Nuclear Fission was the process of splitting an atom. Fission Power was using nuclear fission to create electricity. It was very controversial.
Fission Power was a result of the Manhattan Project which worked to invent the atomic bomb during World War II. Four scientists in the US, including Jewish physicist Albert Einstein, were concerned about Nazi Germany developing the atomic bomb first, so they sent a letter to President Roosevelt. As a result, the Manhattan Project was created. The first bomb they created was made of Uranium-235 and dropped on Hiroshima. The second bomb was made of plutonium and dropped on Nagasaki. This ended World War II. After the Manhattan Project disbanded in 1947, more nuclear weapon tests occurred. Other countries acquired nuclear weapons. The first hydrogen bomb was created in 1951 in the US. At the same time, scientists turned to using nuclear power for electricity.
Tech Level: 9-11
The earliest reactors were prototypes that were tested in the 1950s. Nuclear fission reactors were commercialized in 1960s. They did not become controversial until 1979 when Three Mile Island went to nuclear hell. The reactor there melted down. As investigations went on, another nuclear meltdown occurred in Chernobyl which exploded in 1986 causing massive radiation poisoning in Russia. In the 1990s, more advanced so-called Generation III reactors came into service. These were improved versions of the conventional Generation II reactors as they came to be called. However, the controversy did not subside until the 2030s.
Generation IV nuclear fission reactors were new, more advanced reactors. They solved all the problems of conventional reactors. They were pebble bed reactors which used small balls instead of fuel rods which provided advantages over conventional reactors. A nuclear meltdown was impossible. The uranium was only 9% enriched. Not even Iran could use it to create nuclear weapons. The nuclear waste was easier to dispose of. Finally, these new, more advanced reactors were cheaper than fossil fuels. Nuclear fission power was now a lucrative industry. But there was a problem. Uranium was a limited resource. Using thorium to make uranium was only a temporary solution. By the mid-21st century, fission was replaced with fusion.