UPSC Prelims 2023 Q66: Coal Thermal Power Plants in India — Explained
With reference to coal-based thermal power plants in India, consider the following statements:
1. None of them uses seawater.
2. None of them is set up in water-stressed district.
3. None of them is privately owned.
How many of the above statements are correct?
- Only one
- Only two
- All three
- None
Answer: (d) None
Statement-wise explanation
- 1: incorrect — Several coastal coal plants in India draw seawater for once-through condenser cooling. Tata Power's 4,000 MW Mundra Ultra Mega Power Project in Gujarat is one example. The rules name these plants directly: MoEFCC's December 2015 water-consumption limits were amended in June 2018 to exempt plants that use seawater. That exemption only makes sense if such plants exist.
- 2: incorrect — Many coal plants stand in water-scarce districts. The Centre for Science and Environment (CSE) estimates that about 48% of India's coal power capacity is in such districts. Examples include Nagpur and Chandrapur in Maharashtra, Raichur in Karnataka, Korba in Chhattisgarh and Barmer in Rajasthan. WRI has also found that freshwater-cooled plants in high water-stress areas run at lower capacity factors.
- 3: incorrect — Coal power in India is owned by three sectors: Central (NTPC and others), State (state generation companies) and Private. Central Electricity Authority (CEA) data puts private coal capacity at roughly 73 GW, about one-third of the total. Adani Power, Tata Power, JSW Energy and Reliance Power are all private owners.
How to eliminate
All three statements begin with the absolute word 'None'. One counter-example is enough to make each one false. A candidate can find those counter-examples from general knowledge. (1) India has a long coastline with large plants at Mundra, Udupi and Tuticorin, and coastal plants worldwide cool with seawater. (2) Coal plants are built near coalfields in central India, which is also dry, drought-prone country. (3) Adani Power and Tata Power are household names, and the power sector has been open to private generators since the 1990s and the Electricity Act, 2003. Once statement 3 is plainly false, a candidate who doubts 'None' in the other two can confidently pick the answer that no statement is correct. Rule to remember: a 'none of them' claim about a large, varied Indian sector is almost always false.
Know more
How coal plants use water and who owns them
A coal plant boils water into steam to spin a turbine. The steam is then condensed, and cooling the condenser uses most of the plant's water.
| Cooling method | How it works | Water use | Where used |
|---|---|---|---|
| Once-through | Draws river or sea water, passes it through the condenser once, discharges it warm | Very high withdrawal, low consumption | Older plants; coastal plants on seawater |
| Closed-loop (cooling tower) | Recirculates water; losses are evaporation and blowdown | Moderate | Most inland plants |
| Air-cooled condenser (ACC) | Air cools the steam; almost no cooling water | Very low | Dry areas; NTPC North Karanpura and Patratu |
Water rules (MoEFCC)
- Notification of 7 December 2015: once-through plants had to install cooling towers. Existing plants were capped at 3.5 m³/MWh. Plants installed from 1 January 2017 were capped at 2.5 m³/MWh, with zero liquid discharge.
- Amendment of 28 June 2018: seawater-based plants were exempted from the consumption limits.
- Plants within 50 km of a sewage treatment plant must use treated sewage water.
Ownership of coal capacity (CEA, 2026: about 224 GW in total)
| Sector | Approx. share | Examples |
|---|---|---|
| Central | ~1/3 | NTPC, DVC, NLC |
| State | ~1/3 | MAHAGENCO, TANGEDCO, RRVUNL |
| Private | ~1/3 | Adani Power, Tata Power, JSW Energy |
Why water stress matters: many coal plants sit in water-scarce districts, so a weak monsoon or a heatwave can shut units down. This is why ACCs, treated sewage water and dry ash handling are pushed as solutions.
NCERT Concepts to Revise
- Falkenmark indicator: Statement 2 turns on what 'water-stressed' means; the Falkenmark indicator is a standard way to measure water scarcity.
- Recycling and reuse of water: Rules make plants near sewage treatment plants reuse treated sewage, a direct response to water stress at thermal plants.