These studies model the total fuel cycle costs of a reprocessing-recycling system based on thermal recycling of plutonium and compare this to the total costs of an open fuel cycle with direct disposal. The range of results produced by these studies is very wide, but all are agreed that under current economic conditions the reprocessing-recycle option is the more costly. The debate is over the width of the gap. Table 1 provides results of two recent studies at either end of the range of estimates: the 1994 OECD study as interpreted by Cogema in a recent presentation; and a 1993 study by the Vereinigung Deutscher Elektrizitätswerke (VDEW). The OECD figures appear to show only a marginal difference between the relative costs of the two options, whereas the VDEW study shows that for German conditions the reprocessing-recycle option is over twice as expensive as storage-direct disposal. The main differences are the assumed cost of reprocessing and waste management, and the treatment of credits/penalties for recycling recovered uranium and plutonium. The EWI study showed a cost difference between the two options of about 25 percent.

	OECD/Cogema (1994)		VDEW (1993)1
	Closed	Open	Closed	Open
Fuel transport	0.20*	0.20	0.38	0.12
Fuel storage	-	0.62	-	1.06
Reprocessing	2.40	-	4.16	-
Spent fuel packaging	-	1.0	-	1.862
Waste storage and packaging	-	-	2.32	0.46
Waste disposal	0.22	0.38	2.32	2.32
Subtotal	2.82	2.20	9.14	5.92
Uranium credit3	-0.36	-	+0.46	-
Plutonium credit3	-0.14	-	+1.62	-
Subtotal	-0.50	-	+2.08	-
Total	2.32	2.20	11.26	5.92
*To convert any of the numbers in this table into $/ metric ton of fuel, multiply by 356.4. 1.assumes a reactor efficiency of 0.33, a fuel irradiation of 45 GWd/ t. 2. assumes fuel conditioning plant throughput of 450 tHM per year. 3.A negative entry implies a cost saving and hence a positive value attributed to recovered products.

More limited assessments have used the 'free plutonium' concept in which the cost of separating the plutonium in reprocessing is discounted.4 This picture is closer to the reality faced by utilities today, since many regard reprocessing as a sunk cost to which they are committed through binding contracts with reprocessors. It also explains why penalties are attributed to plutonium recycling in the VDEW study. Under the 'free plutonium' scenario the economics of MOX is a question of balancing the savings made in avoided fresh uranium ore purchases and avoided uranium enrichment with the additional costs of plutonium fuel fabrication. Production of MOX is more expensive than production of LEU fuel because of the added safety and security precautions needed in handling plutonium.

Assuming current and expected prices for uranium, enrichment and fuel fabrication, MOX fuel will be more expensive than LEU fuel. Even assuming the full-scale operation of large new MOX fabrication plants (Hanau, Melox), MOX fuel would cost about twice as much as LEU fuel. If reprocessing costs are all attributed to the cost of MOX fuel (uranium credits are discounted), then MOX fuel would appear to be as much as six times as expensive as LEU fuel.5 Rather than being an asset, plutonium must be seen as a liability. Even if uranium resources are conserved, it is unlikely that an economic case could be made for the large premium that would be paid with thermal plutonium recycling. All minerals are potentially valuable, but only those which are economical are exploited.

1. OECD Nuclear Energy Agency, The Economics of the Nuclear Fuel Cycle, Paris, 1994
2. I. Hensing and W Schultz, Economic Comparison of Nuclear Fuel Cycle Options, Energiewirtschaftlichen Instituts, Cologne, 1995.
3. Cogema, Reprocessing-Recycling: the Industrial Stakes, presentation to the Konrad-Adenauer-Stiftung, Bonn, 9 May 1995.
4. OECD Nuclear Energy Agency, Plutonium Fuel: An Assessment, Paris, 1989.
5. The cost of an LEU fuel assembly delivered to a nuclear reactor lies somewhere between $1000-1500/kgU. Typical MOX fuel fabrication and transport costs are about $2000-3000/kgMOX. 4 kg of LEU spent fuel need to be reprocessed to separate the plutonium required for 1 kgMOX. European reprocessing prices are now set at about $1000/kgHM, therefore the reprocessing cost associated with 1 kgMOX is about $4000.