CBSE Class 10 · Minerals and Energy Resources

Conventional Sources of Energy Class 10: Coal, Oil, Gas, Electricity

Updated 14 October 2026 · Fact-checked

Conventional energy sources are firewood, cattle dung cake, coal, petroleum, natural gas and electricity (hydel and thermal). Coal is India's most abundant fossil fuel, found mainly in Gondwana rocks of the Damodar valley. Petroleum comes from Mumbai High, Gujarat and Assam; natural gas is found with it. Electricity comes from running water (hydel) or burning fossil fuels (thermal).

Notice that deeper burial and more time turn peat into better coal; bituminous is most popular and anthracite is the highest quality.

Illustration drawn for QuestionBuddy.

Understand Conventional Sources of Energy

Energy and its two classes. Energy is needed to cook, light and heat homes, run vehicles and drive machines. It comes from fuel minerals (coal, petroleum, natural gas, uranium) and electricity. Conventional sources: firewood, cattle dung cake, coal, petroleum, natural gas and electricity (hydel and thermal). Firewood and dung cake are most common in rural India, meeting more than 70 per cent of rural household energy by one estimate, but they are becoming hard to continue because forests are shrinking, and burning dung wastes valuable manure.

Coal.

India's most abundantly available fossil fuel, used for power, industry and homes; India is highly dependent on it for commercial energy.
Formed by compression of plant material over millions of years; its form depends on compression, depth and time of burial:
Peat: from decaying plants in swamps; low carbon, high moisture, low heating capacity.
Lignite: low-grade brown coal, soft, high moisture; main reserves at Neyveli (Tamil Nadu), used for electricity.
Bituminous: buried deep at higher temperatures; the most popular commercial coal. Metallurgical coal is high-grade bituminous coal, valuable for smelting iron in blast furnaces.
Anthracite: the highest quality hard coal.
Two geological ages: Gondwana (a little over 200 million years) and tertiary (about 55 million years).
Gondwana coal (metallurgical) is mainly in the Damodar valley (West Bengal-Jharkhand): Jharia, Raniganj, Bokaro; also in the Godavari, Mahanadi, Son and Wardha valleys.
Tertiary coal is in Meghalaya, Assam, Arunachal Pradesh and Nagaland.
Coal is bulky and loses weight as it turns to ash, so heavy industries and thermal power stations are located on or near coalfields.

Petroleum.

The next major energy source after coal. Gives fuel for heat and light, lubricants, and raw materials for many industries. Refineries are a 'nodal industry' for synthetic textile, fertiliser and chemical industries.
Most occurrences are in anticlines and fault traps in tertiary rocks. In an anticline (upfold), oil is trapped in the crest; the oil layer is porous limestone or sandstone, held between non-porous layers. Gas, being lighter, usually lies above the oil.
Major areas: Mumbai High, Gujarat and Assam. Ankeleshwar is Gujarat's most important field. Assam is the oldest oil-producing state, with Digboi, Naharkatiya and Moran-Hugrijan.

Natural gas.

Found with petroleum; used as domestic and industrial fuel, to generate electricity, for industrial heating, as raw material for chemical, petrochemical and fertiliser industries, and as CNG (transport) and PNG (cooking).
Reserves: Mumbai High and allied west-coast fields, the Cambay basin, and new finds in the Krishna-Godavari basin.
The first 1,700 km Hazira-Vijaipur-Jagdishpur (HVJ) pipeline by GAIL (India) linked Mumbai High and Bassein gas fields with fertiliser, power and industrial complexes in western and northern India. Pipelines have grown to 18,500 km and are expected to exceed 34,000 km as a national Gas Grid.

Electricity.

Per capita consumption of electricity is an index of development.
Hydel: fast-flowing water drives turbines; a renewable resource (Bhakra Nangal, Damodar Valley Corporation, Kopili Hydel Project).
Thermal: burning coal, petroleum or natural gas drives turbines; uses non-renewable fossil fuels. Once generated, the electricity is exactly the same.

Map work (2026-27). Identify coal mines: Raniganj, Bokaro, Talcher, Neyveli. Identify oil fields: Digboi, Naharkatia, Mumbai High, Bassien, Kalol, Ankaleshwar. Locate and label thermal power plants: Namrup, Singrauli, Ramagundam. (Nuclear plants are on the non-conventional energy page, since NCERT counts atomic energy as non-conventional.)

Conventional Sources of Energy: key facts

Conventional sources: Firewood, cattle dung cake, coal, petroleum, natural gas, electricity (hydel and thermal); Atomic energy is non-conventional in NCERT.
Coal types: Peat low carbon, high moisture
Lignite brown, Neyveli
Bituminous most used, metallurgical grade for blast furnaces
Anthracite highest quality; Listed in rising order of quality: peat < lignite < bituminous < anthracite. Rising compression, depth, time.
Coal ages: Gondwana (>200 million years; Damodar valley: Jharia, Raniganj, Bokaro) vs tertiary (~55 million years; Meghalaya, Assam, Arunachal, Nagaland)
Petroleum: Anticlines and fault traps in tertiary rocks; Mumbai High, Gujarat (Ankeleshwar), Assam (Digboi, Naharkatiya, Moran-Hugrijan; oldest); Refineries: nodal industry.
Natural gas: Mumbai High, Cambay basin, Krishna-Godavari basin; HVJ pipeline 1,700 km by GAIL; CNG for transport, PNG for cooking.
Electricity: Hydel (running water, renewable) vs thermal (coal, oil, gas; non-renewable); per capita use = index of development
Map list: Coal: Raniganj, Bokaro, Talcher, Neyveli. Oil: Digboi, Naharkatia, Mumbai High, Bassien, Kalol, Ankaleshwar. Thermal: Namrup, Singrauli, Ramagundam

Peat	low carbon, high moisture
Lignite	brown, Neyveli
Bituminous	most used, metallurgical grade for blast furnaces
Anthracite	highest quality

How to answer Conventional Sources of Energy questions

This topic carries map work and theory: MCQs on coal types and fields, 2-mark distinctions (hydel vs thermal, Gondwana vs tertiary), 5-mark descriptions of coal or petroleum, case passages and map identification.

1For coal types, order them by quality and give one feature each.
2For coal distribution, split by age: Gondwana (Damodar valley and other valleys) and tertiary (north-east).
3For petroleum occurrence, explain anticlines and fault traps with porous and non-porous layers.
4For locations of industry, use the bulky-coal reason.
5For electricity, contrast source, renewability and examples of hydel and thermal.
6For maps, group items: coal mines in the east and south, oil fields in Assam and Gujarat-Mumbai, thermal plants in Assam, MP and Telangana.

Conventional Sources of Energy in real life

The idea, met in an everyday situation. Answer the question in your own words, then compare with the model answer. The one-line hook is what to remember.

Why heavy industry sits near coalfields

Suppose a company must choose where to build a steel plant: near a coalfield in Jharkhand, or near a city 800 km away where its managers prefer to live.

Using NCERT's reasoning about coal, advise the company.

Try it first, then show the solutionSolution

Recall that coal is bulky and loses weight on use as it turns to ash.
Moving bulky raw material long distances is costly.
So heavy industries and thermal power stations are located on or near coalfields.

Answer: The company should build near the coalfield. Coal is bulky and loses weight when burnt, as much of it turns to ash, so carrying it 800 km would waste money on transporting material that does not end up in the product. That is why heavy industries and thermal power stations are located on or near coalfields such as those of the Damodar valley.

Memory hook: Don't carry ash: build where the coal is.

Tricks to remember Conventional Sources of Energy

Short memory aids. Say each one aloud once, then use it on a question the same day.

P-L-B-A
Peat, Lignite, Bituminous, Anthracite: 'Poor Little Black Ants' climb from worst to best.
Use it when: Coal types in order.
Gondwana is Grand-old
Gondwana > 200 million years (Damodar); tertiary only 55 million (North-east).
Use it when: Coal ages.
Assam = oldest oil
Digboi was first: Assam is the oldest oil-producing state.
Use it when: Petroleum MCQs.
N-S-R thermal
Namrup (Assam), Singrauli (MP), Ramagundam (Telangana).
Use it when: Map list.

Conventional Sources of Energy: solved examples

Ordered from board level to HOTS. Try each one before you open the solution.

Example 1: Lignite reserves · 1 mark · MCQBoard level

The principal lignite reserves of India are located at:
(a) Jharia
(b) Raniganj
(c) Neyveli
(d) Talcher

Try it first, then show the solutionSolution

NCERT names Neyveli in Tamil Nadu as the main lignite reserve (1 mark).

Answer: (c) Neyveli

Example 2: Hydel vs thermal (2 marks) · 2 marks · Very short answerBoard level

Distinguish between hydroelectricity and thermal electricity. (2 marks)

Try it first, then show the solutionSolution

Hydel power is generated by fast-flowing water driving turbines; it uses a renewable resource, e.g., Bhakra Nangal (1 mark).
Thermal power is generated by burning coal, petroleum or natural gas to drive turbines; it uses non-renewable fossil fuels (1 mark).

Answer: Hydroelectricity is produced when fast-flowing water drives turbines, so it uses a renewable resource, as at Bhakra Nangal. Thermal electricity is produced by burning coal, petroleum or natural gas, which are non-renewable fossil fuels.

Example 3: Assertion-reason: thermal plants near coalfields · 1 mark · Assertion-reasonHarder board level

Assertion (A): Thermal power stations are usually located on or near coalfields.
Reason (R): Coal is a bulky material that loses weight on use as it is reduced to ash.
(a) Both A and R are true, and R is the correct explanation of A.
(b) Both A and R are true, but R is not the correct explanation of A.
(c) A is true, but R is false.
(d) A is false, but R is true.

Try it first, then show the solutionSolution

NCERT gives R as the reason for A (1 mark).

Answer: (a) Both A and R are true, and R is the correct explanation of A.

Example 4: Coal in India (5 marks) · 5 marks · Long answerHarder board level

'The quality and location of India's coal are products of its geological history.' Examine the statement with reference to the types of coal and their distribution by geological age. (5 marks)

Try it first, then show the solutionSolution

Coal forms by compression of plant material; peat has low carbon, high moisture and low heating capacity (1 mark).
Lignite is low-grade brown coal with high moisture, found mainly at Neyveli and used for electricity (1 mark).
Bituminous coal is the most popular commercial coal; its high-grade metallurgical form smelts iron; anthracite is the highest quality (1 mark).
Gondwana coal (over 200 million years), mostly metallurgical, is in the Damodar valley (Jharia, Raniganj, Bokaro) and the Godavari, Mahanadi, Son and Wardha valleys (1 mark).
Tertiary coal (about 55 million years) is in Meghalaya, Assam, Arunachal Pradesh and Nagaland (1 mark).

Answer: Coal forms from plant material compressed over millions of years, and its type depends on compression, depth and time. Peat, from swamp plants, has low carbon, high moisture and low heating capacity. Lignite is a soft, moist, low-grade brown coal, found mainly at Neyveli in Tamil Nadu and used for power. Bituminous coal, buried deeper, is the most widely used; its high-grade metallurgical form smelts iron in blast furnaces. Anthracite is the best hard coal. By age, Gondwana coal, over 200 million years old and mostly metallurgical, lies in the Damodar valley at Jharia, Raniganj and Bokaro, and in the Godavari, Mahanadi, Son and Wardha valleys. Tertiary coal, about 55 million years old, occurs in Meghalaya, Assam, Arunachal Pradesh and Nagaland.

Example 5: Case: the HVJ pipeline · 4 marks · Case-basedHOTS / competency

Read the case and answer the questions.

NCERT notes that the first cross-country gas pipeline, the 1,700 km Hazira-Vijaipur-Jagdishpur (HVJ) line built by GAIL (India), linked the Mumbai High and Bassein gas fields with fertiliser, power and industrial complexes in western and northern India. This artery gave a push to India's gas market. Since then, cross-country pipelines have grown to about 18,500 km, and a national Gas Grid of over 34,000 km is planned, linking gas sources and markets including the north-eastern states.

(i) Which organisation built the HVJ pipeline? (1)
(ii) Name the two gas fields linked by it. (1)
(iii) Why is natural gas valuable to the industries the pipeline serves? (2)

Try it first, then show the solutionSolution

(i) GAIL (India) (1 mark).
(ii) Mumbai High and Bassein (1 mark).
(iii) It is a fuel for power generation and for heating in industries (1 mark).
(iii) It is a raw material for chemical, petrochemical and fertiliser industries, so pipelines let these plants work far from the gas fields (1 mark).

Answer: (i) GAIL (India). (ii) Mumbai High and Bassein. (iii) Natural gas is a fuel for generating electricity and for industrial heating, and a raw material for chemical, petrochemical and fertiliser industries. The pipeline lets such plants in western and northern India use gas from distant fields.

Example 6: Map: oil fields and thermal plants · 3 marks · Map workHarder board level

On an outline map of India: (a) identify the oil field marked in north-eastern Assam that is in the official list along with Naharkatia; (b) locate and label the thermal power plant at Ramagundam; (c) identify the offshore oil field west of Mumbai. (3 marks)

Try it first, then show the solutionSolution

(a) Digboi, in north-eastern Assam (1 mark).
(b) Ramagundam, in Telangana, marked with a dot and labelled (1 mark).
(c) Mumbai High, offshore in the Arabian Sea (1 mark).

Answer: (a) Digboi; (b) Ramagundam (Telangana), dotted and labelled; (c) Mumbai High.

Where students lose marks in Conventional Sources of Energy

The slips examiners see most often, and what to write instead.

Mistake: Listing atomic energy as conventional
It produces electricity like thermal plants.
Wrong working
Conventional sources include coal, oil and nuclear energy.
Right working
NCERT lists atomic energy among non-conventional sources.
Do this: Follow the NCERT lists.
Usually costs: 1 mark.
Mistake: Swapping Gondwana and tertiary coal
Two geological ages.
Wrong working
Tertiary coal is found in the Damodar valley.
Right working
Gondwana in the Damodar valley; tertiary in the North-east.
Do this: Gondwana is Grand-old and central.
Usually costs: 1 mark.
Mistake: Calling Gujarat the oldest oil state
Gujarat and Mumbai produce more today.
Wrong working
Gujarat is the oldest oil-producing state.
Right working
Assam is the oldest.
Do this: Digboi first.
Usually costs: 1 mark.
Mistake: Map items outside the list
Students add Jharia or Moran.
Wrong working
Labelling Jharia in a map question from the list.
Right working
Coal list: Raniganj, Bokaro, Talcher, Neyveli.
Do this: Practise only the listed items.
Usually costs: Accuracy.

Exam tips

Map items from this chapter are many: practise coal mines, oil fields and thermal plants on blank maps weekly.
Use the 'bulky coal' reason in any industrial location answer.
Learn one feature per coal type for MCQs and the 5-mark answer.
Geography has no 3-mark answers in 2026-27.

Practice questions on Conventional Sources of Energy

Write each answer on paper first. Open the hint only if you are stuck, and the answer only when you have finished.

Q1 · 1 mark · MCQBoard level
Which is the highest quality hard coal?
(a) Peat
(b) Lignite
(c) Bituminous
(d) Anthracite
Hint
Last in the P-L-B-A order.
Answer
(d) Anthracite
Q2 · 2 marks · Very short answerHarder board level
Explain how petroleum occurs in anticlines. (2 marks)
Hint
Crest of the upfold; porous and non-porous layers.
Answer
In folded regions, oil is trapped in the crest of the upfold (anticline or dome). The oil-bearing layer is porous limestone or sandstone, and non-porous layers above and below stop the oil from rising or sinking; gas lies above the oil.
Q3 · 2 marks · Very short answerHarder board level
Why are petroleum refineries called a 'nodal industry'? (2 marks)
Hint
Which industries depend on them?
Answer
Refineries supply raw materials for synthetic textile, fertiliser and numerous chemical industries, so many industries grow around them. They act as a node linking these industries.
Q4 · 2 marks · Very short answerHOTS / competency
Suppose a village still depends on firewood and dung cakes for cooking. Using NCERT, explain two problems with this and one conventional alternative. (2 marks)
Hint
Forests and manure; then LPG/PNG or electricity.
Answer
Firewood use is becoming difficult as forest area decreases, and burning dung cake wastes valuable manure needed for farming. Natural gas as cooking fuel (PNG) or electricity could replace them.
Q5 · 5 marks · Long answerHarder board level
Why are India's petroleum and natural gas concentrated in only a few regions? Examine with reference to how they occur and where they are found. (5 marks)
Hint
Three oil regions with fields; gas basins; pipeline.
Answer
Petroleum is India's next major energy source after coal. Most of it occurs in anticlines and fault traps in tertiary rocks. Mumbai High, Gujarat and Assam are the main producing areas; Mumbai High is offshore in the west, Ankeleshwar is Gujarat's most important field, and Assam, the oldest oil-producing state, has Digboi, Naharkatiya and Moran-Hugrijan. Natural gas occurs with petroleum. Its major reserves are in Mumbai High and allied west-coast fields, supplemented by the Cambay basin, with new reserves in the Krishna-Godavari basin on the east coast. The HVJ pipeline built by GAIL links Mumbai High and Bassein gas with markets in western and northern India.
Q6 · 1 mark · Assertion-reasonHOTS / competency
Assertion (A): The per capita consumption of electricity is considered an index of development.
Reason (R): Electricity has a very wide range of applications in today's world.
(a) Both A and R are true, and R is the correct explanation of A.
(b) Both A and R are true, but R is not the correct explanation of A.
(c) A is true, but R is false.
(d) A is false, but R is true.
Hint
Why does NCERT say this?
Answer
(a) Both A and R are true, and R is the correct explanation of A.
Q7 · 3 marks · Map workBoard level
On an outline map of India, identify the coal mines from the official list that lie in Odisha, in Tamil Nadu and in Jharkhand. (3 marks)
Hint
One is lignite; the Jharkhand one is in the Damodar valley.
Answer
Odisha: Talcher. Tamil Nadu: Neyveli. Jharkhand: Bokaro.

Test your recall

Answer in your head or on paper first, then open the card. Pulling an answer out of memory makes it stick far better than re-reading.

1.Which is the most abundantly available fossil fuel in India?Show answer
Coal.
2.Name two important Damodar valley coalfields.Show answer
Any two of Jharia, Raniganj, Bokaro.
3.Which is the most important oil field of Gujarat?Show answer
Ankeleshwar.
4.Where are new natural gas reserves found on the east coast?Show answer
The Krishna-Godavari basin.
5.Name a hydel project from NCERT.Show answer
Bhakra Nangal, Damodar Valley Corporation or Kopili Hydel Project.

Conventional Sources of Energy: frequently asked questions

What are conventional sources of energy?

Firewood, cattle dung cake, coal, petroleum, natural gas and electricity from hydel and thermal plants.

What are the types of coal in Class 10 Geography?

Peat, lignite, bituminous (including metallurgical coal) and anthracite, in increasing order of quality.

Which coal mines, oil fields and thermal plants are in the 2026-27 map list?

Coal: Raniganj, Bokaro, Talcher, Neyveli. Oil: Digboi, Naharkatia, Mumbai High, Bassien, Kalol, Ankaleshwar. Thermal: Namrup, Singrauli, Ramagundam.

Where is petroleum found in India?

Mainly in Mumbai High, Gujarat (Ankeleshwar) and Assam (Digboi, Naharkatiya, Moran-Hugrijan).