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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)"
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.
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~ |rip/\/\aster /\/\onkey
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
A better article which goes into a bit more detail about the pellets can be found at this french website http://www.achats-industriels.com/actualites/dossi ers/269.asp/.
& u=http://www.achats-industriels.com/actualites/dos siers/269.asp&prev=/search%3Fq%3Damminex%26hl%3Den %26lr%3D/.
The google translation is available at http://translate.google.com/translate?hl=en&sl=fr
This is an interesting storage solution but to really evaluate this we need to know more about the process to extract hydrogen and the waste products involved and their potential re-uses.
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
A bit of background info found doing a quick google:
D TU_04.pdf
http://lww.kt.dtu.dk/pdf_publications/department/
Not much there but adds a bit more ligitimacy to the claims. Its a university annual report from the Technical University of Denmark, see pages 24-26.
By comparison the post office runs several propane powered vehicles around the city here. These poor performing vehicles run on a fuel with an energy density of 7.5 kwh/liter.
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
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.
I've found another (from June) article here (in french). For a long time people have been talking about ammonia as hydrogen storage, as it's quite high in energy density and is a relatively safe liquid. However, there are issues with gas expansion, pressurization and toxic fumes.
Essentially, these pellets are an ammonia storage system that stores ammonia nearly as efficiently (by weight and volume) as liquid ammonia. The above article says that they are relatively cheap to produce (initial costs of 1 euro/kilogram of material, which translates to roughly $12.88 USD for the energy equivalent of a gallon of gasoline). The article clearly states that the process is reversible, thus the base materials must be reusable. It does not state what the cost is of 'recharging' the pellets. The recharge cost would have to be at least 4x cheaper than production in order for it to be competitive with gasoline. The extraction technique is listed as 'desorption', which I imagine just means heating the pellets up and siphoning the extracted gas off. As for temperatures, and desorption rates, nothing is cited.
It doesn't state specifically how the reaction runs, but that ammonia is extracted from the pellets, which is then run through a standard ammonia converter (at temperatures of around 350 degrees celsius) to extract the hydrogen. It says the reaction runs quickly, so it's able to provide the hydrogen quickly enough.
The Amminex website has slightly more information available by clicking on the "ammonia storage" page, because it's the exact same technology as the hydrogen storage (link here)
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.
Well, on a geologic scale, gasoline and even crude oil is just an energy carrier. Plant life millions of years ago used sunlight to bond simple organic molecules into more complex ones which eventually became hydrocarbons -- effectively storing up large amounts of solar energy into a liquid form.
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.
Wrong, There are a variety of synergistic efficiencies with electric vehicles. Regenerative braking turns otherwise wasted energy back into electricity for re-use rather than throwing it away as heat. Thats why the Ford Escape hybrid gets better milage in the city than on the highway. Lighter power plant and no brakes means the car weighs less. Since the car weighs less you need less power and lighter wheels and suspension. Lower Rolling resistance wheels can be used (which are lighter. Lower power means lighter power plant . . . Repeat a few times. etc. Power generation is centralized and therefore more efficient. Oh and by the way, these cars are quiet.