Understanding Power Generation: Key Concepts and Principles

Lesson 1

Hydropower Plants: Using the energy generated by the water stored in a swamp to a steep fall on the turbine that mechanically turns the electric generator, which produces electricity.

Nuclear and Thermal Power: Using steam at pressure on the turbines that drive the electric generator. In thermal power, steam is produced by combustion, while in nuclear power, a controlled nuclear reaction with uranium is used as fuel.

Wind Farms: Exploits the kinetic energy of wind for electric power generation by grouping several wind generators.

Photovoltaic Power Plant: It can generate electricity by exploiting the energy from photovoltaic cells that capture sunlight.

Charles Coulomb enunciated what is known as Coulomb's Law to demonstrate experimentally that the value of the force to attract or repel electrically charged particles located at a fixed distance is directly proportional to the product of their charges and inversely proportional to the square of this distance.

Electric Field: It is the region of space where the forces of attraction or repulsion of electric charges are exhibited.

Potential Difference: The work required to move a unit charge between two points in an electric field. U_AB = E · d

Voltage Supply: Energy provided by a generator to promote an electric charge of 1 coulomb between two points in the circuit; the voltage is measured in volts (V).

Frequency: The number of times per second that a wave of alternating current voltage or signal occurs. The unit is hertz (Hz).

Electric Intensity: The amount of electric charge flowing through a material or substance in one second.

i = AQ / AT =

Current Density: The relationship between the amount of electric current passing through a geometric body and its cross-sectional area. j = i / S

Resistivity: The characteristic resistance presented by a conductor with a 1 mm² cross-section and 1 meter length at a given temperature.

Temperature Coefficient: This parameter indicates the increase or decrease in resistivity due to temperature changes.

Conductance: Expresses the degree of ease with which a material allows electric current to flow. G = 1 / R

Ohm's Law: The current through a metallic conductor is proportional to the voltage across its ends; the constant of proportionality between voltage and current is the resistance of the conductor. U = I · R

Joule's Law: The work done or heat energy generated in a circuit is proportional to the resistance multiplied by the square of the current and the time that the current flows. T = i² · R · t

Circuit Elements: Electric generator, receiving or electric charges, electric conductors, switching elements, and safety and protection elements.

Found in a simple circuit: fuse (protective device), switch (control), bulb (receiver of electric charge), cable (electrical conductor).

Receivers or Electric Charges:

• Light Receptors: Convert electrical energy into light, e.g., incandescent bulbs.
• Thermal Receptors: Convert electrical energy into thermal energy, e.g., electric stoves.
• Mechanical Receptors: Transform electrical energy into mechanical energy, e.g., AC and DC motors.
• Electrochemical Receptors: Convert electrical energy into chemical energy, e.g., rechargeable batteries.

Safety Elements and Protection:

• Overcurrent or Overload: Abnormally high currents caused by excessive consumption of connected loads.
• Short Circuit: A direct connection of the two poles of a generator circuit, usually occurring by accident or carelessness.
• Surge: Caused by a malfunction of the generator, providing a voltage greater than the nominal value.
• Fuse: A simple protective device designed to prevent overcurrent and short circuits.
• Breaker: More sophisticated protective devices than fuses.

Switches: Safety devices that prevent adverse effects on individuals' health when leakage currents are possible.