|Fig. 1: Shows the rate of growth of renewable and non-renewable energy resources.  (Source: N. Albokhari).|
With several alternative energy resources coming into consideration, an elasticity of choosing an energy source over the other will become possible in the near future. This diversification phenomenon that is more and more noticed and considered is also a consequence of the remarkably increasing environmental concerns. The environmental movements are aggressively, more than any time before, advocating for pushing toward the reduction of carbon emissions released from traditional fossil fuels resources primarily, coal, natural gas and oil. As we see in Figs. 1 and 2, the rate of growth in renewable energy is greater than that of other energy resources. 
The two main fields which the energy is consumed nowadays are transportation and electricity. Revolutions in automotive efficacy can make electric propulsion economically viable. Furthermore, renewing the electric system to make it diverse, distributed, and renewable can also make it clean, reliable, and secure.  Nonetheless, for transportation, various problems arises when considering the usage of renewable energy. As an example, the energy density, charging issues and the associated costs are impeding factors when utilizing batteries for transportation. On the other hand, the utilization of wind, solar energy in electricity systems is limited. These two sources can be considered only as a variable source of electricity. This is because that wind movement is highly unpredictable and also constrainted geographically as some areas will be exposed to a higher wind than needed and vice versa. Similar problems rises with Solar energy as well. The reduction of the associated intermittency problems requires a lot of investment and infrastructure to mimic the electricity demand profile and smoothen out the output taking into consideration the economics of this process in order to compete with other energy sources. On the other hand, fossil fuels and nuclear energy both have comparative advantage when it comes to generating electricity.
As we mentioned in the introduction, there are many concerns toward the utilization of carbon emitted energy resources. Therefore, with the sustainability advantage of using nuclear energy (a carbon-free resource) in generating electricity, the option to replace traditional coal, oil and natural gas plants seems to be attractive. This comes from the fact that the nuclear energy can perform as a base load power plant with significant capacity that requires little maintenance. By 2008, there were 372 gigawatts (GW) of nuclear-generating capacity, providing roughly 15 percent of the world's electricity. However, nuclear power has been best by problems, starting from safety concerns, to radioactive waste disposal, to the diversion of technologies and fuel for the manufacture of nuclear weapons.  Besides the technical difficulties, the economics can be quite challenging, primarily from the associated capital cost. In the United States, it is estimated that nuclear plants cost twice as much as a coal plant to build and five times what a natural gas plant costs, two competitive sources of energy in power generation. Moreover, the presence of cheap coal and prices of around $55/bbl for oil and below $3/MMSCF for natural gas can be discouraging factor for the utilization of nuclear energy in power systems.
|Fig. 2: World consumption of both renweable and non-renweable energy resourses.  (Courtesy of BP)|
In transportation sector, fossil fuel is superior from both the economical aspects as well as the density energy by weight. When it comes to electricity, oil is not preferred fuel here due to its high cost per BTU produced. Nonetheless, coal and natural gas are two prime fuels used in generating electricity and are excellent in performing as both base and peak load plant, especially in hot days of summer. In addition, technology, accessibility and existing infrastructures favor the fossil fuel plants as compared to nuclear power plants. The idea of the End of Petroleum that is being marketed from the last century is highly inaccurate as we see a rapid technological development in petroleum fields and thus increasing the accessibility to untapped reserves such as the tar oil sands and unconventional natural gas. The current reserve-to-production ratios for both oil and gas are 50.7 and 52.8 years respectively. 
Nonetheless, putting the economics aside, the environmental toll of fossil fuel is high as well the carbon emission cost of fossil fuel when compared to nuclear energy. EU countries carbon price is about 88% below where levels need to be. The OECD said in a report based on an analysis conducted across 41 countries that the emission cost of carbon dioxide needs to increase to at least $34/metric ton. Ninety percent of the world's emissions are taxed -if any- less than $34/metric ton, while 60 percent are not subjected to pricing at all, the OECD said. It is quite questionable if the taxation at this level will be sufficient to hinder the usage of natural gas in electricity - and not only coal - and would give the nuclear energy an economic advantage. If we take Sweeden as an example of one of the leading countries in renewable energy utilization, the carbon tax is reaching there a record high of around $150/metric ton. In all cases, if nations were to raise the charges for pollution at the level of the median nation, the carbon price gap would go down to about 53 percent of the current level. 
Considering the two main sectors of energy consumption, electricity and transportation, fossil fuel is a clear winner in both segments. Factors supporting the usage of fossil fuel resides in economics, safety, convenience including the presence of infrastructure and accessibility. On the other hand, nuclear energy can substitute, at least to an extent, the utilization of fossil fuels in power systems. Regardless of the additional cost, governments and organizations have to consider not only the financial cost but also the environmental cost when choosing an energy resource over the other. Once the technical and the safety aspects are covered, nuclear energy is superior choice when it comes to providing the world with its needs of electricity.
© Nooreddeen Albokhari. 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.
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