Miscellaneous: UPSC Previous Year Questions (Environment and Ecology)
2 previous year UPSC Prelims questions on Miscellaneous (Environment and Ecology). Choose an option to see the answer and explanation.
Explanations state facts as of the year each question was asked; words like “recently” refer to that year.
Showing 1–2 of 2 questions
UPSC 2024Environment and Ecology · Miscellaneous
Q1. Consider the following materials: 1. Agricultural residues 2. Corn grain 3. Wastewater treatment sludge 4. Wood mill waste Which of the above can be used as feedstock for producing Sustainable Aviation Fuel?
Explanation
Sustainable aviation fuel (SAF), hydrogen and electric all have a role to play in the decarbonization of aviation. SAF is vitally important as it can address decarbonization of fuel over its lifecycle, and this is now available to be used in all turbine engines including in mid and long-range aircraft. Therefore, understanding the feedstock landscape as well as the technology pathways is integral to maximising the production and supply of SAF. The production of SAF starts with one of five main families of raw materials:
Corn grain Oil seeds Algae Other fats, oils, and greases Agricultural residues Forestry residues Wood mill waste Municipal solid waste streams Wet wastes (manures, wastewater treatment sludge) Dedicated energy crops.
Exam tip:
You can try, The "NOT" approach for all statements, this tests the improbability of negating a statement--if denying its impact seems highly unlikely, the statement is plausibly true. For Example: Agri reside or mill waste or sludge are NOT used in fuel manufacturing? unlikely.
UPSC 2024Environment and Ecology · Miscellaneous
Q2. Consider the following: 1. Battery storage 2. Biomass generators 3. Fuel cells 4. Rooftop solar photovoltaic units How many of the above are considered "Distributed Energy Re-sources"?
Explanation
Distributed energy resources, or DERs, are small-scale energy systems that power a nearby location. DERs can be connected to electric grids or isolated, with energy flowing only to specific sites or functions. DERs include both energy generation technologies and energy storage systems. When energy generation occurs through distributed energy re-sources, it is referred to as distributed generation. Examples of distributed energy resources that can be installed include:
Roof top solar photovoltaic units Wind generating units Battery storage Batteries in electric vehicles used to export power back to the grid Combined heat and power units, or tri-generation units that also utilise waste heat to provide cooling Biomass generators, which are fuelled with waste gas or industrial and agricultural by-products. Open and closed cycle gas turbines Reciprocating engines (diesel, oil) Hydro and mini-hydro schemes Fuel cells.
Answer key for these questions
Q
UPSC year
Correct answer
1
2024
(c) 1, 2, 3 and 4
2
2024
(d) All four
Frequently asked questions
How many previous year UPSC questions are there on Miscellaneous?
This page covers 2 previous year UPSC Prelims GS Paper-I questions on Miscellaneous (Environment and Ecology), asked from 2008 to 2025. Each has the correct answer and an explanation.
How should I use previous year UPSC questions for Prelims?
Attempt each question first, then open the answer and read the explanation for every option. Repeat by chapter, and track which statements UPSC reuses across years. Previous year questions show the exam pattern and difficulty level.
Which years are covered for Miscellaneous?
Questions on Miscellaneous (Environment and Ecology) are available for 8 years, from 2008 to 2025. Use the Year filter to practise a single paper.
