Penstock installation completed at Upper Tamakoshi hydro projectNepal will have surplus electricity after the 456 MW plant comes into operation in February
The Upper Tamakoshi Hydropower Project achieved a major breakthrough on Sunday night with the successful installation of the penstock pipes, bringing cheer to a country that has long been grappling with power shortages.
The 456 MW project located in Dolakha district in north central Nepal will be its largest hydropower plant when it opens in February next year. The plant will put Nepal in the position of a power surplus country and allow energy export.
Project officials said that it took more than seven hours to install the 73 sections with a combined weight of 27 tonnes. These immense tubes carry water from the reservoir to the turbines to generate electricity, and fitting them is one of the most challenging tasks of the project’s hydro-mechanical component. With the successful installation of the penstock pipes, the project has achieved 98 percent physical progress.
The penstock pipes are made of steel and carry water under high pressure. They are a vital component of a hydroelectric facility that allows water to move to the turbine.
Ganesh Neupane, spokesperson for the project, said the project had aimed to start generating electricity by mid-November, but the deadline had to be pushed back due to the poor work executed by the hydro-mechanical contractor, Texamo Railway Engineering. The installation of the penstock pipes had been planned for 2015.
Construction work stopped for months because Texamo lacked the expertise to execute the difficult task of installing the penstock pipes. Subsequently, the project developer, Upper Tamakoshi Hydropower Limited, appointed another contractor to fit the high pressure steel penstock pipes when the Indian firm abandoned the project after completing more than 95 percent of the construction work.
As delays in the execution of the hydro-mechanical component threatened to push back the completion date of the project which was already running late, the project developer asked the Indian contractor to reassign the crucial task of installing the penstock pipes to Austrian firm Andritz Hydro.
In January, Upper Tamakoshi Hydropower Limited, Texamo and Andritz signed a tripartite agreement under which the Indian firm subcontracted the task of installing the penstock pipes to the Austrian company. Immediately after signing the pact, Andritz mobilised workers at the project site and construction work resumed.
Nepal Electricity Authority Managing Director Kulman Ghising reached the project site on Sunday to witness the engineering feat. “The delay has cost us. But with today’s breakthrough, we will now be able to switch on all the turbines by the end of the next fiscal year,” said Ghising. “Other work such as welding and concrete lining of the pipes in the shaft will be expedited now.”
The project which entered the construction phase in 2012 has encountered massive cost and time overruns. The project’s price tag has swelled to Rs49 billion, excluding interest on loans, from the initial cost estimate of Rs35 billion.
Interest payments on long-term loans alone have jumped from Rs6.7 billion in 2016 to Rs14.42 billion in two years. The annual interest rate has been set at 11 percent. As of date, the total project cost including interest on loans has been estimated at Rs73 billion.