Which of the following is not an example of a non-renewable resource?

Question

Which of the following is not an example of a non-renewable resource?

1. A. Coal
2. B. Petroleum
3. C. Groundwater in a recharge-limited aquifer
4. D. Solar energy (Correct answer)

Correct Answer

Option D — Solar energy

Detailed Solution & Explanation

The correct answer is Solar energy.

Key Points

• A non-renewable resource is one whose stock is fixed on a human timescale, so using it depletes it permanently. The question asks which option is not of that kind.
• Solar energy is the standard example of a renewable and effectively inexhaustible flow resource — it arrives continuously and using it today does not reduce tomorrow's supply.
• The other three are non-renewable:
  • Coal and petroleum are fossil fuels formed over hundreds of millions of years.
  • Groundwater in a recharge-limited aquifer is the subtle one: water is normally renewable, but where extraction persistently exceeds recharge the aquifer is being mined, and it behaves as a non-renewable stock.

Additional Information

• The distinction that matters is rate, not category. Any renewable resource harvested faster than it regenerates — groundwater, forests, fisheries, soil — is effectively non-renewable, which is the whole basis of the idea of sustainable yield.
• Renewables are usefully split into flow resources that cannot be stockpiled (solar, wind, tidal) and stock renewables that can be depleted if mismanaged (forests, fish, groundwater).
• India's own case makes the point: parts of Punjab, Haryana and western Uttar Pradesh are classified as over-exploited blocks by the Central Ground Water Board, where the stage of groundwater extraction exceeds 100% of annual recharge.
• Fossil fuels are sometimes called stock resources and renewables flow resources, a framing that makes the depletion logic immediate.