Can you store nuclear energy

Answer 1

Nuclear energy is already stored as binding energy in the atom nuclei and is released either by nuclear fission, by nuclear fusion, or radioactive decay of these nuclei.

So, I think the question could be:

Can we store nuclear power?

or
Can we store the power (electrical, mechanical, or thermal power) released from nuclear fission or nuclear fusion? .

The answer is: yes, we can store the power produced from nuclear fission or nuclear fusion.

For example, thermal power produced from nuclear fission in nuclear power plants can be used to produce hydrogen by thermochemical water decomposition (at efficiencies higher than 90 %). This hydrogen could be used later either in fuel cells to produce electricity during peak electric demand periods or could be used in transportation to fuel internal combustion engines.

Another example is to use the electricity produced in nuclear power plants, during off-peak electricity demand periods, to pump water from a lower reservoir to a high reservoir and then during peak electricity demand periods this water is allowed to fall down on turbines connected to electricity generator system and thus producing electricity.