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Wind, hydro and other renewables
Wind, hydro and the other renewables: onshore and offshore wind, large and small hydropower and the risks of building in the Himalaya, geothermal energy, and energy from tides, waves and ocean heat. It serves GS3 answers on energy and infrastructure.
All 4 subjects shown; the 1 that changed from 16 to 31 July 2026 are marked.Show only these
Geothermal energy and Puga Valley
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Geothermal energy taps heat that is already in the ground, so a well is an exploration job before it is a power project. The ONGC Energy Centre, set up by the Oil and Natural Gas Corporation, commissioned India's first two at Puga Valley in Ladakh, drilled in July 2026.
- They are assessment wells: they will evaluate the reservoir for India's first 1 MW demonstration geothermal power project.
- Unlike solar and wind, geothermal power is available round the clock.
Heat
Radioactive decay of uranium, thorium and potassium, and heat left from the Earth's formation
Reservoir
Where faults let hot material rise, hot water and steam collect in permeable rock
Power
Wells bring it up to drive a turbine, with no fuel burnt
What changed
4 Sep 2026
4 Sep 2026
- The National Policy on Geothermal Energy has the Ministry of New and Renewable Energy as its nodal ministry.
- It covers exploration, direct use, ground source heat pumps and the repurposing of abandoned oil and gas wells.
Wind energy in India
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India ranks fourth in the world in installed wind capacity, led by Gujarat, Tamil Nadu, Karnataka, Maharashtra and Rajasthan.
What changed
22 Jul 2026New subject
- Installed wind capacity was 57,443 MW on 30 June 2026, and generation rose to 106 billion units in 2025 to 26 from 83 billion in each of the two earlier years.
- India ranked fourth in the world in cumulative wind capacity at the end of 2025. Gujarat leads the States, followed by Tamil Nadu, Karnataka, Maharashtra and Rajasthan.
Hydropower
Small hydro power
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A stream that falls steeply enough will turn a turbine with no reservoir behind it, which is the whole case for building small.
- Small hydro in India means a project of up to 25 MW, usually run of river, using a stream's natural fall rather than a large reservoir.
Why small hydro
- Run of river designs need relatively little land
- No large scale submergence or displacement
- Power close to where it is used, in remote terrain
The barriers
- Long lead times
- Delays in forest, environment and right of way clearances
- Hard to finance, so the Indian Renewable Energy Development Agency was urged to bring in long term patient capital
What changed
10 Sep 2026
10 Sep 2026
- A Small Hydro Power Development Scheme was proposed for 2026–27 to 2030–31, at ₹2,584.60 crore for about 1,500 MW.
- It builds no plant: it pays States to prepare Detailed Project Reports, so the pipeline exists before the money does.
Hydropower in the Himalaya
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The mountains hold most of the fall a turbine wants and most of the hazard a project cannot survive.
- The Himalaya is young, steep and seismically active, so a glacial lake burst or a landslide reaches a project built in the valley below it.
- Nepal's 26 August flood destroyed two hydropower projects and damaged at least thirteen under construction, and the damage was blamed less on the trigger than on where the projects sat.
- A cumulative impact assessment weighs every project on a river basin together, rather than clearing each one on its own.
- Neither Nepal nor India assesses Himalayan projects basin by basin, so each clearance ignores what the others have already done.
- The World Commission on Dams reported in 2000 that a dam's costs fall on the people nearest it while its benefits travel, which is the argument still being had.
What changed
Background reading: The Indian Express, 30 Aug 2026: Nepal floods: The red flags in dam-building in the Himalayas (opens in a new tab) · The Indian Express, 1 Sep 2026: Express in Nepal: How hydropower firm is planning search for missing staff (opens in a new tab)
See also: Gram sabha consent for forest clearance
Also filed elsewhere
- Pumped storage · on Storage, batteries and electric mobility
Solar power arrives in the afternoon and demand peaks after dark, and the oldest way to carry it across those hours is to carry water uphill.