My objective of study.
When I was a child, I used to disassemble many  of my toys
to see  how their inner workings were
. I believe this was the  sign I would be interested in engineering later in my life.  I believe
an engineer must be able to understand how simple things are interconnected, and how they create a complex and coordinated whole, and how it works.  For example, how parts, nuts, gears, come to life turning a still toy or machine into clockwork.
I am in my  third year of electrical engineering undergraduation at  Mogi das Cruzes University.
So far, the time I spent there provided me with solid knowledge on my  field of study
. However, I believe that studying in an American university will be an excellent opportunity to
expand my learning.
I do not intend to take the same courses I am taking
on my regular graduation
in Brazil for two reasons:
First, I want to have/take advantage of
a richer academic curriculum, making the most of the knowledge available
during my time as an undergraduate student.
Second,  I intend to know the latest on alternative/renewable energy resources and software security, two areas which Brazil is to catch up with the States, Europe and other developed countries.
 That will be an area in which all the world will have to concentrate massive efforts. And adress the issue of how we consume energy and fuel, along with the depleting of non-renewable resources , wich could change the world in ways that we all have not are prepared to. Since, lack of energy or decreasing its generation, would lead to world recession, cut on creatures comforts, and decline in a scale unheard of.
Due to its location and territorial size, Brazil annually receives (generates?/consumes?/or both...) 1013 MWh in solar energy (monthly?/yearly?), which corresponds to  about 50 thousand times its annual consumption. Therefore
, I am most eager to study photovoltaic cells, since it has such enormous potential to provide us a lot of clean energy.
Despite Brazil’s solar energy potential, we still rely on hydropower to generate 80% of our electricity. Home solar power systems  are not very popular yet. Mostly because of their high initial cost, due to taxes and fabrication costs.
While government can reduce taxes on this kind of product, the latter can solved with making of less expensive panels and more efficient solar cells. (I changed quite a bit here, but for clarity and shortening)
Software security is a big world concern as well, not only in industry but also in regular citizen’s homes. Unfortunately, my academic program only covers the basics of it. As I believe the United States is one-step ahead of most countries regarding this area, I am hoping to take courses that involve network security and cryptography.
Finally, I understand that besides researchers, entrepreneurs also have a crucial part in the development of technology and society in general, for they bring innovational ideas to this world. Therefore, I want to seize this  opportunity to develop an entrepreneur mind, by taking a course that shows how to apply my creativity to/in
the business world.
 This can be a gamble of yours, the thing is, the examiner(s) can think you are not original, just think how many guys would say that they did that?
Or they could think that you are commited, since you are into it since tender age. But then, when you choose a traditional approach you will have to show extra creativity/imaginative plan of attack. Take in account that they have seen it all.
 Perhaps you may cut the “of my”. Certainly you wouldn´t dissassemble someone´s else toys.
 Just for vocabulary variety and also a natural way of saying it as well.
 “...or was the sign”, I like it more assertive, reading before one would ask “how many signs would be needed” to know that the career is for you? Would that sign, among others, be the main one? or would be other(s) perhaps more important?
 Beginning with “after all” in English sounds odd to me, I would expect that at the end, or at the middle of a paragraph.
 Try examplify things, or elaborate, as much as you can. Don´t leave a vague statement.
 Using shortening, slangs, overly informal language, is not advisable. Thus, I changed “3rd” to “third”. I left out the “currently”. If you are, then you are currently.
 Just an aside notice, just stating that you are an undergraduate student at the university, perhaps would do. Many may (or may not) think you are a braggart.
But I really don´t know if the CsF (SWF) examiners let this pass or not. So, I left that bit untouched. It´s not a competition between about institutions, but a student´s writing skills test.
 I like “field of study” best. But then, it´s me.
[10/11] Beware of enumerations. First/second beginning the paragraph there would be/is better. The way it was sounds like having more ideas than punctuations. It could leave the reader confused.
 With:“I intend to fill a gap in the traditional electric engineering approach of most Brazilian universities, which is the lack of alternative/renewable energy resources and software security teaching. I believe those fields are very important for an up-to-date electrical engineer.”
You are being categorical (even though you are a layman) and positive, you have a decisive diagnosis, in essays we avoid ''I know it wall/it cover all'' approaches. There are shades of grey in-between.
Plus, you stated that “you” intend to fill the gap, a bit pretentious (dramatical, I mean) of you, ain´t it?
 As for the bit:For if the non-renewable resources of the world ends and we are not prepared for it, our society will certainly face a huge collapse, since energy is something the human race will always need in order to live and to progress.
You had to specify it more, elaborate more. With “how/why/where/who”, giving examples or illustrating it, making the imagery more vivid. The reader has to know what you are talking about, your sense of purpose, your directness. He/she have to convinced, to know that you know your stuff, that you made your homework, read about it, researched, interviewed, you whatever it took, then you wrote about it. You have to be convincing/persuasive.
 and  Isn´t there a contradiction? Looks like Brazil “receives” much more than its annual consumption. If I didn´t misinterpreted, of course.
 Home solar power systems, I would use, instead of “ Home solar energy converters”. Nothing wrong with this, but the other is a more natural way.
 are not very popular yet = did not catch on yet. But in this case you also could keep your writing as it is. This is just another way to say that.
When it comes to writing, it´s good to know other ways to say the same thing. It´s a good exercise to build English vocabulary.
 You don´t normally seize occasions but opportunities.
It´s advisable to get into the habit of providing a title, it´s a bit like making a title of a movie. That is, it would be preferably, one that sums up briefly "the story" of the piece of text. It would be, in a way, the conclusion of the conclusion.
All in all, your writing was good for a first, you just needed to polish it a bit more.
My revised dradt will need some proofread/editing as well. It was just another point of view, done by a human, and as such it may have some mistakes as well.
So, corrections and comments are welcome.
Plus, don´t be afraid of mistakes and corrections, I acquainted (sort of) with "redação" in Portuguese, I was put through
the process sometimes, usually my teachers "nitpicked" my works, I felt like Portuguese was Greek for me. Then, when I went to those exams I passed all of them.
You know, teachers and revisers have to point out some flaws, but they don´t mean you any harm, they mean you good!
Hope it helps.