Previous Year Question
Assertion (A): Deserts can be potential source for generating sustainable energy.
Reason (R): Deserts receive more energy from the Sun in six hours than mankind consumes in a year.
Select the correct answer from the codes given below:
Both (A) and (R) are true and (R) is the correct explanation of (A).
Both (A) and (R) are true, but (R) is not the correct explanation of (A).
(A) is true, but (R) is false.
(A) is false, but (R) is true.
Correct Answer: A
Detailed Solution
Assertion (A) is correct. Deserts are important potential sources of Sustainable Energy Generation through Solar Energy. Desert regions generally experience limited cloud cover, intense Solar Radiation, and extensive open land, which increases the possibility of establishing large-scale solar power plants. Solar Energy is a Renewable Energy Source that can help reduce dependence on fossil fuels and carbon emissions associated with energy production.
Reason (R) is also correct. According to a historical estimate associated with the DESERTEC concept, the world's deserts receive more solar energy in just six hours than humanity consumes in an entire year. This idea was popularized by the German physicist Gerhard Knies. According to estimates by the German Aerospace Center (DLR), the Sahara Desert receives approximately 2,200–2,800 kilowatt-hours of solar energy per square metre annually. This demonstrates the enormous solar energy potential of desert regions. However, the six-hour estimate refers to incoming solar radiation rather than the immediate conversion of all that energy into usable electricity.
Solar Energy can be utilized in deserts mainly through two technologies. In Solar Photovoltaic (PV) Systems, solar cells convert sunlight directly into electrical energy. The second technology is Concentrated Solar Power (CSP), in which mirrors concentrate sunlight at a particular point or region to generate heat, which is subsequently used to operate turbines and produce electricity. CSP plants equipped with Thermal Energy Storage can continue generating electricity for some time after sunset.
The DESERTEC project concept was developed to utilize the enormous solar energy potential of desert regions in North Africa and the Middle East for renewable electricity generation. However, challenges such as dust accumulation, extreme temperatures, limited water availability, energy storage, and long-distance electricity transmission must also be addressed.