With reference to technologies for solar power production, consider the following statements : 1. 'Photovoltaics' is a technology that generates electricity by direct conversion of light into electricity, while 'Solar Thermal' is a technology that utilizes the Sun's rays to generate heat which is further used in electricity generation process. 2. Photovoltaics generates Alternating Current (AC), while Solar Thermal generates Direct Current (DC). 3. India has manufacturing base for Solar Thermal technology, but not for Photovoltaics. Which of the statements given above is/are correct?
- (a) 1 only ✓ UPSC's answer
- (b) 2 and 3 only
- (c) 1, 2 and 3
- (d) None
Why the answer is (a)
• Statement 1 is correct: photovoltaic cells convert sunlight directly into electricity, while solar thermal (CSP) concentrates sunlight to heat a fluid that drives a turbine.
• Statement 2 is wrong: photovoltaics produce direct current (converted to AC by inverters); solar thermal plants use conventional turbine-generators that produce AC.
• Statement 3 is wrong: India has a photovoltaic manufacturing base (cells and modules) but little solar-thermal manufacturing.
• Hence 1 only, option (a).
Why the other options are wrong
- (b) 2 and 3 only
- Statements 2 and 3 are both wrong.
- (c) 1, 2 and 3
- Statements 2 and 3 are wrong.
- (d) None
- Statement 1 is correct.
Asked in the GS Paper I of the UPSC Civil Services Preliminary Examination 2014, held on 24 August 2014. Question and answer key: Union Public Service Commission. Explanation: UPSC Answer Check.