Chapter 5: Minerals and Energy Resources

1. Introduction

Minerals and energy resources form the backbone of modern civilization. They are the natural endowments that facilitate industrial growth, technological advancement, and infrastructure development. Minerals are extracted from rocks, while energy resources include fossil fuels, hydropower, and renewable sources. These resources power industries, transportation, and households, making them indispensable for economic progress. However, over-exploitation and environmental degradation have raised concerns about their sustainability. In light of this, efficient utilization and conservation of these resources are crucial. The chapter delves into the significance, classification, and distribution of minerals and energy resources, as well as the measures for their conservation.

2. What is a Mineral?

A mineral is a naturally occurring inorganic substance with a specific chemical composition and a crystalline structure. Minerals are formed through various geological processes over millions of years and are the building blocks of rocks. They are categorized based on their physical and chemical properties, such as hardness, luster, and color. Minerals can be metallic, non-metallic, or energy resources like coal. The study of minerals is called mineralogy.

3. Rocks

Definition: Rocks are solid masses of minerals or mineral-like substances. They form the Earth’s crust and come in various sizes, shapes, and textures.

Formation: Rocks are formed through various geological processes such as cooling of molten magma, sedimentation, or heat and pressure. These processes result in the formation of different types of rocks.

Types of Rocks:

• Igneous Rocks: Formed by the cooling and solidification of magma or lava (e.g., granite, basalt).
• Sedimentary Rocks: Formed by the deposition and compaction of sediments (e.g., sandstone, limestone).
• Metamorphic Rocks: Formed when existing rocks undergo changes due to extreme heat and pressure (e.g., marble, slate).

4. Classification of Minerals

Minerals are broadly classified into:

• Metallic Minerals: These contain metals and are typically hard and shiny. Examples include iron ore, bauxite, and copper.
  • Ferrous Minerals: Contain iron (e.g., iron ore, manganese).
  • Non-Ferrous Minerals: Do not contain iron but may contain other metals (e.g., gold, silver, copper).
• Non-Metallic Minerals: These minerals do not contain metals. Examples include limestone, mica, and gypsum.
• Energy Minerals: These minerals provide energy and include coal, petroleum, and natural gas.

5. Mode of Occurrence of Minerals

Minerals occur in various forms, depending on the geological processes involved in their formation:

• In Veins and Lodes: Metallic minerals like gold, silver, and copper are found in veins and lodes formed by the cooling and solidification of magma.
• In Beds or Layers: Non-metallic minerals like coal and sedimentary deposits like iron ore are found in horizontal layers formed over millions of years.
• As Alluvial Deposits: Minerals such as gold, platinum, and tin are found in alluvial deposits of sands and gravels.
• In Ocean Waters: Magnesium and bromine are extracted from seawater. Some mineral deposits also occur in the ocean floor.

6. Conservation of Minerals

Minerals are non-renewable resources, meaning they cannot be replenished once exhausted. As industrial demand increases, it becomes essential to conserve these resources. Some key measures for the conservation of minerals include:

• Efficient Utilization: Using minerals judiciously and minimizing waste during extraction and processing.
• Recycling: Recycling metals like aluminum and copper can significantly reduce the pressure on mining activities.
• Substitution: Using alternative materials in place of scarce minerals can help conserve resources. For example, plastic and composite materials are often used in place of metals.

• Legislation: Governments enforce strict laws to regulate mining activities and reduce environmental impacts.
• Sustainable Mining: Encouraging eco-friendly mining practices that cause minimal environmental disruption.

7. Energy Resources

Definition: Energy resources are the natural resources used to produce energy that powers industries, homes, and transportation.

Types of Energy Resources:

1. Conventional Energy Resources: These include fossil fuels like coal, petroleum, and natural gas, as well as hydropower. They are non-renewable and finite.
2. Non-Conventional Energy Resources: These include renewable sources such as solar, wind, geothermal, tidal, and biomass energy. They are sustainable and environmentally friendly.

Classification and Uses:

• Fossil Fuels: (Coal, Petroleum, Natural Gas) Used for electricity generation, transportation, and industrial production.
• Hydropower: Generated from moving water, used for electricity.
• Solar Energy: Utilizes sunlight, used in solar panels for electricity.
• Wind Energy: Harnesses wind power through turbines, used for electricity generation.
• Geothermal Energy: Uses Earth’s internal heat, applied in electricity generation and heating.
• Bioenergy: Renewable energy produced from organic matter like biomass and biogas.
• Nuclear Energy: Energy released from nuclear fission of atoms in a controlled chain reaction.

Regions:

• Coal: Found in Jharkhand, Odisha, Chhattisgarh, West Bengal.
• Petroleum: Found in Gujarat, Assam, Mumbai High, Krishna-Godavari Basin.
• Solar and Wind Energy: Prominent in Rajasthan, Gujarat, Tamil Nadu.

8. How does energy generated using energy resources

Energy generation using different energy resources, especially in electricity production, generally involves converting a natural source of energy (like wind, water, steam, or sunlight) into mechanical energy, which then drives a turbine. The turbine, in turn, converts this mechanical energy into electrical energy using a generator. Below is an overview of how energy is produced using various resources and how turbines function in this process.

1. Energy Generation Using Fossil Fuels (Coal, Natural Gas, Petroleum)

In power plants that use fossil fuels (coal, natural gas, or petroleum), the process follows these steps:

• Combustion: The fossil fuel is burned in a furnace to produce heat.
• Boiling Water: The heat from combustion is used to boil water, creating high-pressure steam.
• Turbine Operation: The high-pressure steam is directed at the blades of a turbine, causing it to spin.
• Generator: The spinning turbine drives a generator, which converts the mechanical energy into electrical energy.
• Working of the Turbine: In this case, the steam pushes the blades of the turbine, making them rotate. The turbine’s shaft is connected to the generator. As the shaft spins, the generator converts the mechanical rotation into electricity by moving magnets past a coil of wire, creating an electric current.

2. Hydropower (Hydroelectric Energy)

In hydroelectric power plants, energy is harnessed from moving water, usually from a dam the procedure is as follows:

• Water Release: Water stored in a dam is released, flowing with great force down through a penstock (a channel or pipeline).
• Turbine Operation: The force of the water flow hits the turbine blades, making the turbine spin.
• Generator: The turbine is connected to a generator, and the mechanical motion is converted into electrical energy.
• Working of the Turbine: In hydropower systems, the kinetic energy of flowing water is used to rotate the turbine blades. The greater the flow and height (head) of the water, the more efficiently the turbine spins, driving the generator.

 3.Wind Energy

In wind turbines, the mechanical energy is derived directly from wind power:

• Wind Capture: Large blades of the wind turbine catch the wind, causing the blades to rotate.
• Turbine Operation: The rotating blades turn a rotor connected to a turbine.
• Generator: The rotor is connected to a generator, which converts the rotational mechanical energy into electrical energy.
• Working of the Turbine: Wind energy turns the large blades, which rotate around a central hub. The spinning hub turns a shaft connected to a generator. The motion of the shaft within the generator induces an electric current, converting the mechanical energy from the wind into electricity.

4. Solar Power (Concentrated Solar Power or CSP)

While solar photovoltaic panels convert sunlight directly into electricity, Concentrated Solar Power (CSP) systems can use a turbine:

• Sunlight Concentration: Mirrors or lenses are used to concentrate sunlight onto a receiver, heating a fluid (like molten salt).
• Heat Transfer: The heated fluid is used to produce steam.
• Turbine Operation: The steam drives a turbine.
• Generator: The turbine is connected to a generator, converting mechanical energy into electricity.
• Working of the Turbine: CSP systems follow the same principle as fossil fuel plants. Instead of burning fuel to create steam, concentrated sunlight heats the fluid to generate steam, which drives the turbine.

5. Geothermal Energy

In geothermal power plants, heat from the Earth’s interior is used:

• Hot Water/Steam Extraction: Hot water or steam is extracted from deep underground reservoirs.
• Turbine Operation: The steam is directed at the turbine blades, causing them to spin.
• Generator: The spinning turbine is connected to a generator, which converts the mechanical energy into electricity.
• Working of the Turbine: Similar to fossil fuel and CSP plants, the geothermal steam drives the turbine’s blades, spinning the shaft of the turbine and generating electricity.

6. Tidal Energy

In tidal power plants, energy is derived from the rise and fall of ocean tides:

• Water Movement: As tides rise and fall, they cause water to flow in and out of reservoirs.
• Turbine Operation: The moving water turns turbines, much like hydropower.
• Generator: The turbine is connected to a generator, converting the mechanical energy of the water flow into electrical energy.
• Working of the Turbine: The motion of water due to tides is used to rotate the turbine blades, driving the generator in a similar manner to hydroelectric turbines.

General Working of a Turbine in Energy Generation

• Turbine Structure : A turbine typically has a set of blades mounted on a rotor, which is connected to a shaft. When an energy source (wind, steam, water) causes the blades to spin, the rotor turns the shaft.
• Conversion to Electricity: The turbine’s shaft is connected to a generator. Inside the generator, the shaft rotates a magnet within a coil of wire, inducing an electric current. This process is called electromagnetic induction.
• Efficiency Factors: The efficiency of a turbine depends on factors such as the speed of the moving medium (water, wind, steam), the turbine blade design, and the generator’s ability to convert mechanical energy into electricity.

In summary, the key function of a turbine in energy generation is to convert mechanical energy (from moving air, water, or steam) into rotational energy, which is then converted into electrical energy by a generator. Each type of energy resource—whether fossil fuels, water, wind, or steam—uses a turbine to facilitate this conversion process.

9. Conservation of Energy Resources

Energy resources, especially non-renewable ones, need to be conserved to ensure sustainability. Measures include:

• Efficient Energy Use: Adopting energy-saving appliances and practices in industries and households.
• Promotion of Renewable Energy: Encouraging the use of solar, wind, and hydropower to reduce dependence on fossil fuels.
• Legislative Measures: Governments can impose regulations to limit overconsumption and promote cleaner energy.
• Research and Innovation: Investing in research to improve energy efficiency and discover new renewable energy sources.