Fossil energy is taking a good 85% of the the energy mix worldwide as of now. I doubt this will change despite all the beautiful discourses and considering how fossil energy is also used to make solar panels and wind turbines. The thing is that we already reached the peak of oil production and many small economical inconveniences like economical and social crises are partly due to them.
Unfortunately, nuclear energy has been boycotted in the past and there has seen nearly 0 improvement since the 70's. That's mainly due because of propaganda, lobbying, political pressures... For instance, one of the major concern about nuclear fission is pretty much like plane: It's safer and kill less than coal (or car), but the incidents are very sensational and newspapers will sure not miss the chance to make big titles about it.
Moreover, you need a lot of money to build a plant or develop the technology, and a lot of time. As you may have seen it already, most of our politicians are shortsighted and will almost never invest in long term projects. For them, as long as nuclear energy is cheap as it is now, then there is no reason to invest in developing new technoogy to optimize it. It first needs to become expensive so that they eventually start to cogitate about making a move to suggest the idea of... well, you understood the nightmare it can be. The lack of move has considerably slowed down the evolution of nuclear energy (fission, not fusion here) for many reasons; among which I find lobbying in favour of a very new unreliable "renewable" energy and against nuclear (instead of developping both) was unacceptable and pretty much a reason for money laundering and greenwashing.
Now, mentionning nuclear fusion, this is still a very experimental technology from my understanding. It has faced many challenges as well, including scientific and technical challenges. As it is, more or less, "creating a mini Sun" in your garage, the difficulty to handle very high temperatures is very hard, not even talking about the energy consumption you need first.
Similarly to nuclear fission, it also needs time and quite a few dolaritos of investments. Almost nothing, just like decades and dozens of billions dolars, for something some people also believe to be as dangerous as fission.
That is a lot information and is MUCHHH more than what we hear in school bc we always here that you need a lot of energy like with sun panels and windmachines (so it is clean energy). BUTTT in my country you can get a lot of energy with that only it is not possible now to put it on the electric system because it is FULL!! I have no idea if i say that correctly in English but it means that new energy cant go on the electric system and if you want for example a shop or a house or a factory you first need to know if you can be on the system or you have NOOO energy. So in our country that is maybe more important than where you get energy bc if you cant put it on that system you cant use it. Sorry if i make a mess in translating this in English but i have no idea how to translate it differently.
And i have a question: if you have nuclear energy it can maybe also be super dangerous because ONE mistake and a lot of people can die right? And our country is not super big so maybe a LOTTT of people can be victim if there is a mistake or a terror attack. Or is that not true anymore? ππ Thank you very much if you can tell about that because that would be for me a super worry if in my country which is super small there are MORE nuclear factories.