Compared with 2007–08, which of the following primary energy sources recorded…
2013
Compared with 2007–08, which of the following primary energy sources recorded the highest growth in production in 2008–09?
Answer: A. Coal & lignite — ConceptYear-on-year production growth compares the same source across two consecutive years. The percentage-growth formula is: ((current-year production −…
- A.
Coal & lignite
- B.
Crude petroleum
- C.
Natural gas
- D.
Hydro & nuclear electricity
Attempted by 2 students.
Show answer & explanation
Correct answer: A
Concept
Year-on-year production growth compares the same source across two consecutive years. The percentage-growth formula is: ((current-year production − previous-year production) / previous-year production) × 100.
When all sources are expressed in the same energy unit, their percentage changes can be compared directly.
Application
Coal & lignite: ((8,476 − 7,926) / 7,926) × 100 ≈ 6.9%.
Crude petroleum: ((1,403 − 1,429) / 1,429) × 100 ≈ −1.8%.
Natural gas: ((1,265 − 1,248) / 1,248) × 100 ≈ 1.4%.
Hydro & nuclear electricity: ((5,133 − 4,944) / 4,944) × 100 ≈ 3.8%.
Cross-check
Source | 2007–08 (PJ) | 2008–09 (PJ) | Growth |
|---|---|---|---|
Coal & lignite | 7,926 | 8,476 | ≈ 6.9% |
Crude petroleum | 1,429 | 1,403 | ≈ −1.8% |
Natural gas | 1,248 | 1,265 | ≈ 1.4% |
Hydro & nuclear electricity | 4,944 | 5,133 | ≈ 3.8% |
The largest of the four year-on-year changes is approximately 6.9%. Therefore, coal & lignite recorded the highest production growth in 2008–09.