Wednesday 9 November 2016

Nuclear waste, "constipation", and Jim Green.

Jim Green came out of his, hopefully, 'environmentally friendly' Batcave again. The SuperAussie leading Friends of the Earth, Oz, argues against fast reactors once again. For an anti-nuclear activist who claims to be protecting the environment, Jim surely has an obsession with fast reactors. Reactors which don't really exist anywhere, so can't be causing any environmental harm. Jim previously, wrongly, said that fast reactors were used by France to make lots of plutonium for their weapons programme ("340 kg of plutonium for WMD"). I debunked that long ago here.

Let me look at some of his points. The Japanese Monju fast reactor now closing was a loop-style reactor. Liquid metal fast breeders (LMFBR) favoured by Gen IV fans (like me) are basically pool-style reactors. Loop and pool, chalk and cheese, work in very different ways when used as fast breeders. The GE-Hitachi PRISM and Russian BN-XXX reactors (e.g. BN-800) are pool types. The GE-PRISM is based on the Integral Fast Reactor, IFR, research from 1984 – 1994, in the USA which had an excellent safety record with estimable clean energy and environmental goals.

A fast reactor with a cheap, easy way to recycle fuel, can leave only 1200 part, or 0.5% of the waste of conventional light water reactors (LWR), which run on low enriched uranium (LEU). USA developed such cheap, easy recycling technology over 2 decades ago during IFR research. It’s called “pyroprocessing”, but the idea depends upon separating waste using electricity. Like a battery in reverse. Something called electro-deposition.

Fast reactors which leave hardly any waste are bad news for anti-nuclear power activists like Jim Green. Because one of their core strategies is to “constipate nuclear power”, by preventing waste disposal. Far harder when future waste is only 0.5% current waste. Hence the effort anti-nukes put in to spread alternative lies. For example the lie that fast breeder reactors lead to A-bomb proliferation. This is another point Jim Green previously made elsewhere.

There are good reasons fast breeders, like PRISM, can leave only 0.5% the waste of a conventional reactor, for the same electricity made.

  1. Nearly 90% of the radioactive waste from nuclear power begins in fuel manufacture. The depleted uranium (DU), from enrichment, can’t be used by conventional light water reactors (LWR). A fast breeder reactor can use DU for its fuel. To be fair to Jim - he basically ignores the issue of DU.
  2. Anything from 95% to 96% of the fuel going into a LWR is unused when it exits. Cheap pyroprocessing makes it economical to put this fuel back in; leaving only radioactive fission products as waste.
  3. If the fission products are stored for 50 years, half of it is deactivated, by decay. Only the longer decaying, still radioactive material need be disposed of as waste. So we could, actually, get the nuclear waste down to below 0.25%, or 1400 part of what it currently is. But only if we build breeder reactors.
  4. A PRISM reactor is more efficient in using heat generated than a LWR. That's because a PRISM runs at a higher temperature (> 500ºC) compared with a LWR (maximum ~ 330ºC). This leads to a greater temperature difference between source and sink. In the case of a PRISM, it might mean up to 10% - 20% efficiency gain. E.g. For the same electricity output, a PRISM may make over 10% less fission products than a PWR.

That’s one reason why real environmentalists favour nuclear power, but fake environmentalists like Jim Green oppose it. Disagree with me? You could always try asking Jim Green why he opposes nuclear power. Supposing you can take the torrent of censorship, abuse and personal attacks his supporters will direct at you.

Reference

  • See Plentiful Energy, for a description of the IFR, and pyroprocessing. Especially chapters 5 and 13 covering "Choosing the Technology", and "Economics".
  • Watch Dr. Roger Blomquist, of U.S. Argonne National Laboratory, describe the cost of pyroprocessing as only 17 that of current nuclear fuel reprocessing such as PUREX.
  • 'constipate nuclear power'! Why is there no link to environmental propaganda here? Because this is supposedly a secret policy of theirs they don't admit to. Greens who've actually constipated nuclear power use this phrase among themselves to describe what they do. We know that from ex-greens who did it.

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