Model Answer
0 min readIntroduction
Solar energy, a renewable and sustainable resource, is gaining prominence in India’s energy mix. Two primary technologies harness this energy: Concentrated Solar Power (CSP) and Photovoltaic (PV) solar energy. While both convert sunlight into usable energy, they employ distinct methods. PV technology directly converts sunlight into electricity, while CSP uses mirrors to concentrate sunlight to generate heat, which then drives a turbine to produce electricity. Understanding the nuances of each technology is vital for informed energy policy and investment decisions.
Concentrated Solar Power (CSP)
CSP technologies utilize mirrors or lenses to concentrate a large area of sunlight onto a receiver. The concentrated heat is then used to generate steam, which drives a turbine connected to a generator, producing electricity. There are several types of CSP:
- Parabolic Trough: Uses curved, trough-shaped mirrors.
- Solar Power Tower: Employs a central receiver atop a tower surrounded by mirrors (heliostats).
- Dish/Engine Systems: Uses parabolic dish mirrors focusing sunlight onto a receiver connected to a Stirling engine.
CSP offers the advantage of thermal energy storage, allowing for electricity generation even when the sun isn't shining. However, it requires direct sunlight and significant water resources for cooling.
Photovoltaic (PV) Solar Energy
PV technology directly converts sunlight into electricity using semiconductor materials. When photons from sunlight strike the semiconductor, they excite electrons, creating an electric current. PV systems can be deployed in various scales, from small rooftop installations to large-scale solar farms.
- Crystalline Silicon: The most common type, offering good efficiency and durability.
- Thin-Film Solar Cells: Made from materials like cadmium telluride (CdTe) or copper indium gallium selenide (CIGS), offering lower costs but generally lower efficiency.
PV systems are modular, scalable, and require less water than CSP. However, they lack inherent storage capabilities and their efficiency is affected by temperature and shading.
Comparative Analysis
| Feature | Concentrated Solar Power (CSP) | Photovoltaic (PV) |
|---|---|---|
| Working Principle | Concentrates sunlight to generate heat, then electricity. | Directly converts sunlight into electricity. |
| Efficiency | Typically 15-25% (overall system efficiency). | Typically 15-22% (commercial modules, can be higher in labs). |
| Cost | Higher initial cost, but potential for lower levelized cost with storage. | Decreasing costs, becoming increasingly competitive. |
| Land Use | Requires more land per MW due to mirror field. | Requires less land per MW. |
| Storage | Easily integrated with thermal energy storage. | Requires separate battery storage systems. |
| Water Usage | High water consumption for cooling. | Low water consumption. |
India’s Solar Energy Landscape
India has ambitious solar energy targets under the National Solar Mission (2010). As of November 2023, the installed solar capacity is over 73 GW, with PV dominating the landscape. While CSP projects have been initiated, their deployment remains limited due to cost and water availability concerns. The government is promoting both technologies through various policies and incentives, including Production Linked Incentive (PLI) schemes for solar PV manufacturing.
Conclusion
Both CSP and PV technologies play crucial roles in transitioning towards a sustainable energy future. While PV currently dominates due to its cost-effectiveness and scalability, CSP offers unique advantages with its inherent storage capabilities. A diversified approach, leveraging the strengths of both technologies, is essential for ensuring energy security and achieving India’s ambitious renewable energy goals. Further research and development are needed to improve the efficiency and reduce the cost of both technologies.
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.