Progress Energy announces intention to apply for nuclear permit

Thanks for the information, I had run into this during google searches, here is an extract:

"Russia has experimented with several lead-cooled reactor designs, and has used lead-bismuth cooling for 40 years in its submarine reactors. Pb-208 (54% of naturally-occurring lead) is transparent to neutrons. A significant Russian design is the BREST fast neutron reactor, of 300 MWe or more with lead as the primary coolant, at 540°C, and supercritical steam generators. The core sits in a pool of lead at near atmospheric pressure. It is inherently safe and uses a U+Pu nitride fuel. No weapons-grade Pu can be produced (since there is no uranium blanket), and spent fuel can be recycled indefinitely, with on-site facilities. A pilot unit is being built at Beloyarsk and 1200 MWe units are planned.

A smaller and newer Russian design is the Lead-Bismuth Fast Reactor (SVBR) of 75-100 MWe. This is an integral design, with the steam generators sitting in the same Pb-Bi pool at 400-480°C as the reactor core, which could use a wide variety of fuels. The unit would be factory-made and shipped as a 4.5m diameter, 7.5m high module, then installed in a tank of water which gives passive heat removal and shielding. A power station with 16 such modules is expected to supply electricity at lower cost than any other new Russian technology as well as achieving inherent safety and high proliferation resistance. (Russia built 7 Alfa-class submarines, each powered by a compact 155 MWt Pb-Bi cooled reactor, and 70 reactor-years operational experience was acquired with these.)"

http://www.uic.com.au/nip60.htm
http://nuclear.inl.gov/gen4/lfr.shtml

Similar designs in the US have been done (on paper) by Argonne and other researchers. If you google for
STAR-LM, SSTAR, EPBR, 'nuclear battery' (UC Berkeley design), you'll find more info.

more links:

http://www.rae.anl.gov/research/ardt/hlmr/

"STAR-LM"
"The small modular reactor is envisioned to be liquid-metal-cooled and run up to 30 years without requiring fresh fuel. At that point, the fuel would be cut out for burial or for reprocessing. The fuel feedstock could be natural or depleted uranium, or the reactor might run on excess weapons-grade plutonium."

"The reactor would have a sealed core -- a feature to make it more proliferation-resistant. It also would have passive safety features, so it would go into a safe shutdown mode without human intervention."

The designs seems simple enough and with enough margins on operation and safety that IMHO they are the most promising form of "fast" reactors. I do think eventually we will need both 'once-through' and 'fast' breeder type reactors. What's really neat is that IMHO these fast reactors could probably build at LOWER cost than a PWR/BWR, due to lower complexity of system overall.

Key points:
1. The core sits in a pool of lead at near atmospheric pressure. The kind of corrosion and need for active safety measures that pressurized systems creates goes away. lead is liquid over a huge range of temperatures.
Moreover, if you use air or CO2 instead of steam to power the turbines, you would avoid the corrosive components and extreme pressures of current nukes entirely. All but the reactor core would be similar to a gas turbine plant.

2. "Pb-208 (54% of naturally-occurring lead) is transparent to neutrons. " This means you can have a 'fast' reactor, ie, breeder type that uses the fuel much more efficiently.
The problem with 'fast' reactors is that they seem more dangerous due to margins of going super-critical.
But this is the beauty of Pb: the high melting point and
lack of above atmospheric pressure make this
Unlike sodium it wont create fires if exposed to air. So it has advantages over sodium-cooled.

3."Natural convection heat transport at all power levels eliminates the need for main coolant pumps further contributing to cost competitiveness."
I feel this design and the PBMR are probably the safest designs of nuclear power plants, because of passive heat removal and margins.

4. Experience of Russians is a valuable validator of the concepts:

"A smaller and newer Russian design is the Lead-Bismuth Fast Reactor (SVBR) of 75-100 MWe. This is an integral design, with the steam generators sitting in the same Pb-Bi pool at 400-480°C as the reactor core, which could use a wide variety of fuels. ... (Russia built 7 Alfa-class submarines, each powered by a compact 155 MWt Pb-Bi cooled reactor, and 70 reactor-years operational experience was acquired with these.)"

5. Long life of the fuel in the reactor is positive for nuclear proliferation reasons, nuclear waste reasons and operating cost reasons.

So I think we should develop this design. IMHO, it's a winner.

"So what are the construction/operating-cost differences between these and the helium gas-turbine designs? One thing's for sure, in the US proliferation is not a worry."

Not sure. Jimmy Carter got rid of our fuel reprocessing because of proliferation concerns. The US wasting valuable fuel did not prevent North Korea and Pakistan from getting the bomb, with Iran in a race with France to become the second Islamic nation with the bomb. It may have even helped by forcing us to use more oil and thus giving the enemy more revenue.

Four years ago today we were struck by radical Islam. Our enemy depends upon oil revenue but we seem to lack the will to wage war upon our enemies economy even though they targeted ours. Our troops are doing their part in the war, but the home front does not wish to share the sacrifice. Guns and butter wars have not turned out very well for America. If our enemy questions our national will he may be justified in his doubts.

Consider that on December 7th, 1945 our enemies had already been defeated, his cities laid to waste. Here it is the fourth anniversary of 911 and define the enemy as terror, we lack even the will to name our enemy and thus declare war upon his tactics!

Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.