Passage

Directions for the following 5 (five ) items : Read the following two passages and answer the items that follow each passage. Your answers to these items should be based on the passages only. Passage-1 Biomass as fuel for power, heat, and transport has the highest mitigation potential of all renewable sources. It comes from agriculture and forest residues as well as from energy crops. The biggest challenge in using biomass residues is a long-term reliable supply delivered to the power plant at reasonable costs; the key problems are logistical constraints and the costs of fuel collection. Energy crops, if not managed properly, compete with food production and may have undesirable impacts on food prices. Biomass production is also sensitive to the physical impacts of a changing climate. Projections of the future role of biomass are probably overestimated, given the limits to the sustainable biomass supply, unless breakthrough technologies substantially increase productivity. Climate-energy models project that biomass use could increase nearly four-fold to around 150 – 200 exajoules, almost a quarter of world primary energy in 2050. However the maximum sustainable technical potential of biomass resources (both residues and energy crops) without disruption of food and forest resources ranges from 80 – 170 exajoules a year by 2050, and only part of this is realistically and economically feasible. In addition, some climate models rely on biomass-based carbon capture and storage, an unproven technology, to achieve negative emissions and to buy some time during the first half of the century. Some liquid biofuels such as corn-based ethanol, mainly for transport, may aggravate rather than ameliorate carbon emissions on a life-cycle basis. Second generation biofuels, based on ligno-cellulosic feedstocks – such as straw, bagasse, grass and wood – hold the promise of sustainable production that is high-yielding and emit low levels of greenhouse gases, but these are still in the R & D stage.

Which of the following can lead to food security problem ? 1. Using agricultural and forest residues as feedstock for power generation 2. Using biomass for carbon capture and storage 3. Promoting the cultivation of energy crops Select the correct answer using the code given below :

(a) 1 and 2 only
(b) 3 only ✓ UPSC's answer
(c) 2 and 3 only
(d) 1, 2 and 3

Why the answer is (b)

• The passage explicitly states that 'Energy crops, if not managed properly, compete with food production and may have undesirable impacts on food prices,' directly linking the cultivation of energy crops to food security issues.

• Regarding agricultural and forest residues, the passage identifies the main challenges as 'logistical constraints and the costs of fuel collection,' not competition with food production.

• Biomass-based carbon capture and storage is described as an 'unproven technology' used to achieve negative emissions, but the text does not associate it with disrupting food supply or prices.

• Therefore, only statement 3 is supported by the passage as a cause of food security problems, making option (b) the correct answer.

Why the other options are wrong

(a) 1 and 2 only: Statement 1 is incorrect because the passage attributes challenges with residues to logistics and cost, not food competition, and statement 2 is not linked to food security in the text.
(c) 2 and 3 only: Statement 2 is incorrect because the passage does not state that biomass-based carbon capture and storage leads to food security problems.
(d) 1, 2 and 3: Statements 1 and 2 are incorrect because the passage does not identify the use of residues or carbon capture technologies as causes of food security issues.

Asked in the CSAT Paper II of the UPSC Civil Services Preliminary Examination 2016, held on 7 August 2016. Question and answer key: Union Public Service Commission. Explanation: UPSC Answer Check.