Sources of Energy

Electromagnetic Induction

the process of generating electricity by moving a magnet near a coil of wire or moving the wire near a magnet.

Electric Generator

a device that converts mechanical energy into electrical energy. It works based on the principle of electromagnetic induction discovered by Michael Faraday.

Renewable Energy Sources

resources that are naturally replenished and can be used repeatedly. They produce little to no greenhouse gas emissions and help combat climate change and reduce air pollution.

Examples of Renewable Energy Sources

geothermal, hydroelectric, wind power, solar cells, and biomass.

Geothermal Energy

energy that utilizes heat from the Earth’s crust. The heat produces underground steam that powers turbines to generate electricity.

Hydroelectric Energy

energy that harnesses the kinetic energy of moving water. Water flowing through dams turns turbines connected to generators to produce electricity.

Wind Power

energy that converts mechanical energy from wind into electricity through wind turbines.

Solar Cells

photovoltaic cells that convert light energy from the sun into electricity.

Biomass

organic matter from plants, animals, and microorganisms used as an energy source.

Non-Renewable Energy Sources

resources that cannot be regained once used and take a long time to replenish. They have a finite supply and often contribute to pollution and climate change.

Key Characteristics of Non-Renewables

finite supply, pollution, higher greenhouse gas emissions, and easy storage and transportation.

Examples of Non-Renewable Energy Sources

fossil fuels and nuclear energy.

Fossil Fuels

hydrocarbons derived from the organic remains of prehistoric organisms, such as coal, oil, and natural gas.

Coal

a fossil fuel used for electricity generation and steel production. Its disadvantages include high CO₂ emissions and mining damage.

Oil (Petroleum)

a fossil fuel used for transportation fuel, plastics, and heating. Its disadvantages include air pollution and oil spills.

Natural Gas

a fossil fuel used for heating, cooking, and electricity. Its disadvantage is methane emissions, which are a potent greenhouse gas.

Combustion of Fossil Fuels

a process where hydrocarbons react with oxygen to produce carbon dioxide, water, and energy.

General Reaction of Hydrocarbon Combustion

Hydrocarbon + Oxygen → Carbon dioxide + Water.

Methane Combustion

CH₄ + 2O₂ → CO₂ + 2H₂O + Energy.

Nuclear Energy

energy released from the nucleus or core of an atom.

Electrochemical Batteries

devices that produce electricity through electrochemical reactions.

Parts of a Battery

anode, cathode, and electrolyte.

Primary Batteries

disposable batteries that cannot be recharged. Examples include alkaline, mercury, silver-oxide, and zinc carbon batteries.

Secondary Batteries

rechargeable batteries. Examples include lead-acid and lithium batteries.

Geothermal Energy in the Philippines

primarily used to generate electricity. It is derived from heat energy in the Earth’s crust and produces steam that powers turbines.

Advantages of Geothermal Energy

less harmful to the environment compared to fossil fuels.

Disadvantages of Geothermal Energy

produces carbon dioxide, nitrous oxide, and sulfur dioxide. Water disposal can also be an issue because it contains salt.

Hydroelectric Power

uses moving water to turn turbines in power plants. It is a major source of electricity in Mindanao.

Hydropower Principle

water stored in reservoirs becomes potential energy. When released, it becomes kinetic energy that turns turbines connected to generators.

Factors Affecting Hydroelectric Electricity Production

volume of water flow and hydraulic head.

Hydraulic Head

the distance between the water’s surface and the turbines.

Wind Turbines

devices strategically placed to capture mechanical energy from wind and convert it into electricity.

Solar Energy

energy from the sun converted into electricity through photovoltaic cells or solar thermal technology.

Photovoltaic Cells

cells that convert light energy into electricity using semiconductor materials, usually silicon.

Advantages of Solar Energy

plentiful, low-maintenance, and environmentally friendly compared to fossil fuels.

Disadvantages of Solar Energy

expensive, requires rare metals, takes up large spaces, and produces some emissions during manufacturing.

Solar Thermal Technology

a process where mirrors or reflectors concentrate sunlight to heat liquid, produce steam, and spin turbines connected to generators.

Biomass Energy

energy from organic matter such as plants, animals, microorganisms, crop remains, manure, and garbage.

Biogas or Biofuels

fuels produced through microorganisms breaking down organic matter in a multi-step process.

Sustainable Energy Source

an energy source that can be continuously replenished, such as biomass when trees are replaced after being cut.