Model Answer
0 min readIntroduction
Renewable energy sources are gaining prominence globally as concerns over climate change and fossil fuel depletion intensify. Defined as energy derived from natural processes that are replenished at a higher rate than they are consumed, these sources offer a sustainable alternative to conventional energy. As of 2023, renewables accounted for approximately 30% of global electricity generation. India, committed to achieving 500 GW of non-fossil fuel energy capacity by 2030 under the Panchamrita commitment at COP26, is rapidly expanding its renewable energy portfolio. This answer will detail the mainstream forms of renewable energy, their technologies, and their role in India’s energy landscape.
Solar Energy
Solar energy harnesses the sun’s radiation for electricity generation. Two primary technologies are employed:
- Photovoltaic (PV) cells: Convert sunlight directly into electricity using semiconductor materials. These are used in solar panels for residential, commercial, and utility-scale applications.
- Concentrated Solar Power (CSP): Uses mirrors to concentrate sunlight to heat a fluid, which then drives a turbine to generate electricity.
Advantages: Abundant resource, low maintenance, scalable. Disadvantages: Intermittency (dependent on sunlight), land use requirements, initial cost. India’s National Solar Mission (2010) aims to promote solar power development.
Wind Energy
Wind energy utilizes wind turbines to convert kinetic energy into electricity. Turbines are typically grouped into wind farms, often located in coastal areas or hilly regions with consistent wind speeds.
Advantages: Clean energy source, relatively low operating costs. Disadvantages: Intermittency (dependent on wind), noise pollution, potential impact on bird populations. India has a significant wind energy potential, particularly in states like Tamil Nadu, Gujarat, and Maharashtra.
Hydroelectric Energy
Hydroelectric power is generated by harnessing the energy of flowing water. This is typically achieved through dams that create reservoirs, allowing for controlled water release to drive turbines.
Advantages: Reliable energy source, provides water storage and flood control. Disadvantages: Environmental impact (dam construction alters river ecosystems), displacement of communities, potential for sedimentation. India has a substantial installed hydroelectric capacity, with projects like the Tehri Dam being prominent examples.
Biomass Energy
Biomass energy involves utilizing organic matter – such as agricultural residues, forestry waste, and animal dung – for energy production. This can be achieved through:
- Direct combustion: Burning biomass to generate heat for cooking or electricity.
- Biogas production: Anaerobic digestion of biomass to produce methane-rich biogas.
- Biofuels: Converting biomass into liquid fuels like ethanol and biodiesel.
Advantages: Renewable resource, reduces waste, supports rural economies. Disadvantages: Potential for air pollution (if not burned efficiently), land use competition. The New National Policy on Biofuels (2018) promotes the production and use of biofuels in India.
Geothermal Energy
Geothermal energy taps into the Earth’s internal heat for electricity generation or direct heating applications. This involves drilling wells to access hot water or steam reservoirs.
Advantages: Consistent energy source, low greenhouse gas emissions. Disadvantages: Limited geographical availability, potential for induced seismicity, high initial costs. Geothermal energy potential in India is concentrated in regions like the Puga Valley in Ladakh and the Cambay basin.
| Energy Source | Technology | Advantages | Disadvantages | India's Status |
|---|---|---|---|---|
| Solar | PV Cells, CSP | Abundant, Low Maintenance | Intermittency, Land Use | ~65 GW installed capacity (as of Nov 2023) |
| Wind | Wind Turbines | Clean, Low Operating Costs | Intermittency, Noise | ~42 GW installed capacity (as of Nov 2023) |
| Hydro | Dams, Turbines | Reliable, Water Storage | Environmental Impact, Displacement | ~46 GW installed capacity (as of Nov 2023) |
| Biomass | Combustion, Biogas, Biofuels | Renewable, Waste Reduction | Air Pollution, Land Use | ~11 GW installed capacity (as of Nov 2023) |
| Geothermal | Wells, Heat Exchange | Consistent, Low Emissions | Limited Availability, Cost | Limited development, potential in specific regions |
Conclusion
Mainstream renewable energy sources offer a viable pathway towards a sustainable energy future. While each source has its own advantages and disadvantages, their combined potential is significant. India’s ambitious renewable energy targets require continued investment in technology, infrastructure, and policy support. Addressing intermittency challenges through energy storage solutions and grid modernization will be crucial for maximizing the contribution of renewables to the nation’s energy mix. A diversified approach, leveraging the strengths of each renewable energy source, is essential for achieving energy security and environmental sustainability.
Answer Length
This is a comprehensive model answer for learning purposes and may exceed the word limit. In the exam, always adhere to the prescribed word count.