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Hydrogen Won't Save Our Economy
anaesthetica writes "Physorg.com is featuring a story asserting that hydrogen is economically infeasible as a replacement for our current energy sources. The premise is that isolating and converting hydrogen into a usable energy source takes up a great deal of energy to begin with, and that subsequently converting that hydrogen fuel into usable energy results in an overall efficiency of only about 25%. Apparently, the increasing scarcity of water is going to make hydrogen too costly and just as politicized as oil." From the article: "[Fuel cell expert Ulf Bossel's] overall energy analysis of a hydrogen economy demonstrates that high energy losses inevitably resulting from the laws of physics mean that a hydrogen economy will never make sense. The advantages of hydrogen praised by journalists (non-toxic, burns to water, abundance of hydrogen in the Universe, etc.) are misleading, because the production of hydrogen depends on the availability of energy and water, both of which are increasingly rare and may become political issues, as much as oil and natural gas are today."
Sugar, like most other forms of easily accessible energy, is dangerous stuff. It only seems harmless since complex mechanisms have evolved to deal with it. Sugar is hydrophilic and will kill microbes that come in contact with it by dehydrating them. It will also destroy cells that contain too much of by osmosis. Your body needs to keep the level of sugar in the bloodstream within very tight limits, or bad things will happen.
(Yeah, I know. Completely offtopic.)
You didn't read the article. Hydrogen is just a 25% efficient battery. We already have much better batteries.
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This is the only thing hydrogen can do. We store energy by producing hydrogen, and then release it when we want to use it. It's never been proposed that hydrogen will magically solve the energy problem, just that it might be a good way to store/transport what energy we do produce.
The study's claim is that this is not a good idea, since the two step chemical process is simply too inefficient.
Has anybody seen that documentary movie "Who Killed the Electric Car?" In it, they look into hydrogen vehicles and the auto industry's support for it, but get a technician involved to admit that these machines are nowhere near being available to the public. This idea, along with Bush's much vaunted "hydrogen economy", is nothing more than a white elephant -- a strategy for getting the public think that the industry is doing its best, while in actual fact hydrogen powered vehicles are a dead end. They pay lip service to the idea by investing few million a year into their hydrogen research projects, while in the mean time moving along with business as usual.
As the movie points out, electric cars are the real answer: they're simple, cheap, fast, efficient, convenient and low maintenance, so there's absolutely no need for hydrogen to enter the equation. Hydrogen just makes these cars more complicated and less efficient. The only thing holding back the electric car is the will of the industry. For instance, Chevron holds the patents for one of the most promising battery technologies, but they specifically forbid the current manufacturer to sell them for use in private vehicles (only public transport).
I suppose you could argue that the auto manufacturers the oil companies are only acting in the best interests of their stock holders, and that's probably true, but at this rate they might as well be evil.
I've been charging batteries with efficiency of around 85%. High-efficient switched mode chargers can reach even higher numbers.
And if the target load is much smaller than the internal battery impedance, you get near 100% efficiency using the stored energy, at least at battery's terminals.
Battery is not a waveguide. You don't match its impedance to the load (and lose half of the energy if doing that)!
Alcohols also need to be made, although there is at least a slight energy gain in the process (stored solar energy in the plants you ferment). Converting a perfectly viable fuel like Alcohol into hydrogen is pointless: You lose energy in the conversion and you still release the carbon into the atmosphere.
You are correct in saying that hydrogen is rarely produced by electrolysis due to energy consumption. Do you know how it's really made? Reforming natural gas - a fossil fuel! Congratulations, you've managed to shift our dependence on fossil fuels from crude oil to natural gas (which is even more scarce) while reducing the overall energy yield from the raw fuel and still not reducing carbon emissions.
Metal hydride storage uses some pretty expensive, toxic and dangerous materials and still does not achieve the hydrogen storage density of more common and safer-to-handle fuels such as gasoline and diesel fuel.
It's a trifecta of failure.
=Smidge=
Clean potable water is surprisingly hard to access in quantities outside the developed world (and becoming far more scarce daily). Aquifers in the US are sinking (some with alarming speed). You generally can't just stick probes in the ocean and create industrial levels of hydrogen.
Degaussing scares the bad magnetism out of the monitor and fills it with good karma.