With reference to 'Direct Air Capture', an emerging technology, which of the following statements is/are correct? I. It can be used as a way of carbon sequestration. II. It can be a valuable approach for plastic production and in food processing. III. In aviation, it can be a source of carbon for combining with hydrogen to create synthetic low-carbon fuel. Select the correct answer using the code given below.
- (a) I and II only
- (b) III only
- (c) I, II and III ✓ UPSC's answer
- (d) None of the above statements is correct
Why the answer is (c)
• Direct Air Capture (DAC) uses fans and chemical sorbents to pull carbon dioxide straight out of ambient air, unlike point-source capture at a chimney.
• Statement I is correct: the captured CO2 can be injected into deep geological formations for permanent storage — carbon sequestration (as at Climeworks' Orca and Mammoth plants in Iceland).
• Statement II is correct: captured CO2 can be used as a feedstock for polymers and plastics and in food processing, e.g. carbonating drinks and greenhouse enrichment.
• Statement III is correct: combining DAC-derived CO2 with green hydrogen yields synthetic 'e-fuels' or sustainable aviation fuel that are low-carbon over their life cycle.
• Hence I, II and III, option (c).
Why the other options are wrong
- (a) I and II only
- Statement III on synthetic aviation fuel is also correct.
- (b) III only
- Statements I and II are also correct.
- (d) None of the above statements is correct
- All three describe genuine DAC applications.
Asked in the GS Paper I of the UPSC Civil Services Preliminary Examination 2025, held on 25 May 2025. Question and answer key: Union Public Service Commission. Explanation: UPSC Answer Check.