Opinion (Spotlight Weekly)

Devastation Of Upper Karnali Project

By AB Thapa

All of us know very well the terrible September eleven event that shook the whole world. The New York twin tower was blown up by Al Qaida. If it is asked why the twin tower was blown up, perhaps we might get a very simple answer. It could be an act of revenge. Now let us take a some what different case. Let us suppose the USA Government itself blew up the twin tower or let us suppose the Saudi Arabian Government bombed all her oil fields. How the news would have been received throughout the world, if the USA and the Saudi Arabian Governments had actually done so? Certainly, every sensible man would have definitely felt that the concerned decision makers must have gone mad. However, nobody would ever believe that such thing can really happen. Unfortunately our country is very soon going to be victimized for our similar unforgivable doing if some of our decision makers are not dissuaded in time from carrying out such act utterly harmful to our nation. We are soon going to devastate the 4180 MW mega Upper Karnali power project which might be one of the best projects even in the whole world to generate exceptionally cheap peaking hydroelectric power on an enormously large scale. There is a great demand for peaking electric power in India. Moreover the peaking electric power fetches much higher price. In 1991 the Thai Government was paying Laos Government US Cents 5.8 per KWh for peaking energy, whereas such price for the remaining hours was only about US Cents 2.98 per KWh. The electricity produced by the mega Upper Karnali storage project could be exported to India to the mutual advantage of both Nepal and India.

Exceptionally Favourable Topography

The Karnali river makes a big loop in its lower reach near a place called Asare. From here the river flows in the south-east direction for about 25 kilometers, after that the river makes a complete reversal in its direction. The river comes back to a point just two kilometers away from its earlier position near Asare. There is a drop of about 150 meters in Karnali river bed elevations between these two positions merely two kilometers away from one another. The project to utilize this bend for power generation was originally known as the Karnali Bend Project. Later on the name was changed to Upper Karnali Project.

Two Mutually Exclusive Upper Karnali Projects

The Karnali basin is the first to arouse keen interest in Nepal's vast hydropower development study. There are several attractive sites for the generation of cheap hydroelectric energy in this basin. In early 1960s an agreement was signed between HMG of Nepal and the UNDP for providing assistance to conduct a survey of the Karnali river and its main tributaries culminating in a pre-investment report indicating hydroelectric potential of the river as well as the best sites for hydropower development. The final feasibility reports and general basin development report were submitted in February, 1966.

In 1980s further studies of the two projects were carried out under the aegis of the World Bank. They are the feasibility study of the Karnali Dam Project (Chisapani) and the pre-feasibility study of the Upper Karnali Hydroelectric Project ( Karnali Bend Site). Unfortunately, the scope of the Upper Karnali Project study was deliberately made very narrow. The size of the project was scaled down to be suitable to meet the Nepal's internal power requirement completely disregarding its vast potential to generate exceptionally cheap peaking energy for export to India. Thus there are at present two Upper Karnali projects. They are the 300 MW Upper Karnali Project and the 4180 MW mega Upper Karnali Storage Project. These two projects are mutually exclusive. In other words, it would not be possible later on to build the 4180 MW mega Upper Karnali Project without sacrificing the small 300 MW small Upper Karnali Project. The relevant excerpt from the WORLD BANK supported Upper Karnali project study report is presented hereinafter.

World Bank’s Disapproval of Small Upper Karnali

The World Bank has disapproved of the small Upper Karnali project. The relevant excerpt from the World Bank supported Upper Karnali project study report is presented below.

“Even when assuming that the KR 1 A run-of-river project ( small 300 MW Upper Karnali project) is a sunk cost, it will be seen that a single large power plant (4180 MW) associated with the major storage project is less costly than the combined cost of smaller plant at the same location (3532 MW) and a second power plant at the foot of the storage dam ( 408 MW) discharging directly into the KR 1A run-of-river project head pond. Based on this assessment, it appears that the later development of the major hydro storage project at Site KR 1 ( mega Upper Karnali Project) would cause the KR 1A run-of-river project to be effectively discontinued. There may be limited opportunity for secondary energy generation during the periods of spillage”.

Demand for Peaking Power in India

At present India is experiencing an acute shortage of peaking energy. At the beginning of the Eight Plan, the total peaking shortage was 20% whereas the energy shortage was only 9% of the total power generation. The thermal and nuclear power stations are suitable to supply electricity to meet the base load demand of the system. It is not economic to use them to supply peaking energy. Gas turbines can be used to meet the peak load demand because of low specific investment costs and quick start up. However, the efficiency is limited due to the high exhaust gas temperature of the turbine.

India is making every effort to improve the hydrothermal mix for ensuring better system operating condition. However, the share of hydropower in the overall power generating capacity has steadily declined since the last few decades. The share of the hydropower in the overall power generating capacity was 50.6% in 1963. But few years before it has come down to only 25.66%.

Pumped Storage Schemes

Most of the good sites for the hydropower development have already been developed in the Northern India. There are even now several good sites for hydropower development in the North-Eastern India which have not as yet been used. However, such sites are at locations far away from the load centers. As a result, the Government of India in recent years had to embark on a plan to develop the pump storage schemes

Pumped storage schemes are provided for the generation of peaking power, even though there is a net energy loss in the system because more energy is consumed in pumping than can be produced by the turbines. The cycle efficiency of a pumped storage plant can usually be between 60 and 70 percent. It implies that such a plant consumes abut three units of electricity to produce only two units during the peak hours. The cost of the peaking energy produced by a pumped storage plant will have to take into account the investment to be made in the construction of the pumped storage plant. The per unit capacity investment cost of a pumped storage plant can be comparable to the cost of a similar hydropower located at a favorable site.

So far 56 major pumped storage schemes with a total installed capacity of 94,000 MW are reported to have been identified in India. Already few pumped storage schemes such as the Nagarjun Sagar (700 MW), Kadampani (400MW), Kadana (240MW), Panchit (40MW), Paithan, and Ujjani are either in operation or under various stages of construction. Bids were being evaluated some years ago by the West Bengal authorities for a civil work contract for the 900 MW pumped storage facilities at Purulia on the Ayodhya hills. Three other pumped storage facilities of similar capacity are being planned. The pumped storage at Sardar Sarovar (1200 MW) and Tehri (1000MW) are planned for construction in near future.

Rush to Grab small Upper Karnali Project

The concept of the small 300 MW Upper Karnali Project is very simple. It includes a small diversion dam to provide daily regulation, a spillway for the passage of excess water across the dam particularly during the floods, desanding facility, a power tunnel across the Bend, and a power house at the downstream side of the Bend. The small Upper Karnali project is a very attractive project by comparison with many other hydropower projects similar in size, as a result, recently some private developers were trying hard to acquire it. The proximity of the dam site from the power house helps to bring down the cost of the delivery tunnel and its related structures like the surge chambers although the construction of a low height diversion dam across a big river of the size of the Karnali flowing in a narrow gorge is not an advantage. Unfortunately this relatively small 300 MW project would preclude the 4180 MW mega Upper Karnali Storage project. It indeed is a matter of great concern. It might astonish many of us to learn that the per unit investment cost ( US Dollars/ KW ) of the 4180 MW mega Upper Karnali project would be far less than such cost of the 10800 MW Karnali Chisapani High Dam project. Thus this project could be the most attractive hydropower project for the export of peaking power to India in near future

Karnali Chisapani vs mega Upper Karnali

The Upper Karnali Storage project and the Karnali Chisapani Storage project would be having waterways quite comparable in length ( about 2 km), but the Upper Karnali project would be operating at a head almost two times greater than that of the project at Chisapani. It makes the Upper Karnali project far more attractive for export of cheap peaking power to India than the Chisapani project. Reasons for it are explained below.

Of all the site characteristics, head is the most important. Design guidelines, 1989 approved by the American Society of Civil Engineers has given some simple reasoning that would help to explain why the Upper Karnali project operating at a head about two times greater by comparison with the Chisapani hydropower could be built at far less per unit installed capacity cost. "Very simply if one doubles the head the quantity of water needed to produce a certain amount of energy is halved. Thus, for like site energy development the conduit area and reservoir volume are halved and further large cost reductions occur for powerhouse and machinery costs. This fundamental consideration is at the root of the large cost reductions that occur at higher heads." Needless to mention that the lower investment cost means the generation cost of the electricity would also be less.

The Stage A study report of the Karnali Chisapani Project shows that the increase in hydraulic head greatly helps to enhance the net project benefit. It has been explained in the report that the incremental benefit would be about six times greater than the incremental cost if the height of the Chisapani dam is further raised over the present height fixed at 270 meters. It is stated in the report that the dam height was limited at 270 meters for the reason that higher reservoir levels and dam heights would cause the abutments of the dam to spread into the Banghar Khola upstream and would severely constrain project development between the downstream toe of the dam and the preferred spillway plunge pool location downstream. It is not satisfactorily explained in the report why other sites further upstream suitable for much higher dams were not considered for the optimization study.

In Conclusion

The mega Upper Karnali project could play very big role in uplifting the poverty ridden economy of our country in very near future. Thus, we should refrain from doing anything that would harm this project.