Reply #46: Well, sort of... [View All]

[lapfog_1]

What I'm saying is that Hydrogen is not (currently) a fuel source on earth. It's an energy storage or carrier. Oil, natural gas, coal, are also energy carriers, but the energy is already stored in them from millions of years ago (as you say, sunlight). Hydrogen is a bit different as there are few areas of naturally occurring free hydrogen. Mostly when people talk hydrogen, they think of water and electrolysis, or natural gas (which would release as a waste product, CO2). Electrolysis takes energy, and lots of it, to produce free hydrogen. That fact, along with the cost of containment, the cost of conversion back to electricity via fuel cells, and the rare materials that make up current generation fuel cells, makes hydrogen less attractive as an energy carrier than, say, batteries or ultra capacitors.

I would rather our infrastructure go all electric, with money spent on ultra capacitors when the need for "off grid" power is required (a disconnect from an electric production facility). Safely containing KWhrs of electricity is easier than containing (never mind safely) hydrogen gas, and conversion to electricity is not required. Re-charging is still an issue. But we really haven't concentrated on ultra capacitors all that much when compared to the research dollars that went into fuel cells (starting with NASA for more than 40 years).

As for power sources, there is the capturing the sun's power (solar, wind, wave), the power of a massive body orbiting close the earth (tidal power), the power of earth internal processes (geothermal), and nuclear power ( fusion, fission). If I could wave a magic wand, I'd have fusion to generate and totally reusable ultra capacitors for storage. But fusion, for as much as we've spent on it, still seems far away... However, there have been a number of posts here about Thorium fission reactors (much safer and, apparently, with radioactive waste products which are a) much smaller by volume, and b) have half lives that are fractions of the current fission reactors produce. Instead of safe storage for thousands of years, it appears from the literature that we'd only have to safely store the waste for mere decades or a century or two. And there isn't that much waste product to begin with. As a stop gap for the next hundred years (until fusion), I say let's go with Thorium nukes and as much renewables as possible for generation.

Eventually, should our species last that long, we will mine the very stars themselves for free hydrogen (or interstellar space). But that's a long ways off and we may never need it.