|Fig. 1: Light Water Reactor Components. (Source: Wikimedia Commons)|
A light water reactor is a water-cooled reactor that uses water as a coolant, producing heat from nuclear fission. This specific type of coolant system uses light water instead of traditional heavy water. By nuclear fission, light water reactors produce heat and further generate energy. Nuclear power using light water reactors has become very popular the past few decades, and continues to increase in popularity despite many concerns surrounding it. Demand for electrical energy is supposed to increase by 20% in the next 20 years, while nuclear power plants are reaching the end of their 60-year operating licenses.  If operation of these plants is not improved and sustainability does not increase, there will be a decline in the total electrical energy from nuclear power as result. If light water reactors are going to be a viable option for the future, sustainability must be at the forefront of discussion.
Light water reactors inherit many issues in their own right, both politically and in terms of sustainability. Many technological advancements and methods must evolve place in order for increasing sustainability to be made of these reactors. Materials and systems, structures, and aging components in the environment such as cables must improve. One of the more concerning problems exists because of the reactors having a 60-year license. Concerns arise when trying to decide how to maintain sustainability in these reactors so that they not only last longer while sustaining their make up, but also to make them more cost efficient and innovative so that they can surpass their license. Another problem exists when trying to solve the worlds energy problem through nuclear power, and that problem exists within uranium sources.  Getting rid of the enigma that there is not a long-term future in nuclear reactors is crucial, but can only be proven if sufficient resources of uranium are established.  Uranium resources have to become less sparce and we must estimate uranium requirements for reactors before carrying on unless technologies for extensions of uranium are efficiently introduced.  As demands continue to increase for energy along with growing awareness of environmental impacts, there must be debate on how to best achieve sustainable, affordable, and environmental solutions to the generation and utilization of electricity in the future. 
Despite the problems surrounding light water reactors, sustainability is feasible and is well worth the challenge. Several steps must take place in order for improving sustainability and ensuring a brighter future for light water reactors. First of which is to deal with the pressing issues at hand directly and efficiently. Increasing awareness and research surrounding sustainability and technology, along with increasing knowledge about the reactors themselves will help predict and further understanding on how to predict and measure change about the reactors structures as they age. Developing scientific basis for understanding and predicting environmental effects on the reactors and materials in the nuclear power plants will add to better sustainability, further decreasing aging and degradation.  In turn, all of these steps to enhance the reactors and promote better sustainability must be taken with both economical and safety concerns in mind. Developing new digital technologies will also provide monitoring capabilities to help with these safety concerns, ensuring safe, reliable, and economic operations of such nuclear power plants. Technological advances will ultimately lead toward towards sustainable nuclear fuel through closed-fuel cycles, along with advancements in fuel development.  Economically, developing high performing and higher burn-up fuels would directly advance nuclear fuels .  Ensuring there is enough uranium on the ground to sustain light water reactors in the future must be the number one priority for the future. As plants continue to age, either more plants must arise or plants must become more sustainable to outlast older plants past their operating licenses. Ultimately, investing cost and research is crucial for the success of sustaining light water reactors in the future.
Without emphasis on sustainability, light water reactors will fail to exist in the future. Unlike many other resources that have promising futures with an abundance of resources, light water reactors do not have that luxury. As demands increase for electrical power, so will demands for resources to produce such power that is produced trough light water reactors. In order to flourish there must be a focus to improve technology, safety, productivity, and ultimately long term sustainability and promise. Longer lifetimes and sustainability are vital and must continue to be at the forefront of concern and progress in this realm of nuclear energy. Fortunately, the promising opportunities outweigh the pressing concerns.
© Tyler Thorne. The author grants permission to copy, distribute and display this work in unaltered form, with attribution to the author, for noncommercial purposes only. All other rights, including commercial rights, are reserved to the author.
 "Light Water reactor Sustainability Program," U.S. Department of Energy, April 2013.
 D. Pevec, V. Knapp and K. Trontl, "Long Term Sustainability of Nuclear Fuel Resources," in Advances in Nuclear Fuel, ed. by S. T. Revankar (InTech, 2012).