Question

Microbial fuel cells are considered a source of sustainable energy. Why?

1. They use living organisms as catalysts to generate electricity from certain substances.

2. They use a variety of inorganic materials as substrates.

3. They can be installed in wastewater treatment plants to cleanse water and produce electricity.

Which of the statements given above is/are correct?

1. 1 only
2. 2 and 3 only
3. 1 and 3 only
4. 1, 2 and 3

Answer 1

Correct Answer - Option 3 : 1 and 3 only

The correct answer is 1 and 3 only.

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• Microbial fuel cells :
  • A microbial fuel cell is a device that converts chemical energy to electrical energy by the action of microorganisms. Hence, statement 1 is correct.
  • They are devices that use bacteria as catalysts to oxidize organic and inorganic matter and generate current. Hence, statement 2 is not correct.
  • A research paper from the Massachusetts Institute of Technology earlier this year explained that electrons produced by the bacteria are transferred to the negative terminal and flow to the positive terminal. 
  • In a statement on the ZSL website, Conservation Technology Specialist Al Davies explained: “Plants naturally deposit biomatter as they grow, which in turn feeds the natural bacteria present in the soil, creating energy that can be harnessed by fuel cells and used to power a wide range of vital conservation tools remotely, including sensors, monitoring platforms and camera traps.”
  • Among conventional power sources, batteries must be replaced while solar panels rely on a source of sunlight. On the other hand, plants can survive in the shade, naturally moving into position to maximize the potential of absorbing sunlight.
  • They can be installed in wastewater treatment plants to cleanse water and produce electricity. Hence, statement 3 is correct.

• At the London Zoo, a fern has started taking its own selfies, the Zoological Society of London (ZSL) announced.
• ZSL scientists had laid the groundwork for the feat earlier this year, with the ultimate aim of using plants to power camera traps and sensors in the wild.
• This they achieved by installing microbial fuel cells in Pete, a maidenhair fern.