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Hydrogen Fuel Balls from a Gas Pump?
navalynt writes "New Scientist reports that the Department of Energy has filed a patent for hydrogen fuel balls. From the article 'The proposed glass microspheres would each be a few millionths of a metre (microns) wide with a hollow center containing specks of palladium. The walls of each sphere would also have pores just a few ten-billionths of a metre in diameter.' They are supposedly safe and small enough to be pumped into a fuel tank in the same manner as gasoline."
I didn't understand what the palladium was for. But from the Wikipedia entry:
Pallaium has the uncommon ability to absorb up to 900 times its own volume of hydrogen at room temperatures.
The page includes lost of other tidbits, too. I had no idea it was such a useful metal.
Cheers.
The technology is probably similar to current "sponge" type hydrogen tanks; right now you can buy a hydrogen storage tank that uses some sort of metal hydride (I forget which) that can soak up a huge amount of hydrogen, similar to this. You heat it up to release the hydrogen stored or to recharge it, similar to how you 'recharge' that volcanic rock that absorbs odors.
The stuff theoretically wouldn't leave the "tank"; this wouldn't be like going to the gas station and filling up with little 'balls' of hydrogen. Still, I agree, it's worrying. What happens when a car is involved in a serious accident that breaches the tank, and the stuff gets all over the place? Or the stuff gets contaminated with impurities and needs to be recycled?
Carbon fiber seemed like a great idea for race cars, until track workers had to start picking up bits of the stuff. Guess what? It's the same color as asphalt, and it tends to break into very sharp shards, and the particles are really nasty if you breathe them in. Ask any track worker- the stuff is a BITCH to clean up, and if you miss any, it -will- cause someone to blow out a tire.
Please help metamoderate.
I can at least speak for what happens in the Navy. Navy researchers are encouraged to file for patents, so that the govt. can license the patents to private companies.
I think it's theoretically part of a goal to do a "technology transfer" from the DoD to the private sector. But I don't see why patents need to be part of that. Patents were meant to give you a limited monopoly SO THAT THE RESEARCH EFFORT WAS A GOOD INVESTMENT. But the DoD (and taxpayers) *already* covered the cost of investment.
This seems prefectly reasonable. Patents are not always bad.
The idea goes something like this:
Technology takes time and money to develop. Unprotected ideas are of no interest to an investor, as there is no guarantee that someone else will simply walk up and make off with the idea. Patenting an idea means that you can then license it to someone who can raise the millions of dollars it takes to develop a working device, driven by the incentive to make money.
This ensures that the initial idea can actually get developed. It doesn't matter how good an idea it is, if there is no economic incentive to get it working. Otherwise it simply gets left by the side of the road.
Ideally the license deal should also return some money to the state, to the benefit of the taxpayers who initially funded the concept. It is also worth bearing in mind that the patent only lasts for 20 years, and is written in such a way that it is a full, public disclosure.
And, yes, I have worked in IP.
- These are small, *those* are _far away_
How many times have you heard of someone getting splashed by, say, gasoline in a traffic accident? From a gasoline tanker rupture? Yes, it's bad if you get a lot of liquid hydrogen on you; you'll burn any skin surface it comes in contact with for more than a second or two. It's not instantly fatal, however, and it would take a fair bit to actually kill a person. And yes, I work with cryogenic gases.
So you don't want a garrage that's just not sealed shut, you'll want one that's ventilated constantly, even in winter. Otherwise it can jolly well blow up.
The lower explosive limit (LEL) for hydrogen gas is 18%. (For comparison, the LEL for methane (natural gas) is 5.7%, and the LEL for propane is 2.1%.) You'd need to boil off quite a bit of hydrogen to get to that level, even in a perfectly-sealed garage. Just punch a duct through to the outside from the high point in the garage (and another somewhere else to let fresh air in) and you should be good to go. Or park in the driveway.
E.g., the problem is made worse by the fact that hydrogen has no colour or smell of its own, so you can't _know_ if you've walked into a room full of it or not. Gasoline, for all its other problems, does have a smell.
Many other fuel gases lack a perceptible smell, too. Trace amounts of an odorant chemical (ethyl mercaptan) are added to propane and to natural gas so that leaks can be detected. This is very much a solved problem.
E.g., worse yet, it also _burns_ with an invisible flame, so you could walk into a jet of flame from a punctured hose or tanker that did ignite, and not even know it until you get burned by it. Again, you can handwave that as _unlikely_, but it's a very real problem and given hundreds of millions of cars, somewhere it will eventually happen.
I'll take the handwaving, thanks. Yes, hydrogen is a different fuel and has some different failure modes. One expects that commercial handlers of hydrogen are trained to anticipate and defend against the hazards associated with its use, just as they are trained in proper bonding and grounding and ventilation where they handle gasoline. If there are occasional freak accidents, hey, it happens. Getting rid of gasoline will cut down on certain other classes of accidents--the guys who try to light a barbecue with gasoline, for instance.
And so on. And, yes, I'd be interested to know how these palladium balls address those problems. E.g., will it actually make the energy density worth it, or just dillute it some more?
This is rather the crux of the matter, actually. Palladium can absorb up to 900 times its weight in hydrogen gas. Under moderate pressure, it will hold it indefinitely. No cryogenics required. It neatly addresses a lot of the safety concerns in your diatribe. The downside is that it's hideously expensive.
~Idarubicin
Now let us do a full cycle efficicency calc for the fuel cell. Starting with natural gas heated and cracked into H2, the efficiency is 60%. i.e. the H2 has 60% of the heat content of the natural gas we began with. Fuel cells efficiency is 80%. i.e. 80% of the heat content of H2 is available as electricity. There is no gear box. Electric motors convert electriciy to mechanical energy at >99% efficiency. Over all efficiency is 48% of the heat content of natural gas is available to the wheels of the car. This is already more than twice the efficiency of the gasoline energy to brake-horse-power to the wheels conversion.
The IC engine systems are at the pinnacle of their efficiency over 100 years of research and development and tinkering. The CH4 -> H2 reforming and H2->electricity fuel cell technology has barely started now [*]. Their efficiency will improve over the coming decades. Throw in the assorted facts like, 15% of the energy in the crude oil is spent in extracting it, refining it and distributing it or 80% of US Gas stations can be connected to the natural gas grid and reform CH4->H2 on site. The future of fuel cells is bright. They will win.
How soon can the US SUV fleet switch to H2? Well, in 1940 the entire locomotive fleet of USA was external combustion steam engines (6% overall efficiency energy_to_wheels/heat_of_coal). The diesel-electric hybrid locomotives had overall efficiency of 15% those days. By 1955, steam locomotives were dead.
[*] The principles of fuel cells are as old or even older than IC engines, but the large scale R&D effort has not yet been directed towards fuel cells and reforming CH4 compared to the R&D money poured into IC engines over the last century.
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact