I’ve been following the renewed interest in nuclear power.

While I (as a muttonheaded 16 year old who thought George McGovern had most of the right ideas) joined the herd in panicking about nuclear power after Three Mile Island, it’d seem rumors of the death of nuclear power were premature.  Word filtered back through the literature as far back as the late eighties about German and Swedish advances in nuclear physics that made meltdowns physically impossible – which sure sounded good.

Anyway, I thought about that when read this bit in Pop Mech a while ago.

As a result, the frontrunner for the initial $1.25 billion demonstration plant in Idaho is a helium-cooled, graphite-moderated reactor whose extremely high outlet temperature (1650 to 1830 F) would be ideal for efficiently producing hydrogen. There are a couple of designs that could run that hot, but the “pebble bed,” so named for the fuel pebble that Weaver holds, is attracting particularly intense interest.

A typical pebble-bed reactor would function somewhat like a giant gumball machine. The design calls for a core filled with about 360,000 of these fuel pebbles–“kernels” of uranium oxide wrapped in two layers of silicon carbide and one layer of pyrolytic carbon, and embedded in a graphite shell. Each day about 3000 pebbles are removed from the bottom as fuel becomes spent. Fresh pebbles are added to the top, eliminating the need to shut down the reactor for refueling. Helium gas flows through the spaces between the spheres, carrying away the heat of the reacting fuel. This hot gas–which is inert, so a leak wouldn’t be radioactive–can then be used to spin a turbine to generate electricity, or serve more exotic uses such as produce hydrogen, refine shale oil or desalinate water.

The pebbles are fireproof and almost impossible to use for weapons production. The spent fuel is easy to transport and store, though there still remains the long-term problem of where to store it. And the design of the nuclear reactor is inherently meltdown-proof. If the fuel gets too hot, it begins absorbing neutrons, shutting down the chain reaction. In 2004, the cooling gas and secondary safety controls were shut off at an experimental pebble-bed reactor in China–and no calamity followed, says MIT professor Andrew Kadak, who witnessed the test.

We should be cranking these things out like X-Boxes.

Naturally, read the whole fascinating thing.

And if that works, maybe we can go for one of these.

(And remember which party is still married to those thirty-year-old “No Nukes” shirts).

This entry was posted by by Mitch Berg on Wednesday, October 1st, 2008 at 12:11 pm and is filed under Geekery. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.