hydrogen produced from electricity is ecological. Carbon capture doesn’t work today.
2. The hydrogen from electricity is expensive, though as wind and solar get exponential cheaper, we will end up with spikes excess cheap electricity (negative prices today or disconnecting plants). It makes sense to produce hydrogen during those spikes.
3. Cars on hydrogen don’t make sense at all. The massive cost of infrastructure plus batteries are superior and getting better on that front.
4. Hydrogen from electricity can replace the first reformation from natural gas.
5. Next promising use cases are industrial heating, such as steel production (instead of coal).
6. Least profitable, but still plausible, uses hydrogen as long-term energy storage and mixing it with natural gas.
7. I wonder whether generating hydrogen from seawater and getting back freshwater would improve the economics of this form of energy storage.
I'm not sure that it necessarily does. If you're only producing during those peak periods of electrical output then your you're going to have a lot of hydrogen producing equipment sitting idle at other times.
(1 kg of hydrogen would make a few gallons of water)
Well that's just not at all true. Hydrogen by electrolysis costs <$20/kg. A much more interesting fact about a kg of hydrogen is also that it has very close to the same energy content as a gallon of diesel, and significantly more when used in a fuel cell vs an ICE.
I was responding to point 7, not comparing hydrogen to diesel.
But it's still just a battery, and needs to be charged from the electric power grid (by using the electricity to separate hydrogen from water), just like any other battery would.
https://www.carboncommentary.com/blog/2020/6/17/renewables-p...
Lots of comments on this thread that reveal folks are up to date with the state of hydrogen infrastructure c. 2017. It's changing really fast as billions of dollars are poured into R&D and pilot projects. For example, storage and transport:
https://uk.reuters.com/article/uk-japan-hydrogen-chiyoda-cor...
Siemens has pledged to make turbines that run on 100% hydrogen by 2030: https://new.siemens.com/global/en/company/stories/energy/hyd...
Hydrogen trains: https://www.snam.it/en/Media/Press-releases/Agreement_Alstom...
Hydrogen in steelmaking: https://www.spglobal.com/platts/en/market-insights/latest-ne...
I could post 15 more. Our collective priors were well-grounded just a couple years ago, but it is time for a big update.
So even with carbon free heat production cement industry would still generate a lot of co2 :/
Think people building sky scrapers in areas with exposure to earthquakes and tropical storms safe. I'm talking about Tokyo. https://www.theguardian.com/cities/2018/feb/16/plyscraper-ci...
Hydrogen is not really needed to fix this.
For electricity, as the renewable energy generation capacity will increase, Storage of excess will be essentially required. when in near future we develop viable tech to generate hydrogen from electricity with low or no carbon impact at reasonable efficiency,we can save them in underground reserves(Safest way in my view) and use existing piping infrastructure of natural gas for its transportation. we need to do research and wait for appropriate tech to be available.
On that graph, compared to petrol, liquid hydrogen appears to be about 4x larger by volume but interestingly only 2/5ths of the weight.
The electric motors are lighter sure, but then what about the mass and volume of the compressed storage tank and the fuel cell itself? difficult to know if it starts to gain on IC engine again. lots of questions that make that graph feel pretty meaningless.
Small-scale alcohol fuel production integrated into regenerative agriculture farms is different from mass ethanol production.
You can ferment anything that has starch or sugar, the leftovers from the distillation can be composted or fed to livestock. Most existing internal combustion engines can be modified to use alcohol fuel. And it's carbon-neutral.
If you've got a ready source of hydrogen, say from molten salt oxidation of plastics, which produces "syngas" (a mixture of CO and H2), I think you could run that through water to make CO2 and more H2, feed the CO2 to a greenhouse and collect all the H2 for the reaction you described. Does that make sense?
There are some marginal gains possible, but on the order of single-digit percentages of present fossil fuel consumption. Maybe low double-digits.
The US had a largely biofuel based transport system in 1900. Horses consumed 20% of all US grain production, the population was under 100m, and transport generally was a small fraction of today's values (or at least last year's) per capita: closer to 300 mi/yr, much of that walking, than 15,000.
The key is that you're producing the alcohol as part of an integrated system of production that mimics Nature. You have a farm that requires no inputs (of fertilizer, and in some cases no irrigation) that produces multiple crops per year. ("Syntropic" agriculture, "Permaculture", food forests) You can grow sugar beets, yams, sugar cane, or starchy plants such as potatoes, certain kinds of reeds, tubers, etc. directly for fermentation, or use scrap fruit from the orchards, etc. Literally anything that has starch or sugar can be used as a feedstock. Scrap dough from a (doughnut) bakery.
The leftovers from the fermentation and distillation aren't wasted: you feed them to livestock. Because it's a yeast culture there's more protein in it now than it had before.
So your farm produces fruits and veggies, meat, and alcohol fuel.
(I'm getting all this from http://alcoholcanbeagas.com/sitemap )
Of its nearly half a billion acres of prime cropland, the U.S. uses only 72.1 million acres for corn in an average year. The land used for corn takes up only 16.6% of our prime cropland, and only 7.45% of our total agricultural land.
Even if, for alcohol production, we used only what the USDA considers prime flat cropland, we would still have to produce only 368.5 gallons of alcohol per acre to meet 100% of the demand for transportation fuel at today’s levels. Corn could easily produce this level—and a wide variety of standard crops yield up to triple this.
A decade ago biofuels were my first thought. The maths simply don't add up. Our options are far less energy per person, far fewer people, other sources of energy, or, most likely, some combination of these.
The highest claimed yields are for algae, at a rather improbable 1,000 gal/(acre * year):
[Y]ou might consider floating the algae offshore, along the Pacific and Atlantic costs. It's roughly 1,300 miles from San Diego, CA to Port Angeles, WA, and 1,800 miles from Homestead, FL to Lubec, ME. Dividing our 443,000 square miles by those two added together, we find we'd have to extend our grow region some distance off-shore. That is, 143 miles off-shore. The full length of both coasts.
Or perhaps you'd prefer to re-purpose the Gulf of Mexico. Its total area is about 600,000 mi2, we'd need about 3/4 of it dedicated to algae growth.
https://old.reddit.com/r/dredmorbius/comments/2cvap7/the_int...
Tom "Do the Math" Murphy:
https://dothemath.ucsd.edu/2011/11/the-biofuel-grind/
https://dothemath.ucsd.edu/2011/08/garbage-in-garbage-out/
The late David MacCay's Alternative Energy Without the Hot Air gives a comprehensive breakdown for the UK of alternative energy options. Again, the picture is bleak.
The takeaways are we use a lot of energy and there are a lot of us.
https://www.eia.gov/energyexplained/oil-and-petroleum-produc...
That's 595,000,000 * 365 = 217,175,000,000 gallons per year of oil.
Using 100% of cropland producing at 369 gallons of ethanol/acre gives
434,164,946 * 369 = 160,206,865,074 gallons per year of ethanol.
That's only 74% as many gallons as oil consumption.
It's actually much worse than that, because the energy content of a gallon of ethanol is only about 65% the energy content of a gallon of oil:
https://en.wikipedia.org/wiki/Energy_density#Tables_of_energ...
This much ethanol would only provide 48% of the energy currently consumed by oil based transportation.
It's actually much worse than that because most crop land is already used to grow crops eaten by animals and people. If we feed all the crops to transportation machinery, others will go hungry.
The problem is scale. We eat far less food than we burn fuel. So replacing our fuel with a by product of food production is not going to scale.
Bio fuels at scale only make sense with heavy subsidies currently E.g. the corn industry in the US is a good example of something that would not exist without subsidies.
Edit: I found an article about this. It appears to have been developed by the military and has been licensed out for more development: https://techxplore.com/news/2019-07-h2-power-hydrogen-fuel-s...
What would the energy source be? It does not matter what chemical or electrochemical reactions are possible in general, what matters is where does the energy come from. Water does not contain any energy. (Not any chemical energy that can easily be extracted. Of course it contains energy in the sense that E=MC^2, but in that sense we have about the same chance to run a car on sand, or rocks or oreos.)
On the other hand, if you do have an energy source, then why would you need water at all?? You would just use the energy to drive the car (like EVs do), you wouldn't waste half of it to hydrolysis of water into hydrogen first to use that hydrogen...
A theory about a "car running on water" (which, at least in my experience is often followed by conversations about how Nicola Tesla could transfer energy through the air, or about how government has all the technology for infinite energy, but they block it from being used because they are evil) - is a pipe dream which is heavily based on ignorance about physics and gross underestimation of the difficulty of real engineering problems.
Saying this ignores basic physics is like saying gasoline engines ignore basic physics. No one is saying that it's free energy. The question is, what is the energy to produce/recycle the alloy? How many miles can you get out of a reasonable supply of the alloy before replacing it? If those numbers are good enough, maybe they'll perform better than battery vehicles. And so I'm asking what's the state of that research.
Its a shame this article didn't examine the production side of hydrogen.
I saw this article earlier today along those lines: https://www.smh.com.au/environment/climate-change/alchemy-of...
Supposedly this stores hydrogen metal hydrides cheaper than lithium batteries, whatever that means, but I'm not qualified to judge.
[1] https://www.jacobs.com/sites/default/files/2020-06/jacobs-ya...
The lower the energy used by a generator, the higher its efficiency would be; a 100%-efficient electrolyser would consume 39.4 kilowatt-hours per kilogram (142 MJ/kg) of hydrogen,[24] 12,749 joules per litre (12.75 MJ/m3). Practical electrolysis (using a rotating electrolyser at 15 bar pressure) may consume 50 kW⋅h/kg (180 MJ/kg), and a further 15 kW⋅h (54 MJ) if the hydrogen is compressed for use in hydrogen cars.
It's not great, but it doesn't seem unworkable. I can't read the article, but isn't the idea to use hydrogen tanks as a battery to smooth out the variability of renewables like solar?
[1] While Tesla’s V3 Superchargers are amazing in that charging stops can now be as short as 10-15 minutes to for 100+ miles of range - Superchargers should not be used for day-to-day charging because it wears out the battery too much (hence the hype over the new generation of Lithium cells, that “million-mile battery”, but for the rest of us using current-gen Lithium batteries (myself included, I drive a Tesla too) I don’t want to have to drop $20k+ for an out-of-warranty battery replacement).
Total US sales in 2019: 1502.
It's just not selling.
...and that's the problem. Gasoline, diesel, and electricity are all far easier to find than hydrogen.
(Electrolysis is also extremely inefficient, for those who might be wondering.)
By 2050, energy cost is going to be measured differently. IMHO it stops being a variable cost once it dips substantially below 1c per kwh. Your basically spending more on coffee to keep yourself going on an average journey, Arguably, if you have access to square meters, it's a cost that is amortized over the one time cost of installing wind turbines, solar panels, batteries and other infrastructure. Kind of expensive today but doable; that will be very much different 3 decades from now.
Any business operating fleets of vehicles will want to minimize this cost. That means investing in cheap sources of energy and a mass switch to battery electric vehicles that is already kicking off right now. This takes time obviously and doesn't happen overnight. But it's also not going to take decades. It's one of those things where the payoff is non linear meaning it goes from "oh wouldn't that be nice" to "I must do this now to survive as a business" in just a few years. In other words, this will have largely been completed by 2050.
This is good news for hydrogen as well because it means that there will be plenty of excess energy from peak solar/wind that's basically there to be used. Producing hydrogen and other synthetic fuels (and water) is an obvious way to put that to use and can be used as a solution to fix e.g. shipping, heavy industrial use, and other sectors currently depending on oil or coal. That's after we've topped up our TWH of deployed grid and ev batteries of course.
And maybe we'll figure out fusion as well by that time.
While only tangentially related, a lot of people think about the Hindenburg accident when talking about either hydrogen or dirigibles. But those contain less fuel than an airplane, at least in terms of energy. And 35 people died, around a third. To contrast with airliner accidents. But it sure left a mark on collective psyche. And I agree that hydrogen is incredibly volatile and explosive, which isn't a good fit for every application.
Tldr: Impossible for civilization to make an instantaneous non-gradual switch to hydrogen fuel cells.
People like Hydrogen because they're hyped about how it is:
- Clean
- Plentiful
- Emission-less
Hydrogen is difficult to handle.
- Unwieldy as a gas
- Boils at 20 degrees F/ - 6 degrees C / ~420 Kelvins
- Tough to maintain at a high pressure.
To go 300+ miles or ~480km or more on hdyrogen is ugh tough.
H - 120 MJ/kg
Gasoline - 44 MJ/kg
Volume wise, ugh.
H- 8 MJ/L
Gasoline - 32 MJ/L
You need ~5-10 kilograms of H2 to deal with light duty vehicles.
Compressing the stuff is annoying.
Training and retraining all the gas station attendants to deal with cryogenic materials is no small undertaking.
There's 100K gasoline/diesel stations in the USA.
Very special handling for hydrogen.
Hydrogen penetrates metals.
Makes metals the enemy and things can wear down unexpectedly. Scary stuff. Preventative maintenance is complicated.
Gasoline has ~4x-8x the kwh per a gallon to compressed hydrogen fuel. (my calculation might be a bit off, but not that far off.)
Pumping hydrogen into a vehicle is done slowly from my recollection.
Hydrogen's explosion risk is extreme, the spark from the leak could cause it. eekkkkk.
Hydrogen's flames are invisible. It's a pale blue flame that's difficult to see during the day.
People might come back and say there's progress with magnesium adn/or carbon nanotubes or other things, but they're all meh and don't scale.
Hydrogen has a shitty power to mass ratio. It escapes independently/leaks out easily without you knowing. It's dangerously explosive!
It emits lots of CO2 to make the stuff. CH4+O2 = CO2+2H2 Makes the whole thing seem like a pointless exercise.
The efficiency of manufacturing hydrogen for fuel usage is probably like 10% to 30%. Can't imagine it being more than that.
I'm not a Chem E though.
To make a cryogenic pipeline system in the USA for H2 would cost $1T+
Every year I get asked about Hydrogen, it's all BS.
Any scientist that says it's highly viable has me wondering how much money they wasted on their degree.
In practice, hydrogen @10 kpsi/70 MPa is currently a bit over 1 MJ/L when including the tanks. Gasoline is misleading as well, because a fuel cell is easily twice as efficient as a gas engine and up to 3x.
Li-ion batteries are anywhere from .5 to 2.5 MJ/L, for reference. Thing is, volumetric efficiency is all but irrelevant for most applications. Even airplanes have huge amounts of empty space that could accommodate tanks; container ships would be less efficient but that's about it.
> You need ~5-10 kilograms of H2 to deal with light duty vehicles.
5 kg will take a Toyota Mirai over 300 miles.
> Training and retraining all the gas station attendants to deal with cryogenic materials is no small undertaking.
This is not a thing. Attendants don't need to do anything with cryogenic anything.
> Hydrogen penetrates metals. Makes metals the enemy and things can wear down unexpectedly. Scary stuff. Preventative maintenance is complicated.
This is an issue when you're trying to build electron microscopes, not when you're fueling cars. The diffusion rate of hydrogen is negligible for everyday purposes like safety. Certain parts need to be designed to avoid embrittlement, but it's a minor problem- embrittlement is only really an issue at VERY high temperatures. If the steel isn't glowing, it's a minor issue, and for most other metals it's even less of an issue.
> Pumping hydrogen into a vehicle is done slowly from my recollection.
It's as fast as a highway pump, and often slightly faster. It's pretty hard to pump slowly when 10 kpsi is involved, after all.
> Hydrogen's flames are invisible. It's a pale blue flame that's difficult to see during the day.
Typically it just explodes, unfortunately. Hydrogen is always at such high pressure that it spreads out rapidly and sustained flames are very unlikely, and then there's the fact that the energy density causes things to break.
> The efficiency of manufacturing hydrogen for fuel usage is probably like 10% to 30%. Can't imagine it being more than that.
Commercial processes are ~60% and non-commercial are above 80%.
Alternatively you could equip the trucks with batteries and connect them to the electrical grid via overhead lines similar to trains for recharging. Combined with autonomous driving those trucks could go non-stop and leave the highway with full batteries.
(I just assume Toyota isn’t going big on the Mirai for the same reason Ford and GM still only pay lip-service to BEVs: they don’t want to upset their dealer network too much)