September 30, 2015 Energy Written by Greentumble Editorial Team
how nuclear energy works
In its most basic form, nuclear energy is

energy that originates from within the nucleus (core) of an atom. The powerful energy that the atom contains is what holds its dense nucleus together¹. Nuclear energy is used to produce electricity that powers our homes and buildings. An estimated 15% of the world’s electricity comes from nuclear power. Some nations, such as Lithuania, France, and Slovakia obtain nearly all of their electricity from this energy source¹.

The nuclear energy production process

While the production of nuclear energy may sound like a very complicated process, it is produced through the following basic steps:

  1. Nuclear energy production takes place within a nuclear reactor or power plant, where electricity takes place in a controlled environment. Within this reactor, atoms of uranium or some other fuel (such as plutonium) are split through a process called nuclear fission. These split atoms release tiny particles that then cause other atoms of uranium to split in a chain reaction¹. Such chain reactions produce large amounts of heat through kinetic energy².


  1. The heat created through this process warms a cooling agent that produces steam. Water is typically used for this process, but liquid metal or molten salt may be used instead¹.


  1. The steam turns a turbine (or wheels that are turned by a flowing current)¹.


  1. The turbines power generators or engines that produce electricity¹.


The nuclear energy production process is ultimately not that much different from the processes that occur in other types of power plants. The primary difference between different types of power plants is how the heat is generated. In a nuclear plant, fission is used to produce the heat that produces steam, turns the turbines, which then run the electricity generators³. Fossil fuel plants burn coal, oil or natural gas to generate the heat needed to turn the turbines and then generate electricity².

There are two types of nuclear power reactors: Pressurized Water Reactors (PWRs) and Boiling Water Reactors (BWRs):

PWRs keep the cooling water under sufficient pressure where the water is allowed to turn into steam but never to boil. This steam turns the turbine(s) to power the electricity generator. The water from the reactor and the water that is turned into steam are always kept in separate systems³.

BWRs allow the heated water to boil and turn to steam, which turns the turbines and power the electricity generator³.

In both of these types of reactors, the steam is allowed to condense back into water and then it is reused for the same process².

Nuclear fuel

Uranium is the fuel that is most commonly used during the production of nuclear energy. This is because uranium is easy to split apart during the fission process and it can be found in rocks throughout the world. However, U-235, the type of uranium required for the production of nuclear energy, makes up less than one percent of the existing uranium on Earth¹.

The average nuclear reactor will use approximately 59,000 metric tons (65,000 tons) of U-235 uranium each year. Through complex re-enrichment and recycling processes, some uranium and plutonium spent nuclear fuel can be reused, which reduces the need for more mining, extracting, and processing¹.

At the end of the nuclear energy production process, radioactive waste is produced. An object is considered to be radioactive when its atomic nuclei are unstable. Such radioactive materials can be very toxic and result in pollution to the environment and in health problems such as cancers and blood diseases¹. Therefore, radioactive wastes require proper disposal in an environmentally-sound manner.