Hydroelectric Power

• Hydraulic power can be captured from the downward flow of water from higher to lower levels to turn turbines and generate energy.
• The generated energy is directed to a substation, where transformers increase the voltage before its transmission to the grid.
• Hydropower is the cheapest and cleanest source of energy.
• Big dams have environmental and social issues, as seen in projects like Tehri and Narmada, while small hydropower is free from these problems.
• India has 197 hydro power plants.
• Electricity was first commissioned in Darjeeling in 1897, and a hydro power station at Sivasamudram in Karnataka was commissioned in 1902.

Types of hydro power stations

• There are three types of hydropower facilities: impoundments, diversion, and pumped storage.
• Impoundment facilities use a dam to store river water in a reservoir. Water released from the reservoir flows through a turbine, which in turn activates a generator to produce electricity.
• Diversion facilities channel a portion of a river through a canal or penstock and then flow through a turbine to generate electricity. It may not require the use of a dam.
• Pumped storage facilities store electricity generated by other power sources like solar, wind, and nuclear for later use. During periods of high electrical demand, the water is released back to the lower reservoir and turns into a turbine, generating electricity.
• Hydro power projects in India are categorized based on installed capacity: micro, mini, small, and mega.
  • Micro: upto 100 KW
  • Mini: 101KW to 2 MW
  • Small: 2 MW to 25 MW
  • Mega: Hydro projects with installed capacity >= 500 MW
  • Thermal Projects with installed capacity >=1500 MW
• Small Hydro Power (SHP) projects are those with up to 25 MW station capacities.
• The Ministry of Power is responsible for large hydro projects, while the Ministry of New and Renewable Energy handles small hydro power projects.

Small hydro power (SHP)

• Small hydro projects have an installed capacity of less than 25 MW
• They are often run-of-river with small dams or weirs
• Run-of-river installations have less adverse effects on the environment compared to large-scale hydro projects
• Small hydropower plants can serve the energy needs of remote rural areas independently
• India and China are major players in the small hydro sector with the highest number of installed projects.

Advantages of hydropower

• Renewable source of energy that uses and does not consume water, leaving it available for other uses
• Cheaper than electricity generated from coal and gas fired plants with very little recurring cost and no high long term expenditure
• More reliable and reduces financial losses due to frequency fluctuations, as it does not rely on fossil fuels
• Quick starting and closing capabilities make it a preferred solution for meeting peak loads in grids
• Balanced mix of hydro and thermal stations helps in optimal utilization of capacity
• Seasonal load curves of regional grids match with the pattern of hydro power generation, making it well-suited to meet the needs of heavy agricultural loads during high generation periods, and acting as peak load stations during winter months.
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Disadvantages of Hydroelectric power

• Hydropower generation is highly capital-intensive.
• Diversion of forest land is sometimes unavoidable, as hydropower projects are primarily located in hilly areas where forest cover is comparatively better than plain areas.
• Hydropower projects can cause submergence of land, thereby leading to loss of flora and fauna, and large scale displacement.
• Dams can only be built at specific locations, limiting their potential for widespread use.
• Large areas of agriculture may be submerged underwater due to hydropower projects.
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Hydropower Scenario in India

• India is the 5th largest country globally in terms of installed hydroelectric power capacity.
• As of March 2020, India’s installed utility-scale hydroelectric capacity was 46,000 MW or 12.3% of its total utility power generation capacity.
• An additional smaller hydroelectric power units with a total capacity of 4,683 MW (1.3% of its total utility power generation capacity) have been installed.
• India’s estimated hydropower potential is 148,700 MW, excluding small hydro projects.
• In the fiscal year 2019-20, the total hydroelectric power generated in India was 156 TWh (excluding small hydro) with an average capacity factor of 38.71%.
• Hydropower potential is mainly located in northern and north-eastern regions, with Arunachal Pradesh having the largest unexploited potential of 47 GW, followed by Uttarakhand with 12 GW.
• India has over 90 GW of pumped storage potential, with 63 sites identified and recognized in national energy policies for their valuable grid services.
• The estimated potential of Small Hydropwer is 21,135.37 MW from 7,135 sites for power generation in the country.
• India also imports surplus hydroelectric power from Bhutan.
• The public sector accounts for 92.5% of India’s hydroelectric power production, but the private sector is expected to grow in the Himalayan mountain ranges and northeast regions of India.

Issues in Hydropower generation

• Hydroelectric power potential from certain river basins in central India has not been developed due to potential opposition from tribal population.
• Hydropower’s share in electricity generation in India has been decreasing and currently accounts for around 10%.
• Delays in current hydropower projects are due to complex planning procedures, land acquisition and resettlement issues, lack of infrastructure, insufficient market scope and long-term financing.
• Several hydroelectric projects in India are facing contractual conflicts, environmental litigations, local disturbances, financial stress and unwilling purchasers.
• Only about 10,000 MW of hydropower capacity has been added in India in the last 10 years.
• Conflicts among riparian states often delay the construction of hydropower projects in India.

Clearance issues

• Environmental clearance is necessary for HEPs
• Several HEPs have been dropped or modified due to environmental considerations
• Parameters such as e-flow, free flow stretch, eco-sensitive zone, and impact on wild flora and fauna are now better defined
• Hydropower potential should be reassessed using modern technology and environmental considerations
• HEPs with capital expenditure above ?1000 crore require the concurrence of the CEA
• Site-specific changes during construction need approval
• Clearance for HEPs takes an inordinately long time
• Processes must be revisited to reduce the time taken for the TEC
• A unit of the CWC may be co-located within CEA to improve the clearance process
• HEPs have large-scale socio-economic and environmental implications
• HEPs often encounter geological surprises during construction
• The land acquisition process for HEPs is elaborate and requires public hearing and approval of the Gram Sabha
• Resettlement and rehabilitation (R&R) issues are sensitive and entail substantial cost
• Adequate R&R cost should be made integral part of the project cost
• The project management team should include experts from social science, environment, and communication
• Allocating HEPs after obtaining requisite clearances on the pattern of Ultra Mega Power Projects would avoid undue delay and cost overrun.

Financial aspects

• HEPs require roads and bridges for project implementation, which can provide development opportunities for neighboring areas
• The government provides budgetary support for HEPs, but the process needs to be streamlined
• Large HEPs perform flood moderation, but they do not get any grant unless declared a national project by the Ministry of Water Resources
• The government has allowed debt repayment period and project life as 18 years and 40 years respectively, and has introduced an escalating tariff of 2% annually to reduce the initial tariff
• Requisite changes in tariff regulations are required to operate HEPs
• Geological surprises, R&R issues, and environmental factors result in unforeseen situations, which lead to delays in implementation and unnecessary litigation
• A mechanism for quick resolution of contractual conflicts must be developed to fast-track implementation of HEPs

Solutions for Hydropower

• India aims to have 40% of its installed capacity from non-fossil fuel sources by 2030.
• India pursues a renewable target of 175 GW by 2022 and 450 GW by 2030.
• Hydropower is highly relevant for grid integration of renewable energy and for balancing infirmities.
• The 2008 Hydro Power Policy and the 2016 National Tariff Policy encourage private sector participation in hydropower projects.
• The Central Electricity Authority (CEA) and Ministry of Power are actively monitoring and fast-tracking priority schemes, notably the 50,000 MW Hydro Electric Initiative.
• Large hydropower projects built after March 2019 are recognised as renewable and can benefit from the renewable purchase obligation.
• Policy proposals include new ancillary service markets, full renewable status for hydropower with separate purchase obligation benefits, and more integrated planning.
• Draft policies under preparation are expected to support stalled hydropower projects and private sector uptake, and could include measures to make hydropower tariffs more competitive.
• In 2020, the hydropower sector restored electricity to tens of millions following a huge plunge in demand.
• In 2019, the Teesta-V hydropower station in Sikkim was rated as an example of international good practice in hydropower sustainability.
• The Draft Electricity (Amendment) Bill 2020 could make hydropower purchase obligation (HPO) a reality soon.

Way Forward

• However, a better option is re-engineering of the power market to treat hydropower as a peaking and grid-balancing power, and also to distribute its higher tariff over the entire energy consumption on a prorated basis.

List of Hydroelectric Power Plants in India

States	River	Hydroelectric Power Plant
Andhra Pradesh	Krishna	Nagarjunasagar Hydro Electric Power plant
Andhra Pradesh	Krishna	Srisailam Hydro Electric Power plant
Andhra Pradesh, Orissa	Machkund	Machkund Hydro Electric Power plant
Gujarat	Narmada	Sardar Sarovar Hydro Electric Power plant
Himachal Pradesh	Baira	Baira-Siul Hydroelectric Power plant
Himachal Pradesh	Sutlej	Bhakra Nangal Hydroelectric Power plant
Himachal Pradesh	Beas	Dehar Hydroelectric Power plant
Himachal Pradesh	Sutlej	Nathpa Jhakri Hydroelectric Power plant
Jammu and Kashmir	Chenab	Salal Hydro Electric Power plant
Jammu and Kashmir	Jhelum	Uri Hydro Electric Power plant
Jharkhand	Subarnarekha	Subarnarekha Hydroelectric Power plant
Karnataka	Kalinadi	Kalinadi Hydro Electric Power plant
Karnataka	Sharavathi	Sharavathi Hydroelectric Power plant
Karnataka	Kaveri	Shivanasamudra Hydroelectric Power plant
Kerala	Periyar	Idukki Hydro Electric Power plant
Madhya Pradesh	Sone	Bansagar Hydroelectric Power plant
Madhya Pradesh	Narmada	Indira Sagar Hydro Electric Power plant
Madhya Pradesh, Uttar Pradesh	Rihand	Rihand Hydroelectric Power plant
Maharashtra	Koyna	Koyna Hydroelectric Power plant
Manipur	Leimtak	Loktak Hydro Electric Power plant
Odisha	Sileru	Balimela Hydro Electric Power plant
Odisha	Mahanadi	Hirakud Hydro Electric Power plant
Sikkim	Rangit	Rangit Hydroelectric Power plant
Sikkim	Teesta	Teesta Hydro Electric Power plant
Uttarakhand	Bhagirathi	Tehri Hydro Electric Power plant
Himachal Pradesh	Baspa	Baspa-II Hydro Electric Power plant
Himachal Pradesh	Satluj	Nathpa Jhakri Hydro Electric Power Plant
Himachal Pradesh	Beas	Pandoh Dam
Himachal Pradesh	Ravi	Chamera-I
Himachal Pradesh	Ravi	Chamera-II
Himachal Pradesh	Beas	Pong
Jammu and Kashmir	Chenab	Dulhasti

Facts about Hydroelectric Power plants in India

• The Koyna Hydroelectric Project is the largest completed hydroelectric power plant in India. It has a power capacity of 1960 MW.
• The first hydroelectric power station was the Shivanasamudra hydroelectric power station.
• Tehri Hydro Electric Power plant is the highest hydroelectric power project in the country, also Tehri Dam is the tallest one in India. Now, NTPC has taken over the project (Since 2019).
• Srisailam Hydro Power Plant is the third largest working project in India.
• Nathpa Jhakri Hydroelectric Power Plant is the biggest underground hydroelectric power project in the country.
• Sardar Sarovar Dam is the world’s second-largest concrete dam.