Prelims 2014 · archive
EasyWith 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?
Answer & explanation
Answer: (a) 1 only
Only statement 1 is correct. Photovoltaic cells turn sunlight straight into electricity, while solar thermal plants first make heat and then use it to run a turbine. The AC/DC claim in statement 2 is reversed. India already had a photovoltaic manufacturing base in 2014, so statement 3 is wrong.
- ✓ 1. Photovoltaic cells convert sunlight directly into electricity. Solar thermal plants use the Sun's heat to warm a heat-transfer fluid, which produces steam to drive a turbine and generator.
- ✗ 2. Photovoltaic cells produce direct current (DC), and an inverter is needed to convert it to AC for the grid. Solar thermal plants generate electricity through a turbine-driven generator, which gives AC. The statement has the two the wrong way round.
- ✗ 3. India was already manufacturing photovoltaic modules by 2014. A Ministry of New and Renewable Energy release puts India's installed solar PV module manufacturing capacity at 2.3 GW in 2014. The statement's claim of no PV manufacturing base is false.
Remember · PV = light to DC electricity directly, with an inverter needed for AC. Solar thermal = heat, then steam, then turbine, then AC. India had PV module manufacturing capacity by 2014.
📘 Read it in NCERT: Class 10 Contemporary India – II, Ch 5 (practise this chapter)
Sources
- NCERT Class 10 · Contemporary India – II, Chapter 5 “Photovoltaic technology converts sunlight directly into electricity. Solar energy is fast becoming popular in rural and remote areas.”
- U.S. Energy Information Administration: Solar thermal power plants ↗ “a heat-transfer fluid is heated and circulated in the receiver and used to produce steam. The steam is converted into mechanical energy in a turbine, which powers a generator to produce electricity.”
- U.S. Energy Information Administration: Photovoltaics and electricity ↗ “PV cells generate direct current (DC) electricity. DC electricity can be used to charge batteries that power devices that use DC electricity.”
- PIB, Ministry of New and Renewable Energy press release on solar manufacturing ↗ “Since 2014, India's installed solar PV module manufacturing capacity has grown from 2.3 GW to approximately 67 GW, thanks to various measures under the "Make in India" initiative.”
Question: UPSC Civil Services (Preliminary) 2014, General Studies paper. Explanation: Minimalist IAS, checked 25 Oct 2026 (how we verify). ·