What is nuclear energy made from?

Answer 1

In general, nuclear energy comes from the energy associated with atomic nuclei. There is nuclear fusion, which happens in stars and in fusion weapons, and there is nuclear fission. Nuclear fusion is the "combining" of lighter atomic nuclei to create heavier ones, and many fusion reactions release energy. (Again, think of stars.) In contrast, nuclear fission is the "splitting" of atomic nuclei to release energy. The latter is technology that we've come to use fairly widely, and we have developed fission nuclear weapons and the nuclear reactor to tap nuclear energy via fission. Let's look at the latter device, the reactor.

The fission of nuclear fuel (also known as atomic fuel, such as uranium or plutonium) is where we get nuclear energy. And what happens during nuclear fission is that the nuclei of fuel atoms absorb neutrons and fission (split), releasing lots of energy. In fission, that larger atomic nucleus breaks into a pair of smaller ones, and these fission fragments recoil with a lot of kinetic energy. The fuel traps the fission fragments, and the energy they came away with is converted into thermal energy in the fuel.

We derive nuclear energy by tapping the energy of formation of atomic nuclei via fusion or fission. This is advanced technology that is less than a century old. We're still working to use it well and wisely.