November 24, 2007
One of the Brickmuppets' crack team of science babes runs the numbers on hydrogen and points us to this recent story about a breakthrough in bacterial hydrogen generation.
The results came as a result of experiments with the sort of microbial fuel cell described here. This design produces electricity in small amounts but its big payoff was in hydrogen, 288 percent the energy in hydrogen that was put in.
This is not quite as impressive as it sounds. For example, if one replaced all the cars with H2 it would require the generation of just over 1/3rd the energy required by all cars to fuel them. However all hydrogen schemes that don't extract the hydrogen from hydrocarbons have high energy costs, if this is scalable it is orders of magnitude more efficient and an energy producer rather than looser. That is big.It is also capable of processing waste and generating its own energy while doing it.
As a waste disposal technique this has real potential to be tremendously helpful (again, if it is scalable).
Hydrogen is unsuited for aircraft or ships but given enough cheap energy a case can be made for H2 fueled fuel cell cars. Their range would suffer,( from what I've read, about 150-200 miles is about the best one could realistically get without turning the fuel tank into a bomb) and that assumes very efficient fuel cells. If there are H2 stations everywhere, this becomes less of a problem.
However, this process, let alone any of the others, would only make sense for hydrogen production for cars if a vast amount of cheap power were available.
So, like a lot of alternate energy proposals, it is pretty much dependent on nuclear power being developed on a very large scale in this country.
Atomic power is the future.
Science babe is actually Maria from Sakura Wars. (Which I should watch at some point)
Posted by: Avatar_exADV at Sat Nov 24 00:57:23 2007 (LMDdY)
Posted by: The Brickmuppet at Sat Nov 24 12:19:26 2007 (tFEtx)
Posted by: Pete Zaitcev at Sat Nov 24 14:21:05 2007 (9imyF)
Posted by: Jerry in Detroit at Sat Nov 24 17:14:25 2007 (hk49F)
Hydrogen is not the leakiest substance, helium is. And losses won't be that great.
But even if it were, it wouldn't have any substantial environmental effect. Hydrogen is so light that released hydrogen rises rapidly. In the upper atmosphere, ultraviolet from the sun would cause molecular breakdown, resulting in production of water vapor. The quantity of new water vapor created in this way would be negligible compared to existing sources.
Posted by: Steven Den Beste at Sat Nov 24 18:01:35 2007 (+rSRq)
This is the first H2 generating system that produces more energy than it takes in.This is big even if only on an academic level. IF this method is quick enough to allow on demand production then H2 cars might make sense. The generation has to be on demand because the stuff leaks through solid steel.That IF is indeed a big one.
One neat but dubious idea for using Hydrogen is to blend it with methane to supercharge the methane and improve its energy density. Where the methane come from is, debatable, either natural gas or perhaps millions of daisy chained cows.
The big application for this process (if it has one) may well be in the sewage treatment industry.As to whether it is better than thermal depolymerization for this I can't even guess.
H2 is utterly unsuited to aircraft or ships in any event.
Personally, for cars, I like biodiesel from algae far better than this. It has good energy density (better than gasoline) and very few handling issues. Even those can be utterly eliminated if small amounts of petro diesel are blended in. Like other kerosenes it can be used in ships and aircraft. Like all biofuels, it requires energy input. Thus we need a powerful cheap source of electricity....we need atomic power.
Posted by: The Brickmuppet at Sat Nov 24 18:08:18 2007 (tFEtx)
Regards hydrogens environmental effects, I do wonder if any studies have been done on what the inevitable vast quantities of hydrogen leakage reaching the upper atmosphere might do to ozone...
Baring any unwelcome surprises from that, I think Stephen is right, the impact should be close to nil, It should reenter the water cycle or space, there would be long term effects with a component of the planets total water mass drifting off over centuries, but in centuries we should be able to grab some comets to make up the difference, and will likely have something better by then anyway.
Posted by: The Brickmuppet at Sat Nov 24 18:15:01 2007 (tFEtx)
This is the first H2 generating system that produces more energy than it takes in.
Unless you're speaking figuratively, then if they're claiming that, it's a scam. Nothing produces more energy than it takes in; that's against the rules. And you don't get to break the rules.
Posted by: Steven Den Beste at Sat Nov 24 22:06:37 2007 (+rSRq)
It generates the hydrogen biologically. There is energy being introduced via the bacteria, that for the purposes of determining the electrical bill is not counted. It does not violate the rules any more than photosynthesis does.
It does not violate the rules.
It may not ultimately be practical, but it is guilty of no crime.
Posted by: The Brickmuppet at Sat Nov 24 23:02:12 2007 (tFEtx)
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