Punatsangchhu-I is the first Project of the 10,000 MW initiative taken by the Royal Government of Bhutan (RGoB) and the Government of India (GoI) in May 2008, for development by 2020. The Punatsangchhu-I Hydroelectric Project (1200 MW), a milestone in Indo-Bhutan relations, is presently the largest hydropower project undertaken in the Himalayan Kingdom of Bhutan by the RGoB and the GoI. The Project, an environment-friendly run-of-the-river scheme, is located on the left bank of the Punatsangchhu in Wangduephodrang Dzongkhag in Western Bhutan. The Project will utilize 357m fall available in about 11 km river course.
Agreement between the GoI and the RGoB for implementation of the Punatsangchhu-I Hydroelectric Project was signed on 28 July 2007 by H.E. Shri Pranab Mukherjee, Hon’ble Minister for External Affairs on behalf of the GoI and H.E. Lyonpo Khandu Wangchuk, Hon’ble Minister for Foreign Affairs on behalf of the RGoB. Punatsangchhu-I Hydroelectric Project Authority (PHPA), an autonomous body was set-up for implementation of the Project on 05 October 2007.
The project sanctioned at a cost of ₹/ Nu. 35.15billion excluding IDC on December 2006 price level with installed capacity of 1095 MW ( now revised to 1200 MW) is being funded by the GoI: 40% grant and 60% loan @ 10% interest p.a. repayable in 12 equated annual installments commencing one year after the mean date of commercial operation.
Salient Features of the Project are:
WAPCOS Ltd. (Ministry of Water Resources, Government of India) is the engineering design consultants to the Authority. The premier organizations of Government of India, e.g.Central Electricity Authority, Central Water Commission, Central Water & Power Research Station, Central Soil & Materials Research Station, Geological Survey of Indiaand Survey of India make their valuable expertise available to the Project through WAPCOS.
The concerned RGoB authorities had approved lease/acquisition of 673 acres of GRF land, 78 acres of private land (involving 116 land owners) and 6 acres of Institutional Land (2 institutions) till the end of April 2013 for the project construction.
MAIN CIVIL WORKS
The Main Civil Works of the Project have been divided into three packages:MC-1, MC-2 & MC-3
MC-II:Construction of Headrace Tunnel (HRT) from Adit-I &Adit-II. This was awarded to M/s Gammon India Ltd. at a contract sum of₹/Nu. 3.99 billion on 27 March 2009 with a completion time of 60 months.
MC-III:Construction of HeadraceTunnel (from Surge Shaft End), Surge Shaft, Butterfly Valve Chamber, Pressure Shafts, Power House and Tailrace Tunnel including associated Hydro-Mechanical (HM) works. This was awarded to M/s Hindustan Construction Company at a contract sum of ₹/Nu. 6.88 billion on 27 March 2009 with a completion time of 66 months.
MAIN ELECTRO-MECHANICAL (EM) WORKS
Generating Plant & Equipment: The first EM works contract of Generating Units and Associated Auxiliaries was awarded to M/s Bharat Heavy Electricals Limited, a GoI Undertaking (BHEL) at a cost of ₹/Nu.10.15 billion on 07 January 2010 with a completion period of 62 months.
The Turbine Model was constructed and tested successfully and 80% of the detailed designs have been developed. Work is progressing as per schedule.
Transformers: The second EM works contract of Generator Transformers, Reactors etc., was awarded to BHEL at a cost of ₹/Nu.1.32billion on 09February 2012 with a completion period of 48 months.
Gas Insulated Switchgear: The third EM works contract of 420kV Gas Insulated Switchgear was awarded to Hyosung Corporation, South Korea at a cost of ₹/Nu. 113.18 millionand USD 17.92 million on 09February 2012 with a completion period of 44 months.
400kV XLPE Cables: The fourth EM works contract of 400kV XLPE cables was awarded to Sudkabel, Germany at a cost of ₹/Nu. 23.87 millionand Euro 5.415 million on 04May 2011 with a completion period of 55 months.
The Authority has entrusted the execution of the 400kV transmission System to BPC, a RGoB Undertaking on ‘Deposit Work’ basis. POWERGRID is providing consultancy to the BPC.
BPC has awarded the contract of two 400kV Double Circuit Transmission Lines of 186km length to M/s JyotiStructures&Gammon (India) JV at a sum of ₹/Nu. 5.80 billionon 12 August 2010 with a completion period of 48 months.
CLEAN DEVELOPMENT MECHANISM (CDM)
M/s Senergy Global Ltd.-RITES Ltd. Consortium were appointed as Consultants for getting the PHEP-I registered as a CDM Project. Request for Registration of PHEP-I as CDM project was submitted to the United Nations Framework Convention on Climate Change (UNFCCC) by M/s BUREAU VERITAS Certification (India) the Designated Operational Entity (DOE) on 27.12.2012.
The Project is scheduled to be completed in eight years w.e.f 11 November 2008(zero date), viz. by 10th November 2016.
The 1200MW Punatsangchhu-I Hydroelectric Project is envisaged to generate 5.70 billion units in an average year.