First of all, it is important to understand what renewable energy means. Basically, any resource that can replenish itself within a given period can be considered renewable. For example, the most commonly used renewable energy sources are wind, solar energy, biomass, and geothermal processes. In this case, this means that people can harness power through these sources because they are, in a way, always there.
Uranium, one of the fuels used in fission nuclear power reactors, is not a renewable source if we limit it to the uranium on Earth. However, nuclear energy could become renewable if we begin using seawater. It has been found that there is an infinite amount of uranium in seawater. Uranium regenerates from a steady chemical reaction between the water and the rocks that contain the mineral. This reaction happens quickly enough that whatever is pulled from the water is leached from the rocks to replace it. According to different experts' opinions, humans can't extract enough uranium to lower the overall seawater concentrations faster than replenished. Even though the uranium present in seawater is in smaller units than found on Earth, it is estimated that there are about 4.5 billion tons of uranium present in seawater at any given time. This amount of uranium would sustain the production of nuclear energy for years.
Studies are being conducted in Japan, China, and the United States that are finding ways to extract uranium from the ocean water. These studies are finding ways to pull the uranium from the seawater in a clean and possibly renewable way.
But using breeder reactors (nuclear reactor able to generate more fissile material than it consumes), it is possible to fuel the Earth with nuclear energy indefinitely. Although the amount of uranium deposit available could only supply nuclear energy for about 1000 years, Professor Cohen at the University of Pittsburg believes the actual amount of uranium deposit available is way more than what is considered extractable right now. In his arguments, he includes uranium that could be extracted at a higher cost, uranium from the seawater, and uranium from eroding earth crust by river water. If used in a breeder reactor, all of those possible uranium resources would be enough to fuel the Earth for another 5 billion years and hence renders nuclear energy renewable energy.
If the fusion process could be controlled in the future, then fusion nuclear power reactors could indefinitely generate the fuel it needs to produce energy.
Based on what has been said above, nuclear energy can be considered a renewable energy source.
Experts have always debated whether nuclear energy should be considered a renewable or non-renewable energy resource. I am among those who agree with what Jorge has explained. Thank you, Jorge!
Dear all, Jorge Morales Pedraza explained it almost perfectly. Almost, because (naturally) his answer is written from a human perspective. From universe's point of view, I cannot find anything to be infinite. Together with Salah-Eddine Bentridi I would thus say that harnessing power from nuclear reactions is not renewable, but certainly sustainable.
Similar distinction was used in the fabulous book Sustainable energy - Without the hot air, written by David J.C. MacKay (highly recommended; available for free at http://withouthotair.com/).
Do excuse me for being a philosophical hairsplitter. : )
Yes, the energy that is produced by nuclear power plants is renewable, but the fuel that is required is not renewable. Although uranium is a very common metal found all over the world, nuclear fission requires uranium known as U-235, which is comparatively rare.
I have a different idea about nuclear use for fission and fusion.
The nuclear issue must always be viewed with great care, since it can always be used as a weapon, especially nuclear fission.
I think we will need all sources of energy for many decades. And it doesn't matter if it is renewable or not. Especially because it is a fact that renewable energy sources, although important, are not enough for human needs.
I believe that with efforts of scientific community and the construction of the Tokamak ITER (www.iter.org) to start operations in 2025, we have a path to first nuclear fusion reactor and this must be an event that will mark humanity.
Initially your reaction will depend on two compounds, tritium and deuterium. With the knowledge and greater availability of energy it will be possible to move on to next step and move to a nuclear fusion reactor with only deuterium reactions.
This will allow humanity to reach a new level of prosperity as electric energy will be very abundant given very efficient process of nuclear reaction to fusion.
I very much hope that my descendants can accomplish more with this greater availability of energy.
Nuclear energy is usually considered another non-renewable energy source. Although nuclear energy itself is a renewable energy source, the material used in nuclear power plants is not.
When I read the question posed by Dr Muhammad Abid Saeed, although I could see that this would be correct, I looked at the link above, sent by Oluwadara Pelumi Omotayo and really enjoyed reading it. The section 'Other Non-renewable Energy Sources; Nuclear Energy'
explains this in just the right amount of detail for me! Now, I do understand!