Assessment of the Anticipated Environmental Footprint of Future Nuclear Energy Systems. Evidence of the Beneficial Effect of Extensive Recycling

Abstract

Abstract:In this early 21st century, our societies have to face a tremendous and increasing energy need while mitigating the global climate change and preserving the environment. Addressing this challenge requires an energy transition from the current fossil energy-based system to a carbon-free energy production system, based on a relevant energy mix combining renewables and nuclear energy. However, such an energy transition will only occur if it is accepted by the population. Powerful and reliable tools, such as life cycle assessments (LCA), aiming at assessing the respective merits of the different energy mix for most of the environmental impact indicators are therefore mandatory for supporting a risk-informed decision-process at the societal level. Before studying the deployment of a given energy mix, a prerequisite is to perform LCAs on each of the components of the mix. This paper addresses two potential nuclear energy components: a nuclear fuel cycle based on the Generation III European Pressurized Reactors (EPR) and a nuclear fuel cycle based on the Generation IV Sodium Fast Reactors (SFR). The basis of this study relies on the previous work done on the current French nuclear fuel cycle using the bespoke NELCAS tool specifically developed for studying nuclear fuel cycle environmental impacts. Our study highlights that the EPR already brings a limited improvement to the current fuel cycle thanks to a higher efficiency of the energy transformation and a higher burn-up of the nuclear fuel (−20% on most of the chosen indicators) whereas the introduction of the GEN IV fast reactors will bring a significant breakthrough by suppressing the current front-end of the fuel cycle thanks to the use of depleted uranium instead of natural enriched uranium (this leads to a decrease of the impact from 17% on water consumption and withdrawal and up to 96% on SO x emissions). The specific case of the radioactive waste is also studied, showing that only the partitioning and transmutation of the americium in the blanket fuel of the SFR can reduce the footprint of the geological disposal (saving up to a factor of 7 on the total repository volume). Having now at disposition five models (open fuel cycle, current French twice through fuel cycle, EPR twice through fuel cycle, multi-recycling SFR fuel cycle and at a longer term, multi-recycling SFR fuel cycle including americium transmutation), it is possible to model the environmental impact of any fuel cycle combining these technologies. In the next step, these models will be combined with those of other carbon-free energies (wind, solar, biomass . . . ) in order to estimate the environmental impact of future energy mixes and also to analyze the impact on the way these scenarios are deployed (transition pathways).

External-Cost Estimation of Electricity Generation in G20 Countries: Case Study Using a Global Life-Cycle Impact-Assessment Method

“…Nuclear systems are proven to have a small impact on carbon dioxide emissions and air pollutants [21]; however impacts (land use and resource consumption) occur during the mining and enrichment of uranium and also due to the water required to create the steam needed for electricity generation and to cool the reactors during operation [22]. Nuclear waste may also contribute to ionizing radiation [23].…”

Selective Extraction of Americium from Curium and the Lanthanides by the Lipophilic Ligand CyMe4BTPhen Dissolved in Aliquat-336 Nitrate Ionic Liquid

“…Therefore, the separation of americium alone from the HAR and re-use in fast neutron reactors would be beneficial for a more sustainable management of the rather scarce underground high level nuclear waste repository. [4,5] The separated americium inventory could in principle be very efficiently reduced as innovative new fuel in dedicated minor actinide burners such as Accelerator-Driven Systems. [6][7][8] The incentive for separate management of curium from americium relates to the high neutron emission of the curium isotopes that would render transmutation target fabrication of both Am and Cm combined in a single fuel type very difficult.…”

Batch Tests for Optimisation of Solvent Composition and Process Flexibility of the CHALMEX FS-13 Process

“…Molybdenum concentrations ranged from 3.4-6.2 mM in the various raffinates and Mo had an average extraction percentage over 50%. Molybdenum typically exists as MoO 4 2in spent nuclear fuel solution, and is extracted by TBP at higher TBP fractions. [31,56,57] Goletskii et.…”

“…Through this process, not only the amount and volume of long-lived, highly radioactive waste is minimised, the need for uranium mining is also significantly decreased. [3,4] The latter has a huge environmental footprint on nonradioactive indicators, such as atmospheric pollution, greenhouse gases, and water consumption.…”

“…The latter, the CHALMEX process, differs by selectively co-extracting the actinides from spent nuclear fuel, thus potentially reducing the number of process steps. [17,18] A bis-triazinyl-bi-pyridine molecule has been developed for extracting trivalent and pentavalent actinides: 6,6′´-bis (5,5,8,8-tetramethyl-5,6,7,8-tetrahydro-benzo- [1,2,4]triazin-3-yl)- [2,2′]-bipyridine (CyMe 4 -BTBP, Figure 1a) with a good An(III)/ Ln(III) selectivity. [19] A separation factor of over 100 was achieved for the separation of americium from europium.…”