The Importance of Breeding.

In this month's Scientific American (pay per view unfortunately) there is a very interesting and educational article on the nuclear fuel cycle and what it was supposed to be vs what it is today. Here are some highlights:

The conventional thermal reactor (generation 1-3) used today only uses 5% of the available energy in the fuel, and leaves the fuel dangerously radioactive for 10,000 years.

Fast breeder reactors (generation 4) burn an additional 90% (95% total) of the energy in reprocessed fuel from thermal reactors and leave the waste dangerously radioactive for only 200 years.

Jimmy Carter banned fuel reprocessing in this country as part of his nuclear disarmament treaty with the Soviet Union (now defunct). Thereby killing any chance of building fast breeders commercially (one was built at oak ridge I believe as a engineering and research prototype, but it has since been decommissioned).

The storage technologies developed for high level waste have a design target of 10,000 years worth of containment. Containment for 200 years is therefore much easier to achieve.

So, the question in my mind is, "Why aren't we building Gen 4 plants?"

EDIT: NEI Nuclear Notes discusses this as well.