For a long time now, I’ve been fairly annoyed with the media and political hyperbole surrounding the future use of hydrogen. Most of the attention I’ve seen seems to revolve around the (admittedly worthy) advances in the devices (fuel cells, mostly) that help us convert hydrogen into energy for use in cars, consumer devices, etc. That’s great as far as it goes, but it’s not the whole story.
Consuming the hydrogen is only one piece of the puzzle. Not only must the hydrogen be stored, transported, and distributed (no easy feat given that it’s a vapor at sane temperatures and pressures), but we have to figure out how to produce it in quantity. That’s the piece I see left out of the discussion most often. Hydrogen is not an energy source, it’s an energy carrier. It’s not something we mine out of the ground. We have to produce it. Currently, the most efficient (cheapest) way to produce it in quantity is to use a process called steam reformation to make it from natural gas. Why not just burn the natural gas? You’re going to release the carbon one way or another. Electrolysis of water sounds attractive, but where do you get the electrical energy to do the electrolysis?
Slashdot pointed me to an article (archived copy on archive.org) on the Popular Mechanics web site that I think does an excellent job of outlining the challenges and unanswered questions that come between us and developing hydrogen as a true alternative to gasoline and other fuels. It’s by no means an exhaustive scientific study, but it does something I haven’t seen before: it provides estimated numbers on the various costs involved in getting the hydrogen from various sources. Specifically, it estimates the resources and costs necessary to meet Bush’s goal of using hydrogen to replace fossil fuels in all passenger cars by 2040. It’s not really a completely fair chart. It doesn’t take into account some kind of future technological breakthrough, but what it indicates to me is that the goal depends on such a breakthrough.
By the way, what it also underscores is that we use an immense amount of oil to power our cars. I will freely admit that I’m probably a bigger fan than most of acceleration. One way or another, though, we as a nation are going to have to figure out how to cut our energy consumption. My current hypothesis: it will happen when energy finally gets expensive here. $3.00/gallon gasoline sounds bad, but we haven’t seen anything yet.
So, what am I trying to say? I think research and development on hydrogen power should continue. We may find that breakthrough (controllable fusion with a net positive energy output, making electrolysis practical, maybe?). In the meantime, though, I’m sick and tired of politicians making political hay claiming that they know how to save the world using hydrogen. The truth is we don’t know how to get there yet.