Energy & Environment — UPSC Prelims Previous Year Questions
52 questions from UPSC CSE Prelims GS Paper 1 on Energy & Environment (Science & Technology). Spanning from 1995 to 2025. Practice with show/hide answers and detailed explanations.
Based on 52 questions across 27 years, UPSC has consistently tested aspirants' understanding of Energy & Environment within the broader Science & Technology syllabus. The questions range from factual recall to application-based analysis.
Recent trends show UPSC moving towards statement-based questions that combine multiple aspects of Energy & Environment. Aspirants should focus on understanding concepts rather than memorizing isolated facts.
Q: 'प्रयास वात प्रसारण (कार्बन एयर कैप्चर)', जो नई उभरती प्रौद्योगिकी है, के संदर्भ में, निम्नलिखित कथनों में से कौन-सा/कौन-से सही है/हैं?
I. इसे कार्बन पृथक्करण की एक विधि के रूप में प्रयोग में लाया जा सकता है।
II. यह प्लास्टिक उत्पादन हेतु और खाद्य प्रसंस्करण में एक महत्वपूर्ण उपयोग हो सकता है।
III. विमानन ईंधन, या संश्लेषित न्यून-कार्बन ईंधन जन्म देने हेतु, इससे प्राप्त CO₂ को हाइड्रोजन के साथ संयोजन किया जा सकता है।
नीचे दिए गए कूट का प्रयोग कर सही उत्तर चुनिए:
Q: निम्नलिखित प्रकार के वाहनों पर विचार कीजिए :
I. पूर्ण बैटरी विद्युत् वाहन
II. हाइड्रोजन ईंधन सेल वाहन
III. ईंधन सेल-विद्युत् हाइब्रिड वाहन
उपर्युक्त में से कितने वैकल्पिक पॉवरट्रेन वाहन माने जाते हैं?
Q: विद्युत् वाहन बैटरियों के संदर्भ में, निम्नलिखित तत्वों पर विचार कीजिए :
I. कोबाल्ट
II. ग्रेफाइट
III. लिथियम
IV. निकल
उपर्युक्त में से कितने सामान्यतः बैटरी के कैथोड बनाने के लिए उपयुक्त होते हैं?
Q: निम्नलिखित पदार्थों पर विचार कीजिए :
I. एथेनॉल
II. नाइट्रोग्लिसरीन
III. यूरिया
उपर्युक्त में से कितनों के उत्पादन में कोयला गैसीकरण प्रौद्योगिकी का उपयोग किया जा सकता है?
Q: Consider the following:
1. Battery storage
2. Biomass generator
3. Fuel cell
4. Rooftop solar photovoltaic unit
How many of the above are considered “distributed energy resources”?
Q: With reference to radioisotope thermoelectric generators (RTGs), consider the following statements:
1. RTGs are miniature fission reactors.
2. RTGs are used for powering the onboard systems of spacecrafts.
3. RTGs can use Plutonium-238, which is a by-product of weapons development.
Which of the statements given above are correct?
Q: 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?
Q: With reference to the role of biofilters in Recirculating Aquaculture System, consider the following statements:
1. Biofilters provide waste treatment by removing uneaten fish feed.
2. Biofilters convert ammonia present in fish waste to nitrate.
3. Biofilters increase phosphorus as nutrient for fish in water.
How many of the statements given above are correct?
Q: With reference to green hydrogen, consider the following statements:
1. It can be used directly as a fuel for internal combustion.
2. It can be blended with natural gas and used as fuel for heat or power generation.
3. It can be used in the hydrogen fuel cell to run vehicles.
How many of the above statements are correct?
Q: With reference to street-lighting, how do sodium lamps differ from LED lamps?
1. Sodium lamps produce light in 360 degrees but it is not so in the case of LED lamps.
2. As street-lights, sodium lamps have longer life span than LED lamps.
3. The spectrum of visible light from sodium lamps is almost monochromatic while LED lamps offer significant colour advantages in street-lighting.
Select the correct answer using the code given below.
Q: With reference to solar water pumps, consider the following statements:
1. Solar power can be used for running surface pumps but not for submersible pumps.
2. Solar power can be used for running centrifugal pumps but not the ones with piston.
Which of the statements given above is/are correct?
Q: In the context of proposals to the use of hydrogen-enriched CNG (H-CNG) as fuel for buses in public transport, consider the following statements :
1. The main advantage of the use of H-CNG is the elimination of carbon monoxide emissions.
2. H-CNG as fuel reduces carbon dioxide and hydrocarbon emissions.
3. Hydrogen up to one-fifth by volume can be blended with CNG as fuel for buses.
4. H-CNG makes the fuel less expensive than CNG.
Which of the statements given above is/are correct?
Q: किसी देश के “नाभिकीय आपूर्तिकर्ता समूह” (NSG) का सदस्य बनने का क्या परिणाम है/हैं?
1. इसकी पहुँच नवीनतम और सबसे कुशल परमाणु प्रौद्योगिकियों तक हो जाएगी।
2. यह स्वतः “नाभिकीय आयुध अप्रसार संधि” (NPT) का सदस्य बन जाता है।
उपयुक्त कथनों में से कौन-सा/से सही है/हैं?
Q: With reference to solar power production in India, consider the following statements:
1. India is the third largest in the world in the manufacture of silicon wafers used in photovoltaic units.
2. The solar power tariffs are determined by the Solar Energy Corporation of India.
Which of the statements given above is/are correct?
Q: It is possible to produce algae-based biofuels, but what is/are the likely limitation(s) of developing countries in promoting this industry?
1. Production of algae-based biofuels is possible in seas only and not on continents.
2. Setting up and engineering the algae-based biofuel production requires high level of expertise/technology until the construction is completed.
3. Economically viable production necessitates the setting up of large-scale facilities which may raise ecological and social concerns.
Select the correct answer using the code given below:
Q: Consider the following statements:
1. The Nuclear Security Summits are periodically held under the aegis of the United Nations.
2. The International Panel on Fissile Materials is an organ of International Atomic Energy Agency.
Which of the statements given above is/are correct?
Q: India is an important member of the ‘International Thermonuclear Experimental Reactor’. If this experiment succeeds, what is the immediate advantage for India?
(a)It can use thorium in place of uranium for power generation.
(b)It can attain a global role in satellite navigation.
(c)It can drastically improve the efficiency of its fission reactors in power generation.
(d)It can build fusion reactors for power generation.
Q: With reference to 'fuel cells' in which hydrogen-rich fuel and oxygen are used to generate electricity, consider the following statements:
1. If pure hydrogen is used as a fuel, the fuel cell emits heat and water as by-products.
2. Fuel cells can be used for powering buildings and not for small devices like laptop computers.
3. Fuel cells produce electricity in the form of Alternating Current (AC).
Which of the statements given above is/are correct?
Q: With reference to technologies for solar power production, consider the following statements: 1. 'Photovoltaics' is a technology that generates electricity by direct conversion of light into electricity, while 'Solar Thermal' is a technology that utilizes the Sun's rays to generate heat which is further used in electricity generation process. 2. Photovoltaics generates Alternating Current (AC), while Solar Thermal generates Direct Current (DC). 3. India has manufacturing base for Solar Thermal technology, but not for Photovoltaics. Which of the statements given above is/are correct?
Q: In India, cluster bean (Guar) is traditionally used as a vegetable or animal feed, but recently the cultivation of this has assumed significance. Which one of the following statements is correct in this context?
(a)The oil extracted from seeds is used in the manufacture of biodegradable plastics
(b)The gum made from its seeds is used in the extraction of shale gas
(c)The leaf extract of this plant has the properties of anti-histamines
Q: What is the role of ultraviolet (UV) radiation in the water purification systems?
1. It inactivates/kills the harmful microorganisms in water.
2. It removes all the undesirable odours from the water.
3. It quickens the sedimentation of solid particles, removes turbidity and improves the clarity of water.
Which of the statements given above is/are correct?
Q: To meet its rapidly growing energy demand, some opine that India should pursue research and development on thorium as the future fuel of nuclear energy. In this context, what advantage does thorium hold over uranium?
1. Thorium is far more abundant in nature than uranium.
2. On the basis of per unit mass of mined mineral, thorium can generate more energy compared to natural uranium.
3. Thorium produces less harmful waste compared to uranium.
Which of the statements given above is/are correct?
Q: Microbial fuel cells are considered a source of sustainable energy. Why?
1. They use living organisms as catalysts to generate electricity from certain substrates.
2. They use a variety of inorganic materials as substrates.
3. They can be installed in waste water treatment plants to cleanse water and produce electricity.
Which of the statements given above is/are correct?
Q: What is the difference between a CFL and an LED lamp?
1. To produce light, a CFL uses mercury vapour and phosphor while an LED lamp uses semi-conductor material.
2. The average life span of a CFL is much longer than that of an LED lamp.
3. A CFL is less energy-efficient as compared to an LED lamp.
Which of the statements given above is/are correct?
Q: Where was the first desalination plant in India to produce one lakh litres freshwater per day based on low temperature thermal desalination principle commissioned?
Q: Recently, the European Union and six other countries including India signed the International Thermonuclear Experimental Reactor (ITER) Project. Which one of the following was NOT a signatory to it?
Q: Assertion (A): The main constituent of the Liquefied Petroleum Gas is methane.
Reason (R): Methane can be used directly for burning in homes and factories where it can be supplied through pipelines.
(a)Both A and R are individually true and R is the correct explanation of A
(b)Both A and R are individually true but R is not the correct explanation of A
Q: Match List-I (Atomic Power Plants/Heavy Water Plants) with List-II (State) and select the correct answer using the code given below the lists :
List-I
(A) Thal
(B) Manuguru
(C) Kakrapar
(D) Kaiga
List-II (State)
1. Andhra Pradesh
2. Gujarat
3. Maharastra
4. Maha
5. Karnataka
Q: Consider the following statements:
1. Indira Gandhi Centre for Atomic Research uses fast reactor technology.
2. Atomic Minerals Directorate for Research and Exploration is engaged in heavy water production.
3. Indian Rare Earths Limited is engaged in the manufacture of Zircon for India's nuclear programme beside other rare earth products.
Which of these statements given above are correct?
Q: Match List I (Fuel Gases) with List II (Major Constituents) and select the correct answer using the codes given below:
List I
(A) CNG
(B) Coal gas
(C) LPG
(D) Water gas
List II
1. Carbon monoxide, Hydrogen
2. Butane, Propane
3. Methane, Ethane
4. Hydrogen, Methane, Carbon monoxide
Codes:
Q: Consider the following organisations:
I. Atomic Minerals Directorate for Research and Exploration
II. Heavy Water Board
III. Indian Rare Earths Limited
IV. Uranium Corporation of India
Which of these is/are under the Department of Atomic Energy?
Q: Consider the following statements: In a nuclear reactor, self-sustained chain reaction is possible, because
I. more neutrons are released in each of the fission reactions.
II. the neutrons immediately take part in the fission process.
III. the fast neutrons are slowed down by Graphite.
IV. every neutron released in the fission reaction initiates further fission.
Which of these statements are correct?
Q: Consider the following features of newer models of motor cars:
I. Radial tyres
II. Streamlined body
III. Multipoint fuel injection
IV. Catalytic converter with exhaust
Which of these features make the newer models of motor cars more fuel-efficient?
Q: Consider the following statements regarding a motor car battery:
I. The voltage is usually 12 V.
II. Electrolyte used is hydrochloric acid.
III. Electrodes are lead and copper.
IV. Capacity is expressed in ampere-hour.
Which of the above statements are correct?
Q: Consider the following statements: At the present level of technology available in India, solar energy can be conveniently used to
I. supply hot water to residential buildings.
II. supply water for minor irrigation projects.
III. provide street lighting.
IV. electrify a cluster of villages and small towns.
Of these statements
Q: 113. Which one of the following pairs of materials serves as electrodes in chargeable batteries commonly used in devices such as torchlights, electric shavers, etc.?
Q: ‘Yellow cake’, an item of smuggling across borders is
(a)a crude form of heroin
(b)a crude form of cocaine
(c)uranium oxide
(d)unrefined gold
Frequently Asked Questions
How many UPSC Prelims questions have been asked from Energy & Environment?▼
UPSC has asked 52 questions on Energy & Environment in GS Paper 1 Prelims between 1995 and 2025. This sub-topic falls under Science & Technology.
In which years has UPSC asked about Energy & Environment?▼
Questions on Energy & Environment have appeared in UPSC Prelims in the following years: 2025, 2024, 2023, 2021, 2020, 2019, 2018, 2017, 2016, 2015, 2014, 2012, 2011, 2010, 2009, 2008, 2007, 2006, 2005, 2004, 2001, 2000, 1999, 1998, 1997, 1996, 1995. The topic has appeared in 27 out of 31 years.
What is the difficulty level of Energy & Environment questions in UPSC Prelims?▼
Among 52 questions on Energy & Environment: 16 are easy, 36 are moderate, and 0 are difficult. Most questions test conceptual understanding of the topic.
