Energy Overview

What is Energy?

• Essential for life and advancement of humans.
• Ability to convert energy from one form to another is crucial.

Types of Energy

• Kinetic Energy: Energy of moving objects, depends on mass and speed.
• Heat Energy: Flows from hot to cold objects, also known as thermal energy.
• Light Energy: Form of electromagnetic radiation, essential for photosynthesis.
• Chemical Energy: Stored in bonds of atoms and molecules, vital for existence.
• Elastic Potential Energy: Stored in stretched or squashed materials.
• Gravitational Potential Energy: Energy due to an object’s height above the ground.
• Electrical Energy: Results from moving electric charges.
• Magnetic Energy: Associated with moving charges, exert forces on other magnetic objects.
• Nuclear Energy: Stored in the nuclei of atoms, can be released through fission or fusion.

Measuring Energy

• Measured in Joules (J), named after James Prescott Joule.
• He demonstrated that different forms of energy can be converted into each other.

Conservation of Energy

• Law of Conservation of Energy: "Energy can neither be created nor destroyed, but only changed from one form to another."
• Devices transfer or convert energy from one form to another, e.g., electric lamp, car engine.
• Waste energy is usually in the form of heat or sound.

Energy Resources

Non-renewable Resources

• Fossil Fuels: Coal, oil, natural gas; formed from remains of dead plants and animals.
  • Advantages: Cheap, reliable.
  • Disadvantages: Non-renewable, polluting, greenhouse gas emissions.
• Nuclear Fuels: Uranium, plutonium; used in nuclear power stations.
  • Advantages: Low greenhouse gas emissions, reliable.
  • Disadvantages: Non-renewable, radioactive waste, high costs.

Renewable Resources

• Wind Energy: Uses kinetic energy of wind.

  • Advantages: Renewable, no fuel costs, low pollution.
  • Disadvantages: Noise, visual impact, wind-dependent.

• Hydropower: Uses kinetic energy of moving water.

  • Advantages: Renewable, no fuel costs, reliable.
  • Disadvantages: Environmental impact, high setup costs.

• Biomass: Organic matter used as energy source.

  • Advantages: Renewable, reduces landfill.
  • Disadvantages: Land use conflicts, CO emissions.

• Geothermal Energy: Heat from underground.

  • Advantages: Renewable, low pollution.
  • Disadvantages: Limited geographic availability.

• Solar Energy: Energy from the sun.

  • Advantages: Renewable, low pollution.
  • Disadvantages: High initial costs, intermittent.

Summary

• Many forms and types of energy exist.
• Energy conservation is a fundamental law.
• Distinction between renewable and non-renewable resources.
• Need for sustainable energy solutions to meet future demands.