Slashdot Mirror
Hydrogen Stored in Safe High Density Pellets
sunbeam60 writes "A group of scientists are going to present their breakthrough in hydrogen storage this Wednesday. In contrast to previous storage mechanisms, this method binds hydrogen to a pellet which is completely safe to handle at room temperature. While bound in this medium no hydrogen loss occurs, enabling hydrogen to be stored cheaply for indefinite periods. When needed, the extraction of hydrogen is relatively simple. The pellets exceed all criteria set by the US Department of Energy for 2015, enabling a car to drive more than 500 km on a 50 L tank (13 MJ/l)"
If you crash into another car, do you get to steal the car's pellet and absorb its power?
There seems to be information in the summary that is not substantiated in the referenced article:
While bound in this medium no hydrogen loss occurs, enabling hydrogen to be stored cheaply for indefinite periods.
The article referenced mentions nothing regarding hydrogen loss (or lack therof).
When needed, the extraction of hydrogen is relatively simple.
Is it? Again, nothing in the article about the extraction process.
So where did the submitter get this extra data? If this data is correct, we'd appreciate a link.
If, however, this detail in the summary is unsubstantiated, we'd appreciate less speculation in the future.
____
~ |rip/\/\aster /\/\onkey
The new pellets could also bring about a renaissance for giant hydrogen-filled airships, or as they will now be known, beanbags.
... they decided to coat these pellets with a mixture of iron oxide and aluminum powder.
I got 23 miles to the US gallon.
500 km is about 310 miles.
50 liters is about 13 US gallons.
This is comparable to many US sedans. The question is whether the cost of hydrogen processing will be more or less expensive than the cost of refining oil.
If he was really up to that task, he would have posted his reply twice.
Slashdot doesn't need editors that don't take that initiative!
I saw an article earlier that talked about hydrogen pellets but they were using them to recharge laptop batteries. It could be similar technology but this article talks about how it works. http://news.uns.purdue.edu/UNS/html4ever/2005/0508 28.Varma.fuelcells.html
The question I have is how do we get the hydrogen back out?
The linked article calls the stuff "AMMINEX" which sounds like yet another ammonia hydrogen storage scheme. I won't comment on their implementation but others have failed here.
The next problem facing hydrogen as an energy carrier (NOTE - never use the term "energy source" when referring to hydrogen because it only carries energy that has to come from somewhere else) is the fuel cell, which requires costly noble metal catalysts (i.e. - platinum). The whole electrolysis process is highly alkaline so conventional metals are quickly fouled.
More
Danish website ing.dk (run by the danish union of engineers) says in their article, that the hydrogen is store as ammonia in pellets made of seasalt. The hydrogen is released by way of a catalyst (they dont explain how or which catalyst is needed). But i suppose this means the pellets are highly reuseable. If you can read danish, theres a lot more here: http://ing.dk/article/20050907/MILJO/109090025
The pill consists of ammonia absorbed in ordinary seasalt.
The ammonia is made catalytical by combining atmospheric Hydrogen and Nitrogen.
It can be stored as long as necessary.
Only when the ammonia is passed through a catalyst the Hydrogen is released.
When the pellet is emptied, it just needs a new shot of Ammonia to be ready again.
(I believe that heating is necessary in the catalyst)
Max M - IT's Mad Science
This press release of the Danish Univeristy may shed some light on the material:d =%7BE6FF7D39-1EDD-41A4-BC9A-20455C2CF1A7%7D
http://www.dtu.dk/English/About_DTU/News.aspx?gui
Nyh
That 10 liters per 100 km (23.5 MPG) is gasoline talk. US DOE wants to store hydrogen into a 50 liter (13.2 gal) tank and be able to drive 500 km (310.7 mi). What makes that challenging is the low density of hydrogen, only about 89 g/m3 (0.089 oz/ft3). High pressure tanks are either very heavy or very expensive, and chemical storage solutions always include reforming equipment or other processing steps to get hydrogen out.
Therefore, we should look at the energy content of the hydrogen stored into that 50 liter tank. With what Amminex claims, they can reach an energy content of 486 MJ (461 kBTU), versus 2150 MJ (2.0 MBTU) of 50 liters of gasoline. 486 MJ equals to 11.3 liters (3.0 gal) of gasoline equivalent. That makes 2.3 liters per 100 km (104.1 MPG!)
How is that possible? Fuel cells, electrical engines and braking energy harvesting. Fuel cells are electrochemical energy conversion devices that are free from the Carnot engine efficiency limitations, and furthermore, their efficiency increases on partial load. Operating a heat engine on partial load is detrimental to efficiency.
The aim of science is not to open the door to infinite wisdom, but to set a limit to infinite error.
-Bertolt Brecht
I think that the catalyst problem is more solvable than the more fundamental problem of hydrogen source. It bothers me to no end when people tout hydrogen fuel as pollution free. It's not. You only move the source of pollution away from the highly visible tail pipe.
There are two sources of hydrogen, electrolyzing water, and stripping it from hydrocarbons. Both of these sources suffer severe drawbacks.
Electrolyzing water is short sighted at best. The second law of thermodynamics (which we obey in this house!) dictates that it will always take more energy to get the free hydrogen that you can ever get back in a fuel cell. This means that it will take a LOT of power to supply a hydrogen economy which means new power plants, which means burning more natural gas and coal. The single best leveragabile solution to a hydrogen economy is new nuclear power plants... Wait isn't nuclear bad? At least that's what the majority of the public thinks so it won't happen. The tree huggers of this world like to think that we can supply hydrogen with windmills, solar, and tidal power. Now while these alternate energy sources certainly merit investment we are a looong way from being able to produce anywhere near the energy needed to supply millions of autos with hydrogen.
The other option is, well ironic. We need fuel cells to free ourselves from foreign oil. So we'll get the hydrogen from hydrocarbons. We'll call them hydrocarbons, so that Susie Homemaker won't immediately pick up on the problem that hydrocarbons are foreign oil. Sure it can be more efficient from wellhead to power, which is undeniable a good thing. The problem is that if it works it will reinvigorate the commuter culture here in America, which will exacerbate the problem.
In conclusion the hydrogen economy is uneconomical, and will never happen. But then again the same is true of ethanol-blended fuel, so we can always prop it up on free government subsidies.
enabling a car to drive more than 500 km on a 50 L tank
That would be 311 miles in 13.2 gallons.
Hah! I spit on your so-called metric system.
Dihydrogen monoxide is one of the most dangerous substances known to science!
-----
Sorry, I'm only a 1336 h4x0r.
Yes, water is a greenhouse gas. What the OP doesn't mention, however, is that the water lines are already saturated in Earth's atmosphere--adding more water to the atmosphere won't increase the greenhouse effect one bit.
You answered your own question there. The hydrogen economy is *not* uneconomical, but the fossil fuel based method of making it is. Fossil fuels (coal, petroleum distillates, natural gas, etc.) will run out. Maybe not in our lifetimes, but probably in our immediate offspring's lives. They will become scarce in our lifetime, and very expensive. When this happens, economics takes hold and the cheapest solution appropriate for a global scale will be used.
Nuclear power is a short-term solution. It's pretty clean, nuclear reactors are safe (at least far safer than gasoline refineries; if you live on the southeast side of Houston, you know what I mean.) We'll eventually figure out how to make fusion work, I think it's only a matter of time. But the nuclear/hydrogen combo is pretty clean compared to the double whammy of coal/gasoline. And soon to be much cheaper in comparison.
[...] dictates that it will always take more energy to get the free hydrogen that you can ever get back in a fuel cell
You are correct. The reason it is economically viable is that the human race has at least two virtually unlimited supplies of the very energy we need to break the hydrogen loose and today they go unused in any real capacity. That energy source is either solar or nuclear. Other sources could be viable as well eventually, such as geothermal.
The issue is that we need an energy storage and transportation method that works within our current tech development. Using hydrogen for portable power and electricity for stationary power is feasible as long as we can use an energy source that is plentiful and currently underutilized. Hence, solar or nuclear are the only real possible solutions right now. Solar would be best, considering the Earth receives 5000 times as much solar energy as we currently use in oil equivalents. Nuclear fusion might be a good alternative but I withhold making any concrete statements until we manage to get our first commercial reactor going. Modern nuclear fission reactors are perfectly feasible and safe as long as we manage to keep them out of the hands of terrorists (Note: The US has ZERO modern designs in operation -- we still use highly dangerous designs from the 50's and 60's).
So, in the sense that it takes more energy to break apart hydrogen than you get back from recombining the hydrogen, you are right. But it is practical to use hydrogen as an energy carrier because there is so much under utilized energy sources at our disposal, sources that do not make very good portable energy supplies by themselves.
The NSA: The only part of the US government that actually listens.
Solar is too inefficient with current technologies.
Although, depending on how you think of it, we've been using stored solar energy all alone. AFAIK, the best solar cells available are plant cells. Using solar energy and storing it in hydrocarbons. When the plants are fossilized, we get fossil fuels.
The question in my mind is, can we simply bypass the 'fossilization" requirement. Wired had an article about one possibility a while back.
I got 1,100 km on my 55L tank just this weekend. What's the trick?
Diesel. Jetta. And my fuel was 30% cheaper than regular unleaded. And I filled up with 20% Bio-Diesel blend before my trip.
The one major drawback to nuclear energy is the long term disposal and maintanance of the radioactive waste.
Right now, there are coal plants around the globe that are merrily spewing radioisotopes into the atmosphere; some coal has levels of uranium of 10ppm, and even higher levels of thorium, and just the amount of uranium the US has spat into the atmosphere since the 1930s could have, if fissioned instead, provided the entire present-day electrical demand of the entire United Kingdom for centuries. Seriously, I'm not joking. Since 1937, in the course of burning coal the US has dumped 145,000 tons of uranium into the atmosphere. That's 10,440 tons of U-235, which fissions to produce about 17.6 kilotons/kilogram. Fission all that, you get 193 petawatt-hours, which is the current electrical demand of the entire UK for 500 years.
That's real radioactivity, that causes real illness and kills real people. So why isn't burning coal prohibitively expensive? Why doesn't the 'disposal and maintanance of the radioactive waste' drive the cost up?
The reason is because the regulations for dealing with radioactive waste are a joke. They've got little to do with real risks, real costs, and a lot more to do with public fear and hysteria over anything that has the word 'nuclear' in it, which is why if you twist your knee playing football you go to get an MRI scan instead of an NMR scan. If a human being were considered under the regulations dicating the disposal of radioactive waste, then simply the naturally-occurring radioisotopes in the body would make cremation or burial in wooden coffins illegal. But nobody's bothered by that, either because they don't know that all organic matter is radioactive, or because they think that somehow K-40 in organic tissue is different from K-40 that's sitting in a used fuel rod.
Blaming public ignorance, fear, uncertainty, and doubt for the high cost of nuclear power does the best technology we have available to us if we want to maintain our standard of living *and* clean up the planet a great disservice. Right now, every kilowatt-hour we get from burning coal dumps 2.3 pounds of CO2 into the atmosphere, so for a country like the UK which gets 74% of its power from burning coal, that's 614 billion pounds of CO2, every year.
There is no way in hell the real costs of handling nuclear waste even come close to the costs of all that pollution. No. Fucking. Way. In contrast, a typical, 1000-MW nuclear plant produces something like 20 tons of high-level waste per year; that's under 50 *pounds* of waste per megawatt of plant capacity, and since it's so dense, volumetrically that's practically negligible.
Much of the high cost of nuclear waste is directly due to stupid-assed government regulations that are based upon the fact that PWRs in this country are a byproduct of nuclear weapons programs. They *prohibit* reactor designs that include fuel recycling, using additional reactor stages to burn the 'waste' produced by earlier stages. Don't want to deal with the waste for 10,000 years? Fine. Dump it into a seafloor subduction zone, by the time it sees the light of day again it won't be any more radioactive than any other molten material that spews forth from the Earth on a daily basis.
Considering that much of high level radioactive waste has a half-life of 12,000 years
If it has a half-life that long, it's not high-level.