Nuclear energy is considered a moderately dangerous energy source. It cannot be seen, but that doesn't mean that it is clean. However, it produces no harmful greenhouse gases. Nuclear energy is an expensive source of energy. It is not easily accessible nor affordable for many people.
Nuclear energy produces radioactive waste, which is harmful to the environment. So, we can say that nuclear energy is both good and bad. Some features make it more interesting, but some make it dangerous. It depends on the usage and purpose of an individual.