Studies on fast reactors have historically concentrated on their capability of using plutonium produced in thermal reactors as initial fuel, and subsequently their capacity to produce electricity while breeding new plutonium fuel from the uranium they consume. Since such breeder reactors are unlikely to be deployed at a large industrial scale in the medium term, an excess of plutonium from thermal reactors is accumulating. Consequently some countries are seeking to balance their stockpile of separated plutonium by recycling it in thermal reactors. However, there is a limit to the number of times plutonium can be recycled this way, because its isotopic quality degrades with every cycle. For this reason, fast reactors which are configured for net plutonium burning, are being considered for the medium term as means for reducing the stock of plutonium of variable isotopic quality.
In order to understand better the physics of such fast burner reactor systems, benchmark studies were specified for four scenarios: one for an oxide-fuelled fast reactor and three for a metal-fuelled one.
This report covers the benchmarking of codes and data sets on beginning-of-life configurations of oxide-fuelled and metal- fuelled fast plutonium-burner reactors. Discrepancies among participants' solutions for the neutron balance and its components are identified. Methods required for obtaining satisfactory results are also identified. Methods required for obtaining satisfactory results are also identified as are requirements for supporting critical facility measurements.