With the rapid depletion of fossil fuel and the increasing significance of global warming problem, many alternative resources are being discussed as future options for sustainable energy. Among them, nuclear power, despite its high efficiency and relatively low cost of production, has been associated with many concerns including waste management, supply channel security, operational safety and proliferation.
From the perspective of where we will be in 2050, nuclear energy needs to consistently provide 8 - 10 TW of power in order to contribute to our future energy demands. To get 10TW of power from nuclear energy, we need about 10,000 nuclear power plants, which means that we need to build at least one power plant in every two days until 2050.  Since we have 439 operating nuclear reactors around the world, we need about 20 times the number of reactors we have currently, which is a daunting challenge to face.  However, as uranium is not an unlimited resource, with this level of production, our uranium resource base would be depleted in 10 years, which means nuclear energy will not be able to be the main substitute for fossil fuel. 
There are three main concerns regarding nuclear energy: operational safety, nuclear waste management and risk of proliferation.
Operational: As nuclear technology is inherently dangerous, operational safety is a big concern when discussing nuclear energy. The fact that nuclear plants can shut down even with the slightest suspicion of a malfunction proves how rigid safety standards need to be. While there are not any proven correlations between cancer deaths and plant operations, big disasters such as Fukushima explosion will always remain as a possibility.  Nevertheless, the most current and advanced nuclear power plant designs use inherently safe technologies with drastically improved safety characteristics, which will eventually guarantee reliability and safety of nuclear operations. 
Waste Management: The radioactive by-products of nuclear fission must be isolated in order to avoid significant harm to the human environment. In their long-term disposal site, nuclear waste has to be stored for periods up to 1 million years.  Compared to coal and oil-based power plants, the volume of nuclear waste is trivial and hence the cost of disposal is also not a significant issue.  However, public and political opposition to waste disposal has delayed efforts to create deep geological repositories.  Hence, waste management problem is not simply technical, but also institutional and political.
Proliferation: Problems related to nuclear proliferation is considered as the most sensitive and difficult to solve. According to Toth and Rogner, "events in recent years have revealed loopholes in the current international agreements and their enforcement mechanisms and make it obvious that the major challenge nuclear energy is facing today is to provide an impermeable solution for managing the nuclear fuel cycle in order to prevent proliferation and to eliminate the risk of misusing nuclear material."  While is this is not a good space for an in-depth discussion of potential solutions, managing these risks will involve leveraging technical advancements and regulation enforcements.
The future of nuclear power as a major source of energy will depend on whether it can overcome the challenges of operational safety, proliferation and waste management. While the third generation power plants are significantly safer than previous ones, their cost has to be driven down in order to be economically competitive.  New nuclear power plants operate at $1700-$3100/kW, which cannot compete against natural gas technology, especially when the gas infrastructure is already in place. However, the economics of nuclear energy can be competitive when coal or natural gas's infrastructure is not in place, since they have to be transported over long distances or through pipelines.  In terms of waste management, there have been advances in safe waste disposal technology, with one solution that involves using deep geological repositories. Nevertheless, for a long-term solution, we need to take a more innovative approach to this problem by developing technology that fundamentally reduces the amount of waste produced. 
While nuclear power cannot substitute fossil fuel entirely and become the sole sustainable energy resource, it can play a significant role in decarbonizing the production of electricity. Although we face significant challenges that are constraining the prospects for further development, nuclear power should be developed as a potential carbon-free energy resource in order to mitigate future problems of climate change and other environmental concerns.
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 R. Eisenberg and D. G. Nocera, "Preface: Overview of the Forum on Solar and Renewable Energy," Inorg. Chem. 44, 6799 (2005)
 L. Giusti, "A Review of Waste Management Practices and Their Impact on Human Health," Waste Management 29, 2227 (2009).
 N. Armaroli and V. Balzani, "The Future of Energy Supply: Challenges and Opportunities," Angew. Chem. Int. Ed. 45 2, (2006).
 F. L. Toth and H.-H. Rogner, "Oil and Nuclear Power: Past, Present and Future," Energy Econ. 28, 1 (2006).
 R. H. Williams, "Advanced Energy Supply Technologies," in World Energy Assessment: Energy and the Challenge of Sustainability (United Nations, 2000), p. 273.
 S. Chu, and A. Majumdar, "Opportunities and Challenges for a Sustainable Energy Future," Nature 488, 294 (2012).
 R. Sims, H.-H. Roger, and K. Gregory, Carbon Emission and Mitigation Cost Comparisons Between Fossil Fuel, Nuclear and Renewable Energy Resources Ror Electricity Generation," Energy Policy 31, 1315 (2003).