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Hydrogen Buses In Iceland
dapyx writes "As part of the shift away from the fossil fuels, Iceland began its switch to hydrogen-powered buses, which are now used on the streets of the capital, Reykjavik. About 70 percent of Iceland's energy is already met by green power. Iceland plans to become the first oil-free country by 2050."
Electrolysis of water, powered by geothermal energy.
Now, some people may debate exactly how 'green' hydro dams are, but they are certainly more green than fossil fuels. However, there is one strange twist here, which is somewhat offtopic: more than a few dams in Iceland, including a massive one that is currently being constructed at Karahjukar are erected for the exlusive purpose of providing power for aluminum smelters, which are not that green.
Hydrogen generation is at least a noble attempt to use some of the available electricity for slightly more eco-friendly purposes, and surely causes less polution than fossil fuels if it is powered by hydro power.
I hear there's rumors on the Slashdots
While I commend the notion, Iceland has a unique feature not mentioned in the article -- an extremely small population. According to the CIA (spare the check-your-facts comments, thanks), it is currently less than 300,000 people.
To put that into perspective, there are over 1200 CITIES in the world with more that 300,000 people. Seriously, more people live in Toledo than all of Iceland. As far as the Hydrogen economy goes, it's a start, but such a very small start. By 2050 I sure hope we're further along worldwide.
Anybody want a peanut?
Notice how both of the other replies to you used almost the exact same wording. ;) These people are all just citing the meme that originated with Addison Bain in the late 90s as if it were gospel truth - the Bain Incendiary Paint Theory (IPT).
The funny thing is, it's been incredibly well debunked:
http://spot.colorado.edu/~dziadeck/zf/L Z129fire.pd f
The main issues:
1) An electrical spark would not have had sufficient energy to ignite the paint
2) Even if there were a spark, it couldn't have jumped in the required direction (Bain indicated that it only would have worked in one direction)
3) The rate of burn of the paint is orders of magnitude too low (about 1000x), and is not "rocket fuel" by any standard. Even if it were coated with *real* rocket fuel, like used in the shuttle's SRBs, it would take 10 hours to burn. Instead, it took 34 seconds.
They address numerous other points. For example:
* You can very easily see that individual cells are burning and others not burning by the unnatural lines that the fire traces along the surface; they discuss where the cells are, and it becomes very obvious that the fire isn't spreading along the (quite continuous) surface but only spreading as new cells catch fire.
* The "color flame issue" is nonsense, because even the earliest blimps (not coated with any similar material) burned with a similar appearance (the appearance is due to the burning of the skin at such high temperatures, making it act like a glow mantle of a gas lantern).
* The tail remained level as one would expect given a huge updraft of the hydrogen that was supporting it previously and was now not only buoyant, but very hot
* The panels were not electrically isolated from each other, as called for by Bain's guesswork
* The Hindenburg had actually survived several lightning strikes in the past that burned right through the paint; plus, the Hindenburg, at the time of ignition, was wet (it was raining during approach, and was 98% humidity), making the paint even harder to ignite. The spark would have had to first vapirized the water, and then with the remaining energy ignited the paint (something lightning failed to do previously)
* Electrical current takes the path of least resistance - i.e., over the wet surface, not through the fabric. The dielectric strength of the cellulose acetate is 100kV/cm; there's no way the current would go through it.
* The energy needed to ignite the paint is 23 joules; one charged panel could have held a maximum of 0.01 joules. To get his sample to light, Bain used a bloody Jacob's Ladder on dry fabric, and even had trouble igniting it with that.
* The very reason why there are so many scraps of Hindenburg fabric available to collectors (and people like Bain) is that, once it was lifted by updrafts out of the heat of the hydrogen fire, it was insufficient to keep itself burning.
* The paint is continuous between cells (unlike Bain's mistaken conception that, because they used separate pieces of cloth, the paint wasn't continuous, and thus charges could build up). It was painted after assembly, across the whole surface.
* The wet, continuous skin, by all effective means, would be an equipotential surface. Consequently, such a spark would be perpendicular to the surface, a situation that Bain couldn't even cause to light the fabric in the Jacob's Ladder - either from the airframe to the exterior, or from the exterior to the air (coronal discharge, i.e., St. Elmo's Fire)
* The skin is not a "rocket fuel" because it has no oxidizer, which is critical to the rapid combustion of solid rocket fuels.
* Cellulose acetate (which was used) burns (relatively) poorly in air, unlike cellulose nitrate (which wasn't used) out of concerns of saftey.
* Solid rocket propellants, which it has been compared to, have about the burn rate of sparklers in atmospheric condition. However,
We're practicing our labials.
I'm not arguing one way or the other about the Hindenberg, but I would like to warn about misinterpreting this urban myth about the flow of electricity. In a parallel circuit (i.e., a circuit with different paths), electrical current will flow along all of the paths, the amount being inversely proportional to the resistance of each path. For modelling two or three dimensional objects, integrating over all of the different paths electricity can take to figure out how much current will flow through one region of an object versus another can be quite complicated.