UPSC Prelims Practice Questions — Energy from space
Q1. In the context of space-based solar power, the term 'rectenna' refers to which one of the following?
- A. An orbiting reflector that concentrates sunlight solely onto photovoltaic panels aboard the satellite
- B. A ground-based antenna array that receives the beamed microwave energy and converts it into DC electricity
- C. The onboard device that converts collected solar electricity exclusively into a high-energy laser beam
- D. A geostationary relay station that redirects microwaves only between two satellites
Q2. The method of wirelessly transmitting solar energy collected in space to Earth by microwaves, using a large satellite antenna and a ground rectenna, was first described/patented by whom?
- A. Peter Glaser
- B. Gerard K. O'Neill
- C. Freeman Dyson
- D. Konstantin Tsiolkovsky
Q3. Shimizu Corporation's proposed 'Luna Ring' envisages a continuous 11,000 km solar-cell belt running along which single feature of the Moon?
- A. The lunar equator
- B. The rim of the South Pole–Aitken basin
- C. The boundary between the near side and the far side
- D. A great circle passing through both lunar poles
Q4. The 'Luna Ring' concept for generating solar power on the Moon and beaming it to Earth has been put forward by which one of the following?
- A. Shimizu Corporation, a Japanese construction and engineering firm
- B. The Japan Aerospace Exploration Agency (JAXA)
- C. Mitsubishi Heavy Industries
- D. Japan Space Systems
Q5. With reference to the origins and early development of the space-based solar power concept, consider the following statements:
1. The idea of transmitting power by microwaves from a satellite to a ground rectenna was first described by Peter Glaser in 1968.
2. The 1979 NASA/DOE reference system envisaged a 5-GW baseload plant in geostationary orbit.
3. The US programme was effectively discontinued around 1980 owing to its very high projected cost.
4. The 1970s reference study was led by the European Space Agency's SOLARIS programme.
Which of the statements given above is/are NOT correct?
- The idea of transmitting power by microwaves from a satellite to a ground rectenna was first described by Peter Glaser in 1968.
- The 1979 NASA/DOE reference system envisaged a 5-GW baseload plant in geostationary orbit.
- The US programme was effectively discontinued around 1980 owing to its very high projected cost.
- The 1970s reference study was led by the European Space Agency's SOLARIS programme.
- A. 4 only
- B. 1 and 4
- C. 2 and 3
- D. 3 and 4
Q6. With reference to NASA's Office of Technology, Policy and Strategy (OTPS) cost-benefit study on space-based solar power, consider the following statements:
1. It analysed two geostationary-orbit architectures each designed to deliver about 2 GW of power to Earth.
2. Its lower-cost architecture produced electricity at roughly $0.61 per kWh, still more than ten times the cost of terrestrial renewables.
3. It concluded that the lifecycle greenhouse-gas emissions of space-based solar power would be far higher than those of terrestrial alternatives.
Which of the statements given above is/are correct?
- It analysed two geostationary-orbit architectures each designed to deliver about 2 GW of power to Earth.
- Its lower-cost architecture produced electricity at roughly $0.61 per kWh, still more than ten times the cost of terrestrial renewables.
- It concluded that the lifecycle greenhouse-gas emissions of space-based solar power would be far higher than those of terrestrial alternatives.
- A. 1 and 2 only
- B. 1 and 3 only
- C. 2 and 3 only
- D. 1, 2 and 3
Q7. As examined in NASA's OTPS report, 'space-based solar power' is best defined as which one of the following?
- A. Collecting solar energy on satellites in space and wirelessly transmitting it to Earth (chiefly by microwaves) for conversion into grid electricity
- B. Using orbiting mirrors to reflect extra sunlight onto existing ground-based solar farms at night
- C. Generating electricity from the solar wind captured by charged tethers in Earth's magnetosphere
- D. Storing surplus terrestrial solar electricity in batteries aboard satellites for later use
Q8. As per official figures, what was India's cumulative installed solar power capacity as on 31 March 2026 — the terrestrial benchmark against which space-based solar economics are judged?
- A. About 150 GW
- B. About 62 GW
- C. About 129 GW
- D. About 283 GW
Q9. With reference to the drawbacks of space-based solar power compared with terrestrial renewables, consider the following statements:
1. It involves a very high capital cost of launching thousands of tonnes of hardware into orbit or to the Moon.
2. The satellite array is vulnerable to disabling collisions with space debris.
3. Its lifecycle cost per unit of electricity is many times higher than that of terrestrial renewables.
4. Unlike terrestrial solar, it cannot generate power during cloud cover or at night.
Which of the statements given above is/are NOT correct?
- It involves a very high capital cost of launching thousands of tonnes of hardware into orbit or to the Moon.
- The satellite array is vulnerable to disabling collisions with space debris.
- Its lifecycle cost per unit of electricity is many times higher than that of terrestrial renewables.
- Unlike terrestrial solar, it cannot generate power during cloud cover or at night.
- A. 4 only
- B. 3 only
- C. 2 and 4
- D. 1 and 3
Q10. Under Japan's JAXA-linked OHISAMA project, the 2025 demonstration aimed to wirelessly transmit solar power from a low-Earth-orbit satellite of approximately what mass?
- A. About 180 kg
- B. About 18 kg
- C. About 1,800 kg
- D. About 500 kg