Is nuclear fission a sustainable source of energy?

Abstract

During this century, humankind must deal with increasing demand for energy and the growing impact of burning fossil fuels. Nuclear power, which presently produces 14% of global electricity, is a low-carbon-emissions alternative. However, the sustainability of nuclear power depends on the amounts of uranium and thorium available, the economics of their recovery from ore deposits, and the safety and security of nuclear materials. Unlike combustion of hydrocarbons, which determines the amount of fuel needed for a given amount of energy, nuclear reactions can create additional fi ssile isotopes. Hence, the choice of nuclear fuel cycle profoundly affects the size of the nuclear resource, as well as nuclear waste management and the risk of proliferation of nuclear weapons. We argue that uranium resources, identifi ed and yet to be discovered, could sustain increases in nuclear power generation by a factor of two or three through the end of this century, even without advanced closed-fuel-cycle technologies. Uranium resource estimatesEvery two years, the International Atomic Energy Agency (IAEA) and the Nuclear Energy Agency of the Organization for Economic Co-operation and Development jointly publish global estimates of the uranium available in various categories of resources in the "Red Book" 4 ( Table I ), based on mining-company estimates. In 2009, ∼ 4000 kt of uranium was classifi ed as being in reasonably assured resources (RAR), for which there is direct geological evidence. Knowledge of existing deposits leads with high confi dence to the location and size of an additional 2300 kt in inferred resources (IR). Together, these two classes constitute identifi ed resources , and their distribution is shown in Figure 1 . The world's largest known deposit, Olympic Dam in South Australia, is estimated to have 1447 kt of uranium in RAR Whereas Canada and Australia have most of the present resources and active mines, Russia and Kazakhstan have the greatest potential for increased production. This map does not include information on either price or undiscovered resources. IR (2010). 6 Other deposits are much smaller, some having IR of 100-300 kt of uranium and many more with less than 100 kt.Beyond these identifi ed resources, the Red Book estimates an additional 10,400 kt of uranium in undiscovered resources. Extrapolations concerning the existence of these deposits are based on evidence in known uranium provinces where there is either some direct evidence ( prognosticated ) or similarities in geologic occurrence ( speculative ).In addition, there are unconventional sources of uranium, such as the tailings left behind at gold or uranium mines. Elevated uranium concentrations also occur in phosphate deposits and black shales. Uranium resources in phosphates are estimated to be more extensive than conventional uranium deposits. Extracting uranium as a byproduct of the production of phosphate-based fertilizers could yield up to roughly 10 kt per year, depending on the average ore concentration and world fertilizer demand. ...

Ion adsorption and diffusion in smectite: Molecular, pore, and continuum scale views

“…Nuclear fission produces 14 % of the world's electricity supply and could contribute ~15 % of 24 CO 2 abatement efforts required to stabilize global CO 2 emissions over the next 50 years (Pacala 25 and Socolow, 2004; Englert et al, 2012). The viability of nuclear energy as a CO 2 abatement 26 technology, however, relies in part on the demonstration that geologic storage facilities can 27 isolate high level radioactive waste (HLRW) on time scales commensurate with the decay of 28 long-lived radioactive fission products, on the order of 10 6 years.…”

Development of 225Ac Radiopharmaceuticals: TRIUMF Perspectives and Experiences

“…New 226 Ra sources could be extracted from the waste of current uranium mining operations. Approximately 50 thousand tonnes of uranium ore is mined each year [50], from which 226 Ra is separated and disposed of as waste. With the potential to extract 257 mg of 226 Ra from each tonne of U 3 O 8 [39], this amounts to about 12.85 kg of 226 Ra waste per year.…”

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Agenda Pembangunan PLTN Dan Pencapaian Ketahanan Listrik

“…Hal ini sejalan dengan pandangan umum bahwa PLTN memiliki keunggulan sebagai alat mitigasi ancaman perubahan iklim, efisiensi sumber daya dan ketahanan energi. Hal ini karena siklus hidup emisi GRK nuklir sama rendahnya dengan angin, jumlah daya listrik yang dihasilkan, bahan baku uranium yang melimpah, dan risikonya dibesar-besarkan (Kessides, 2010;Englert, et. al.…”