UPSC CSE Prelims
Question 95
Microbial fuel cells are considered a source of sustainable energy. Why ?
- They use living organisms as catalysts to generate electricity from certain substrates.
- They use a variety of inorganic materials as substrates.
- They can be installed in waste water treatment plants to cleanse water and produce electricity.
Which of the statements given above is/are correct ?
View correct answer and explanation
Correct answer: C
Correct Option: C
Explanation: Microbial fuel cells use electrogenic microorganisms to oxidise organic substrates and transfer electrons to electrodes, potentially treating wastewater while generating electricity.
Statement / Item-wise Analysis:
1: Correct - Correct: microbes act as biological catalysts producing electrical current.
2: Incorrect - Incorrect as a blanket characterisation: conventional microbial fuel cells mainly consume biodegradable organic substrates, not an arbitrary range of inorganic material.
3: Correct - Correct: wastewater systems can combine organic-pollutant degradation with power recovery.
Option-wise Analysis:
A: Incorrect - omits supported item 3.
B: Incorrect - includes unsupported item 2; omits supported item 1.
C: Correct - includes the supported statements and excludes the unsupported ones.
D: Incorrect - includes unsupported item 2.
Review Note: Specialised microbes can oxidise certain inorganic compounds, but the 2011 standard conceptual description centres on organic substrates.