Fission Energy with Thorium
Thorium can be used for nuclear energy.
If thorium had been selected instead then there would have been no nuclear meltdowns because thorium reactors are self limiting and can’t run away. The energy released in nuclear fission generates heat which is then used to generate steam to drive a turbine and generator.
Traditionally large atoms like uranium or plutonium are split into other smaller atoms, releasing energy in the process, and this has been going on for over sixty years. See Fission Energy for more details. However, a large section of the public cannot be persuaded about the benefits of fission energy, for two key reasons.
Nuclear fission reactions can, and do, get out of control, as shown by Three Mile Island, Chernobyl, and more recently Fukushima.
Nuclear fission powerplants also produce copious amounts of highly radioactive nuclear waste, some of which will remain hazardous for tens of thousands of years, creating significant disposal or safe storage problems. Safe storage is easily achieved but public opinion has yet to be convinced.
Nuclear Electricity
Making electricity from neutrons, the basis of nuclear fission power, has now been understood for around seventy years. The neutron flux causes more than enough heating, in a blanket of surrounding material, typically cooled with water to generate the steam needed to drive turbine generators. In conventional nuclear fission powerplants, the hot fluid transfers its heat to generate superheated steam. Feeding the steam into a turbine drives a generator which produces the electricity to feed the grid. All along the way, in a rather tortuous scheme, there are numerous significant efficiency losses. So, you need to generate enormous amounts of energy to compensate and this is what nuclear fission can easily do.
So is Nuclear Power Green?
Yes and no. In operation they produce little if any CO2 but the construction of these very large power plants does involve a huge amount of energy and generates a lot of CO2 due to the massive amounts of concrete and steel necessary.
Why use Uranium and Plutonium for Nuclear Power?
The choice of uranium and plutonium for nuclear power generation instead of thorium was simple – you can easily make nuclear weapons with uranium and plutonium, but not easily with thorium.