A lot of debate about the relative merits of IFR/MSR at the link above. IMO a well-tested IFR design would be a significant improvement over what we have, but you still have flammable liquid sodium, solid fuel pellets, and you're relying on convection to provide passive cooling. A meltdown is still very possible, and in an MSR it really isn't.
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Actually NO - a meltdown in the Integral Fast Reactor is NOT POSSIBLE, every bit as much as it is impossible in an MSR.
First, the liquid sodium is held in a container such that oxygen can't get to it. Without oxygen, the liquid sodium can't catch fire.
EBR-II operated for over 4 decades without any type of mishap owing to the liquid sodium.
Yes - you rely on convection - and that's GOOD!!!. If you have a high heat capacity coolant like sodium, then natural convection can provide all the necessary cooling. Natural convection is as reliable as gravity because that is what drives it. As long as there is a heat source that needs to be cooled, and you have gravity; then you will have natural convection. EXTREMELY RELIABLE
As far as why Clinton cancelled the IFR, it was one of his campaign promises in 1992. In fact, he mentioned the cancellation in his very first State of the Union address. He attempted to cancel it in his first budget, but Congress didn't go along. However, it was cancelled in his second budget.
http://www.sustainablenuclear.org/PADs/pad0509till.html
http://seekerblog.com/2009/11/26/plentiful-energy-and-the-ifr-story-how-the-ifr-was-killed-part-2/
Before some says, "Oh that's published in a pro-nuke website..." The pro-nuke website just published it. The words were written by Dr. Charles Till, who is a scientist, not a lobbyist.
PamW
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