PURULIA PUMPED STORAGE PROJECT (PPSP)

The Purulia Pumped Storage Project (PPSP) is the country’s first closed-loop pumped storage power plant with an installed capacity of 900 MW (4 × 225 MW).

The project is situated in the Ayodhya Hills region under the Bagmundi block in Purulia District of West Bengal, India.

Main Project work started in May 2002 and completed on 17.12.2007 well within the scheduled completion date of 31.12.2007. PPSP Project completion cost is Rs. 2491.38 Cr against the revised project cost of Rs 2952 Cr.

The project cost was funded as a loan assistance from the Japan Bank for International Cooperation (JICA) and grant from Govt. of West Bengal.

Since its commissioning in 2007, the PPSP has played a vital role in maintaining grid stability and meeting peak electricity demand.

The project operates on a closed-loop hydroelectric mechanism, wherein water is continuously recycled between two reservoirs situated at different elevations.

One of the key advantages of PPSP is its quick response capability. In the event of a power shortfall in the grid, particularly during peak hours, the plant can commence electricity generation within five minutes. This rapid start-up feature enhances grid reliability and supports emergency power requirements.

Additionally, the project contributes to improving the operational efficiency of conventional thermal power plants by utilizing surplus electricity generated during non-peak periods for pumping operations.

Furthermore, energy requirement for Pumping water during day time may be harnessed from infirm Solar Power and stored in the form of storage water which in turn could meet the peak demand as per requirement.

The main structures involved in the project are two Rockfill dams (Upper and Lower Dam) with central clay core for upper reservoir (High water level: EL.516.00 m, Low water level: EL.494.00 m, Catchments Area: 9.50 Sq. Km) and lower reservoir (High water level: EL.337.00 m, Low water level: EL.300.00 m, Catchments Area: 9.25 Sq. Km) with a live storage of 13 million cum each, twin water conductor (7.70 ~ 7.30 m dia), an underground power house (157 m long, 22.5 m width, 48.7 m height) to accommodate four reversible pump turbines (vertical Francis, rated head 177m, maximum power discharge : 150 cum/sec/unit) of 225 MW each, an underground transformer cavern (119 m long, 17 m width, 17 m height) to accommodate four Main Transformers (three phase bank transformer. 16.5 kV / 400 kV) of 280 MVA each, an access tunnel (971.5 m long, 6.8 m width, 6.8 m height) to power house and 400 kV Gas Insulated Switchyard (GIS) linked through a cable tunnel (286.27 m long, 4.5 m width, 4.29 m height). Generation voltage is 16.5 kV.

Two 400 KV double circuit transmission lines connected with Durgapur and New PPSP 400 kV Sub stations.

Units of PPSP operates in Generation, Pumping and Synchronous Condenser modes of operation.

Total Generation achieved since commissioning till 31.03.2026 is 19961.99 Million Units. Its average Plant Efficiency is 77.69% which is higher than the Design value of 74%. Load Curve in post PPSP period also appears flattened.

• Highest Generation achieved in a Day (24 Hrs): 7.540 MU on 3rd February 2023.
• Highest Generation achieved in a Month: 202.5504 MU during January 2023.
• Highest Generation achieved in a Financial Year: 1578.0564 MU during FY 2022-23.

The Purulia Pumped Storage Project stands as a significant achievement in India’s power sector. Its successful and efficient operation demonstrates the importance of pumped storage systems in modern energy management, particularly in balancing demand fluctuations and supporting grid reliability.

Moreover, due to its engineering excellence and operational efficiency, PPSP has emerged as a model project, attracting engineers, researchers, and officials from across the country. It serves as a valuable platform for knowledge sharing, technical learning, and overall professional enrichment in the field of hydroelectric and energy management systems.