What is Energy? 💡
In our fast paced society, we often hear the growing demand for energy to power our transportation, commercial and residential sectors 🏠. However, many individuals do not fully understand the concept of energy and the impact processing has on our environment.
The concept of energy is complex as there are many forms that it takes place in and can be transformed. Therefore it is essential to be able to identify the two main categories of energy - Kinetic and Potential.
Important to know- Potential energy can be converted into kinetic energy.
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Kinetic energy refers to energy in moving objects.
1. Radiant Energy ⇨ Light moves in waves
Example: Solar panels capture the light from the sun ☀️
2. Thermal Energy ⇨ Heat is what causes movement of atoms or molecules
Example: Biomass thermal energy captures energy from sources derived from the sun. As seen by the combustion of wood, the process of photosynthesis requires the sun.
3. Mechanical Energy ⇨ Movement of substances
Example: Windmills convert the kinetic energy from the wind into mechanical energy through the rotation of its blade.
4. Sound Energy ⇨ Movement in waves
Example: Alarm going off transmits sound waves
5. Electrical Energy ⇨ Movement of electrons
Example: The Electrical power grid transmits electrical energy to consumers.
Potential energy refers to energy that is stored.
1. Chemical Energy ⇨ Stores within bonds that hold molecules together
Example: Incomplete combustion of methane CH4 releases energy.
2. Nuclear Energy ⇨ Stored Within a nuclei of atom
Example: Nuclear power plants generate electricity through atom fission
3. Elastic Energy ⇨ Stored in an object by applying force
Example: Stretching a rubber band
4. Gravitational Energy ⇨ Stored by position
Example: A ball positioned at top of building
Units of Energy
Energy can be measured through a joule, calorie, a British thermal unit (BTU) or a kilowatt. Power is measured through a watt or horsepower.
Basic unit of energy → Joule (J)
1 gigajoule (GJ) = 1 Billion joules = 10^9 J
1 exajoule (EJ) = 1 Billion GJ = 10^18 J
1 Quad (only in US) = 1 quadrillion (1015) BTU (British thermal units) = 1.055 EJ