Identify the correct sequence of energy sources in order of their share in the…
2011
Identify the correct sequence of energy sources in order of their share in the power sector in India :
Answer: B. Thermal > hydro > nuclear > wind — ConceptThe share of an energy source in a power sector is that source's portion of the sector's total, expressed as a percentage. It can be measured on two…
- A.
Thermal > nuclear > hydro > wind
- B.
Thermal > hydro > nuclear > wind
- C.
Hydro > nuclear > thermal > wind
- D.
Nuclear > hydro > wind > thermal
Show answer & explanation
Correct answer: B
Concept
The share of an energy source in a power sector is that source's portion of the sector's total, expressed as a percentage. It can be measured on two different bases — installed capacity, meaning the generating capacity that is in place, or electricity generated, meaning the energy actually produced over a year — and the two bases need not produce the same ranking.
To arrange sources "in order of their share", compute each source’s percentage on the intended basis and then sort those percentages from largest to smallest.
Application
For India the basis intended here is electricity generated, and the utility-generation figures for the period this question belongs to (Central Electricity Authority and MOSPI data, financial year 2010-11) are as follows.
Source | Electricity generated (FY 2010-11) | Share of total |
|---|---|---|
Thermal (coal, lignite, gas, diesel) | ≈ 665 BU | ≈ 78.7% |
Hydro | ≈ 114 BU | ≈ 13.5% |
Nuclear | ≈ 26 BU | ≈ 3.1% |
Wind | ≈ 19–23 BU | ≈ 2.2–2.8% |
Here BU means billion units, that is, billion kilowatt-hours.
Sorting these shares from the largest downwards gives Thermal > Hydro > Nuclear > Wind.
Cross-check
Thermal has to come first: coal-based generation on its own exceeds every other source put together, so any sequence that opens with hydro or with nuclear contradicts the basic structure of India’s grid.
Hydro sits second: at roughly 13 to 14 percent of generation it is more than four times the nuclear share, so a sequence that places nuclear above hydro reverses a large and well-documented gap.
Nuclear stands just ahead of wind: about 3.1 percent against wind’s 2.2 to 2.8 percent, a narrow but consistent margin in the generation data of that period.
The basis matters. On installed capacity instead (thermal about 65 percent, hydro about 22 percent, wind about 8 percent, nuclear about 3 percent) wind would come ahead of nuclear and give Thermal > Hydro > Wind > Nuclear, a sequence that is not offered among the choices. That absence is the signal that the comparison is intended on the electricity-generated basis.
Answer
Hence the required sequence of energy sources by their share in India’s power sector is Thermal > Hydro > Nuclear > Wind.