BoingBoing.net is reporting today on a tabletop “hydrogen power station” that produces hydrogen from water using a standard power outlet and costs around $200. While this may sound wonderful on the surface, it merely illustrates how the notion of a “hydrogen economy” is mostly a myth, especially as it pertains to powering vehicles.
Let’s get one thing perfectly clear: hydrogen is not a energy resource. Hydrogen does not exist naturally in any sufficient quantities to make it a viable energy source, at least on this planet. To get hydrogen in any useful quantities, it must be extracted from natural gas, water or biomass, and all of these result in a net loss of energy. It is more efficient to use these fuels in their original forms.
Hydrogen is more like a battery, an energy storage medium. Unfortunately, (for practical purposes) it is a very impractical battery, with an extremely low energy-to-volume ratio. According to Wikipedia, “The energy density per unit volume of both liquid hydrogen and compressed hydrogen gas at any practicable pressure is significantly less than that of traditional fuel sources, although the energy density per unit fuel mass is higher.”
To be fair, fossil fuels are only energy storage mediums as well, but their energy was accumulated over millions of years, and is readily extracted now in a compact form. Neither hydrogen nor fossil fuels are energy sources, because the energy does not come from them, it came from the sun, the only really abundant energy source we have (not including nuclear and geothermal, which are very small players to date).
The BoingBoing article cites the Navy’s research into hydrogen-powered drones as proof of hydrogen’s future usefulness as an energy carrier. It seems more likely, however, that hydrogen is being tested in unmanned aerial vehicles (UAVs) to take advantage its light weight, and not for its ability to store a large amount of energy. The Science Daily article seems to back this up by noting the vehicles light weight and extremely small motor, only .75 horsepower, compared to traditional UAVs.
The only way that hydrogen can become truly worthwhile is if someone comes up with a way to create it from renewable energy sources, i.e. wind/solar, and store it is a form compact enough that it is comparable to current battery technology, while managing to preserve our extremely limited freshwater resources.
I’m sorry, hydrogen fans, but any way you slice it, the hydrogen economy is a myth, at least on this planet.
What do you think? Is a hydrogen economy worth pursuing? Post your opinion in the comments.
Update:I would like to clarify that, when this article refers to the “Hydrogen Economy”, it is mostly referring to the use of hydrogen to power vehicles, not other uses of hydrogen. As several readers have pointed out, there are plenty of other uses for hydrogen, and it certainly has its place as part of a basket of solutions to replace fossil fuels. These include industrial applications, such as powering fork lifts, or commercial applications, such as fuel cells for office buildings.
My central point is that hydrogen is not practical to use in powering automobiles at this time, and isn’t likely to be any time soon. Even if there comes technology that can support powering cars with Hydrogen on a practical level, it still doesn’t make sense to convert natural gas and water to hydrogen on the scale needed for these applications.
Update 2/18/10: For those of you who just can get enough of the pro/con hydrogen discussion, there’s a lively debate going on at reddit.
Update 2/19/10:As several readers have pointed out, my characterization of both hydrogen and natural gas as being “energy stores” and not “energy sources” is somewhat confusing and muddies the waters. (I will admit that sometimes my over-analytical brain wants to point out things that are interesting but tangential, and, in this case, quite semantic in nature.)
I therefore, stand corrected. For the sake of this dis discussion, both hydrogen and natural gas can be considered energy “sources”. You simply need to draw your system boundary in such a way that you only view the system after energy is stored in the medium. The main difference is that natural gas is stable under normal conditions, and hydrogen is not, reacting with other elements unless outside measures are taken.
In any case, all of this detracts from the more important debate about how efficient it is to store energy as hydrogen and then use it to power vehicles, etc., instead of some other method.
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Steve Puma is a sustainability and technology consultant. He currently writes for 3p as well as on his personal blog, ThePumaBlog, about the intersection of sustainability, technology, innovation, and the future. Steve holds an MBA in Sustainable Management from Presidio Graduate School and a BA in Computer Science from Rutgers University. You can contact Steve through email or LinkedIn, or follow him on twitter.