Hydroelectric This is the list of major hydroelectric power plants in Andhra Pradesh.
Pumped storage hydroelectricity projects Pumped hydroelectric energy storage (PHES) projects with high water head are the cheap means of converting intermittent renewable power generation sources like solar PV or wind power in to base load supply for round the clock needs throughout the year. AP state is endowed with vast PHES potential adequate to utilise its vast solar PV power generation potential (above 1,000,000 MW installed on 16,000 km2 marginal lands) to meet ultimate green
energy requirements of its peak population (60 million). AP is considering on a major scale to install PHES projects to make available the surplus wind and solar power during the peak load hours. PHESs also generate income, in addition to
hydroelectricity cess/royalty, to the state in the form of water use charges at commercial rates for the evaporation loss or consumptive water from the reservoirs. The area occupied by the high head PHES is less than the area occupied by the equivalent
battery energy storage system (BESS) housed in a three storied building. High head PHES installation cost (2) of the grid which contributes to a stable grid to
ride through the power disturbances when power generation in the grid is dominated by the static solar PV power. Variable speed PHES plants also deliver the
power grid ancillary services. In high head PHES, unlined pressure tunnels/shafts are constructed to the extent feasible for reducing construction cost. The water reservoir of a PHES is created by building
embankment dams wherever required up to the required height and length. The rock required for building the dams is excavated from the reservoir area. Cheaper
drilling and blasting method is extensively used deploying state of the art
earth moving equipment because huge quantity of rock excavation is required for the construction of the rock-fill dams.
Polavaram right bank PHES: A 103,000
MW PHES project is under investigation with an upper reservoir, located near Parantapalle hamlet in
West Godavari district, with 90
tmcft live storage at 700 m
msl full reservoir level (FRL). The turkey-nest type upper reservoir is 18 km long from north to south and 1.1 km wide and its water surface area is 16 km2 with 200 m water depth and nearly 90 tmcft live storage. The adjacent
Polavaram reservoir at FRL 45 m msl with 194 tmcft gross storage is the lower reservoir as perennial water source. The average water head available is 600 m with a provision to draw 33 tmcft/day from the Polavaram reservoir by the PHES units located in semi open or underground power houses. To run the PHES on daily basis, the lower reservoir is to be kept empty by 33 tmcft below its FRL for holding the water released by PHES in generation mode. Another 33 tmcft is used to compensate the loss of storage capacity in the lower reservoir. This buffer storage is released in to lower reservoir for irrigation, etc. needs once in a year at the end of monsoon year and it is replenished at the earliest from the flood water inflows into the lower reservoir. Also seepage and evaporation losses from the upper reservoir are met from the buffer storage sourced from flood waters and not drawn from the lower reservoir storage. The excess buffer storage maintained in this upper reservoir can also serve up to 24 tmcft for other PHESs in the state which are using Godavari basin water and have no buffer storage of their own (ex: Jalaput PHES). The upper reservoir can be further expanded by 3.5 km length on its south side to enhance the live / buffer storage substantially. The PHES project can produce 412 billion
KWh at 4000 hours/year or 12 hours/day operation in generation mode by consuming the surplus power generated from the solar and wind power plants during the day time. This PHES can also moderate the severe floods by utilizing empty volume kept in the lower reservoir or operating in pump mode (maximum 7.63 lakh
cusecs) to fill the upper reservoir. In case of emergency / repairs, the entire water storage in the upper reservoir can be emptied safely into the lower reservoir / river within 24 hours by running the PHES in generation mode.
Srisailam right bank PHES: A 77,000 MW PHES project is feasible with an upper reservoir, located on the right bank side within 1000 m distance of
Srisailam reservoir, with 87 tmcft live storage at 650 m msl FRL. The reservoir bunds are constructed on 500 m msl contour line by 155 m high and the water surface area of the upper reservoir is nearly 20 km2. The adjacent Srisailam reservoir at FRL 270 m msl with 185 tmcft live storage is the lower reservoir with perennial water source. The average water head available is 340 m with provision to draw water from the Srisailam reservoir by the PHES units located in semi open or underground power houses. The PHES project can produce 308 billion KWh at 4000 hours/year or 12 hours/day operation in generation mode. Only 43.5 tmcft (50%) reservoir storage is used for power generation on daily basis and the remaining half kept as buffer storage to compensate the loss of storage in downstream reservoir due to PHES by releasing water once in a year in to the Srisailam reservoir to meet irrigation water requirements. The buffer storage is replenished later at the earliest during the monsoon/floods. This PHES can also moderate the severe floods by utilizing empty volume kept in the lower reservoir or operating in pump mode (maximum 10 lakh cusecs) to fill the upper reservoir.
Feasible PHES projects Notes: Power potential (MW) is in generation mode, MDDL→ Minimum Draw Down Level or lowest bed level of the reservoir, FRL→ Full Reservoir Level, m msl→ meters above mean sea level. The total water storage includes nearly 432 tmcft of irrigation components. PHES water storage is 793 tmcft only. The PHES land requirement is nearly 1% of the land required (41,250 km2) for equivalent
electricity generation by Solar PV power plants. The state has total installed solar power capacity of 4,116.01 MW as of 30 June 2021. The state is planning to add 10,050 MW solar power capacity to provide power supply to farming sector during the day time. Out of 10,050 MW, 6,400 MW capacity at 10 sites were offered for bidding. The winning tariffs are Rs 2.50 per unit which are at least 25% more than the earlier awarded tariffs of Rs 2 per unit in November 2020 even after reducing scope of work (no HV transmission line construction outside the solar park), state providing the land on lease, giving state guarantee for the timely payment for the power sold, allowing the state guarantee as security to get financial assistance at lower interest rates, disregarding higher solar power potential at these sites compared to Western and northern regions, etc. The AP high court has stayed the award of contracts to the successful bidders on the grounds that these contracts are excluded from the jurisdiction of APERC in contravention of the electricity act, 2003. The state has offered five Ultra Mega Solar Power Projects with a total capacity of 12,200 MW to developers under renewable power export policy outside the state.
Wind power The state has total installed wind power capacity of 4,083.57 MW as on 30 June 2021. == Other utility power plants ==