KURICHHU HYDROPOWER PLANT

Background

 The Kurichhu Hydropower Plant is located at Gyelpozhing, Mongar on the Kurichhu River in Eastern Bhutan. It is a run-of-river scheme, with a dam of height 55m (from its deepest foundation), crest length of 285 m and a surface power house located at the toe of the dam. The Project has an installed capacity of 60 MW consisting of four units of 15 MW each and a mean annual energy generation capacity of 400 million units (MU). The Kaplan turbine operates with a net head of 32 m and discharge of 53m3/sec per unit. A unique feature of the project is the fish ladder for migration of fish.

 The Kurichhu Project Authority was established to control and monitor the construction work, and to arrange funds for the construction. The Authority entered into an agreement with the National Hydroelectric Power Corporation Ltd., (NHPC) a Government of India agency, for the turnkey execution of the project. The Authority appointed Water and Power Consultancy Services (WAPCOS) as review Consultants. The construction activities started in 1995 with the diversion tunnel works.

 NHPC separately entered into a contract agreements with M/s. Asian Techs Ltd. for the construction of the diversion tunnel, with M/s. Hindustan Construction Company for the construction of dam, with M/s. Gammon India Ltd. for the construction of power house, with M/s. Bharat Heavy Electricals Ltd. for the supply and erection of electro-mechanical equipment, and with M/s. Om Metals and Minerals Limited for the supply and erection of hydro-mechanical equipment, and with M/s. Prem Power Construction Ltd. for the construction of 132 kV transmission lines. A host of other smaller Indian and Bhutanese firms also participated in the construction of the Project.

 The first 15 MW machine was spun on 13th April 2001. This first unit was synchronized to the Indian North Eastern grid on 13th August 2001, followed by the second unit on 15th August 2001, and the third unit on 27th September 2001. Commercial operation started from 1st November 2001. The fourth Unit was commissioned on 31st May 2002.

The Kurichhu Hydropower Plant was formally inaugurated by HRH Trongsa Penlop Jigme Khesar Namgyel Wangchuck and H.E Shri Sudhir Vyas, Ambassador of India to Bhutan on 26th April 2006.

Project Finance

In February 1994, the Government of India and the Royal Government of Bhutan entered into Agreement to construct the project wherein the Government of India agreed to finance the Project in the ratio of 60% grant and 40% loan repayable over a period of 12 years at a simple interest rate of 10.75%. The final cost of the Project on completion, including 68 km of 132 kV transmission line from Gyelpozhing to Nanglam, was Nu. 5,600 million excluding interest accrued during construction. The Royal Government of Bhutan further funded Nu. 40 million towards acquisition of land, providing communication network, and other infrastructure not covered under the scope of the Project.

 The repayment of loan component amounting to Nu. 2240 million to the Government of India started in July 2004, the interest accrued during construction amounted to Nu.1,035.529 million. So far Nu. 746.667 million of the loan amount was paid and a total of Nu.1.553 billion was paid including principal and interest at the rate of 10.75% per annum.

The transmission system of KHP was handed over to BPCL on December 31, 2003 along with all the assets, inventories, and associated manpower with a total assets value Nu. 641,494,889.26.

Salient Features of Kurichhu Hydropower Plant (4 x 15 MW)

Dam/Reservoir

Hydrology

Spillway 

Fish Ladder

 Power House

Power Intake and Penstock

Tail Race System  

Switch Yard

Transmission Line

Shunt Reactor

Operational and Financial Performance

During the peak power generation season, over 60% of the power generated from the Plant is being exported to India. The Kurichhu Hydropower Plant is providing power supply to eight Dzongkhags in eastern and central Bhutan. The drastic increase in the domestic consumption since February 2007 was mainly due to the commissioning of Ferro-Silicon factory at Motanga/Rabtenling Industrial estate at Samdrupjongkhar. The performance of KHP in generation, export to India, and sale to BPC for the last three years is shown in figure below :

KHP is still faced with frequent outages of single transmission line which restricts the full generation during the peak season. Over the years the performance of KHP had improved significantly while in 2008, KHP had achieved highest generation so far.  With ever expanding rural electrification and with urban and industrial growth the domestic consumption is increasing rapidly, resulting in revenue decreases.

 It may be noted that the most recent revision of KHP export power tariff was negotiated between the two governments of India and Bhutan on 12/12/2007 where in the export power tariff was revised from Rs. 1.75 per Unit to Rs. 1.80 per Unit with effect from 1st January 2008. It was also agreed that henceforth the KHP export tariff will be pegged to THP export tariff and whenever there is a revision in the power tariff of the later, the KHP export tariff will also automatically stand revised.

 Manpower

KHP Organogram