Hi Ramiro,  

I've primarily corrected the first paragraph with suggestions for improvement.  Your writing for the most part makes sense but in some areas is awkward/doesn't sound right.  I know this is not particularly helpful feedback so I also tried to provide suggestions of ways to sound more natural.  Hope this helps.

Kim

IELTS Writing task 2: nuclear power

In the last few years there has been an intense debate about nuclear power and its possible advantages. In this essay I am going to consider *(this isn't wrong but it is passive voice, if you said "I consider" it will be more powerful) the potential benefits and downsides of this type of energy in order to give (again, this isn't super wrong but give doesn't make as much sense.  Maybe instead say you want to add) a reasoned argument to the mentioned debate.
Two main usages of nuclear power must be considered in this essay. The first one regards (awkward use of word regards, m/b say "the first usage is nuclear power as a source of energy") nuclear power as a source of energy. It is an usual (awkward, m/b instead say "It is a commonly asserted fact that...") fact that goverments and energy companies are increasing their usage of nuclear methods, claiming that it is a cheap and clean way to obtain energy to supply the society. I would not deny that it is cheaper than other sources, but I would question whether it is actually cleaner. I seriously doubt about the idea (doubting an idea doesn't make much sense, maybe instead say "I seriously doubt the assertion that nuclear power is an eco-friendly energy source") of nuclear power as an eco-friendly source, since not only are do different specialists claiming the opposite, also there is are also a big large quantity of protests organized by ecologists against nuclear power.
The second usage that we should consider here has to do with the widespread idea of nuclear weapons as a threat that helps to maintain thhe peace between countries. I strongly believe that this idea is wrong. Probably, if nuclear power had not been invented we would not be thinking in about maintaining world peace. In addition, I think that a state of peace that is maintained under a threat is not a real state of peace, but an underlying or undercover state of war. World peace is a goal that must be achieved by democratic dialogues between countries, and not with the threat of a possible war that is about to break out in any moment.
To conclude, nuclear power it is questioned in all its usages and we should provide ourselves,a s a society, with international laws to regulate the possible danger of using it as a source of energy, and to definitely prohibe the creation of nuclear weapong, whi is the real trigger that could awake the armies of the world.