Hey, good job! I have round 2 of suggestions below. But we are down to "refinements" instead of "corrections" already.
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"Potential energy -
It is the energy that an object has due to its position in a gravitational field."
A clarification before the statement may be helpful. "While there are other forms of potential energy, but in the context of electric generation we will typically be referring to Potential Energy in a gravitational field..."
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"Kinetic energy
It is the energy that an object has due to its speed of movement."
The words "speed of movement" could be replaced with just "motion". A statement such as "It is the energy of an object due to its motion. The faster the motion, the more the energy. Mathematically, the kinetic energy is proportional to "the Square of the Velocity".
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"Thermal energy
... ...
This is the most degraded form of energy and it is the most difficult to transform, especially if it is at low temperatures."
This statement bugs me since "degraded form" is not well defined. Bugs me, but I think I understand what you are saying. It may be adequate but can easily lead to wrong interpretation. You can eliminate that statement without affect the content of that paragraph. An alternate way to saying what I think you want to express may be: "Typically, wasted energy eventually dissipate as heat without performing useful work."
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"Chemical energy
....
To release this energy it is necessary to cause chemical reactions, which in most cases consist of burning fuels with oxygen."
While using the word "burning" can be technically correct, but "burning" suggest fire and flame to most audience. There is no flame they can see when their ATP molecules are oxidized. Thus, I suggest replacing "...burning fuels with oxygen..." with "...the fuel reacts with oxygen releasing energy in the process..."
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"Electric energy
...A disadvantage of electrical energy is that it cannot be easily stored, it must be consumed at the moment it is created. In order to store electrical energy, it is necessary to convert it into chemical energy in batteries or into mechanical energy in pumped hydroelectric plants."
Your statement is entirely correct. But from prior paragraphs, your target audience is not likely to know what is "pumped hydro storage". You may expand that with an added line "Pumped Hydro is essentially excess energy from solar or wind farms are used to pump water back above a dam to store, and when needed re-convert it back to electrical energy like any other dam"
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Speaking of dams, I am thinking you may want to point this out as well:
There are risks with dams too, regular dam -- pump or no pump. Earthquake due to a dam is not unusual. After all, you are adding a lot of weight to that little area behind the dam.
Take a look at this article and decide for yourself if you want to add a word or two about that.
https://archive.internationalrivers.org/earthquakes-triggered-by-damsWindmill kills birds, solar farm has its own drawback, nature doesn't give us anything for free I suppose.
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Hey, good job there! We can refine till kingdom comes, but even if you don't include any of these round 2 improvements, there isn't much one can complain about.