Star has been awarded the exclusive right by the AJ&K Council to design, construct, own, operate, maintain and transfer back to the GOAJK, or any entity or body designated by the GOAJK, at the end of the concession period, a 147MW hydropower generating Complex near the Patrind Village in Muzaffarabad, Azad Jammu & Kashmir. The Company is the owner and developer of the Project and its registered office is located in Islamabad, Pakistan.
The Project will be developed on river Kunhar and will generate electricity based on run of the river design. The Project envisages construction of a Concrete Gravity Dam (CGD) weir on river Kunhar, upstream of Patrind village in order to divert flows from river Kunhar to river Jhelum.
The Project will have a capacity of 147MW with annual generation capacity of 632.6 GWh at an annual plant factor of 49.13%, based on the historical hydrology of the site. Electricity produced from the plant will be sold to NTDC in its capacity as the Central Power Purchase Authority.
The Project is located on the boundary of Azad Jammu & Kashmir (AJ&K) and Khyber Pakhtunkhwa near the city of Muzaffarabad at a distance of around 120 km from Pakistan’s capital Islamabad. The majority of the Project structures, including the powerhouse will be located within the teritory of AJ&K. However, some of the temporary and permanent components of the Project will be located within territorial limits of Khyber Pakhtunkhwa.
The Project area is distinctly spread across river Kunhar on one side and river Jhelum on the other. The Project envisages connection of both these sides through a tunnel.
The Project is accessed through Boi Road on right side of river Kunhar at a distance of approx. 12.3 km from Garhi Habibullah. The left bank of river Kunhar lies in AJ&K and can be accessed by a 3.1 km track leading from main road between Muzaffarabad and Garhi Habibullah. The left bank of river Jhelum is accessible from lower Chattar, Muzaffarabad while a new bridge is proposed to be constructed across river Jhelum to access the right bank at proposed powerhouse site .
Technical Details and Information
The plan of the Project is to divert the waters of river Kunhar through a left bank conveyance system of sand trap and tunnels to the banks of river Jhelum in the city of Muzaffarabad. The natural difference of elevation between river Kunhar and river Jhelum, along with a 26 meter crest level weir provides a gross head of 114.5 meters to set up a 147MW power project.
Major project components envisaged under the proposed scheme include a weir structure, within the Kunhar River bend. An intake structure is proposed slightly upstream of the weir, within the same river bend, leading to the headrace tunnel, through a dual-chamber sandtrap. The headrace tunnel passes through the Lohar Gali ridge towards the Jhelum River. It opens into an underground surge tank, at the start of a vertical pressure shaft connecting with a horizontal pressure tunnel (penstock), dividing into three manifolds conveying design discharges to a surface type Powerhouse located on the right bank of the Jhelum River.
The Patrind weir has been designed for a discharge of 2626 m3/s and has also been checked for safely passing flood of 4800 m3/s. The crest elevation is 757 masl which is approximately 26m high from the river bed. There will be four radial type crest gates each 13 m x 10 m in size. The weir will also accommodate a bridge having deck at elevation 769 masl. The weir is also equipped with three bottom outlets with 3 m diameter each.
The intake block is located on the left bank of Kunhar River just upstream of the Weir. Two intake gates are provided having dimensions of W12 m x H 9 m. Each of these gates & stoplogs are crane operated. The facility is also equipped with trashracks, the velocity through trashrack and gates will be 0.6 m/s and 1.5 m/s respectively assuming maximum plant discharge of 153.66 m3/s.
The sandtrap system is mainly composed of the sandtrap chambers and flushing culvert.
From the sandtraps a headrace tunnel of 7.0 m internal diameter will lead till the surge tank having a lenght of 2182 m.
Circular concrete lined underground surge tank of 16 m diameter is proposed at the start of vertical pressure shaft to control water hammer and speed rise.
A circular pressure shaft of 79.5 m high and 7.0 m diameter is proposed in hill mass on the right bank of Jhelum River. The pressure shaft falls up to El. 646.52 masl from where the horizontal pressure tunnel (penstock) starts. Length of pressure tunnel (penstock ) is 43.735 m. Three manifolds having length of 156 m will lead to the powerhouse.
A surface type powerhouse to accommodate three vertical Francis Turbine units, each of 50 MW capacity, is proposed on the right bank of Jhelum River, about 3.21 km downstream of its confluence with Neelum River. The powerhouse site is about 8.52 km upstream of the Kunhar – Jhelum confluence.
A conventional outdoor type switchyard is proposed to be constructed on the right bank of Jhelum River. The power from the Project will be evacuated through 132 KV transmission line.
© 2011 Star Hydro Power Limited