T1

• Energy can be classified into several types based on different criteria:

  • Primary and Secondary energy
  • Commercial and Non-commercial energy
  • Renewable and Non-Renewable energy
  • Conventional and Non-conventional energy
• Primary energy sources are found or stored in nature, such as coal, oil, natural gas, and biomass
• Primary energy sources are converted into secondary energy sources, like coal, oil, or gas converted into steam and electricity
• Commercial energy sources available in the market for a price are electricity, coal, and refined petroleum products
• Non-commercial energy sources not available in the market for a price include firewood, cattle dung, and agricultural wastes
• Renewable energy sources are continuously and freely produced in nature and not exhaustible, such as solar, wind, micro hydro, biomass, ocean thermal, and tidal energy
• Renewable energy is captured from existing flows of energy from natural processes like sunshine, wind, flowing water, biological processes, and geothermal heat flows
• Non-renewable energy sources like coal, oil, and gas are likely to deplete with time and require external action to initiate the supply of energy
• Conventional energy resources include gasoline, kerosene, coal, natural gas, and nuclear energy
• Non-conventional energy systems use renewable resources, are small-scale, decentralized, and easily sized to meet energy demand, such as biogas plants, wind pumps, solar home systems, solar battery charging stations, and micro hydro power plants
• Advantages and disadvantages of different energy resources like fossil fuels, nuclear, solar, water, wind, geothermal, and biomass
• Solar energy uses photovoltaic cells to collect the sun's energy and generate electricity
• Wind energy is caused by the uneven heating of the atmosphere and can be converted into electricity using wind turbines
• Hydro power harnesses the energy of falling water by converting gravitational potential energy into kinetic energy through a generator
• Geothermal energy relies on heat produced under the Earth's surface and is not dependent on the Sun
• Biomass can be converted into fuels through processes like solid fuel combustion, digestion, pyrolysis, fermentation, and catalyzed reactions
• Ocean energy sources include wave movement, tides, ocean currents, and ocean thermal energy
• Ocean Thermal Energy Conversion (OTEC) produces electricity using the temperature difference between deep cold ocean water and warm tropical surface waters