How stupid we Nepalese people, government and also the elected bodies would look like in the eyes  of the international community once they learn  that our government on the one hand is  desperately calling  international institutions  for  help to protect us from hazardous consequences of the global  warming  even  by holding  a  highly symbolic cabinet meeting  at a very high location “ KALAPATHAR” close to the Everest summit itself  in  Himalayan  mountain   to  draw the attention of the whole world, and ridiculously  on the other hand we are  now going to build just few kilometers  away  from the very place,  where the historic cabinet meeting  was held, on the site  identified based on past surveys to be highly vulnerable to disastrous glacier lakes outburst floods (GLOF)  consequent  upon the global warming the giant Upper Tamakosi hydropower project, which will  have  installed capacity  exceeding the total  installed capacities  of almost all existing hydropower plants  built so far in  Nepal-  Kaligandaki A, both Marshyangdi  hydropower plants  and both Kulekhani  hydropower plants  combined  together.


We  are     going  to take   the    horrendous  risk despite the fact  that the small-scaled  alternative of the NEA proposed project would have not only been safer from the GLOF but it  would also have been far more suitable to match against the nature of the present demand for power in our country.   The small-sized  alternative project could have been  implemented within a much shorter period  to provide quick relief  from the present acute  power shortage crisis,  and it would also be  producing  at almost one third of the investment by comparison  with that of the NEA proposed variant  even more energy during critical dry season periods if  the seepage losses are not discounted. 


Danger in Consequence of Global Warming

There are several rapidly growing glacier lakes near the project site in Tibet in consequence of the global warming.  The great  risk of glacier lakes outburst floods (GLOF) to high gated barrage  and other structures of the NEA proposed Upper Tama-Kosi project  should not be underestimated. We already have a bitter experience of the 1984 Digcho GLOF  when the Namche hydropower built on the upper reach of the Dudh-Kosi river was completely washed away. 


Let us not forget that the Kulekhani high dam was also on the verge of collapse just few years after the completion of its construction.  It has been described in an article recently published in the journal “SPOTLIGHT”.


The reconstruction cost could be too much if the barrage and intake structure of the NEA proposed Upper Tama-Kosi project would be seriously damaged by big GLOF. Power supply would be suspended for a very long time which would have terrible consequences for the economy of entire country.
The Mini Upper Tama-Kosi project would be  having only un-gated   weir across the river.  The GLOF would cause only limited damage to the weir.  The damage could be repaired within a short period  at a relatively  small cost.


Less Energy in Dry Season

It is reported that the flat reach of the  Tama-Kosi  river serving as the floor of the reservoir of the NEA proposed  hydropower  project  is made of 300 meters high porous fill materials  lying  over the original  river bed.  The fill materials had accumulated after  a big landside dammed the river. There is a great possibility of excessively large seepage  of water from the reservoir.  As a result of such seepage, there can be a significant reduction in electricity  generation in dry seasons. 
The mini Upper Tama-kosi project would not require the provision of a reservoir.  The question of energy losses resulting from the seepage  through the floor of the reservoir does not arise.


Hydropower Economics

Our electricity planners do not appear to take cognizance of the fact  that  the electricity  price   (as well as generation cost)  varies not only with the seasons but it also widely varies  even  within a very short period of just one day.  The cost  of  generation of  electricity for the supply of peaking demand in the evening  hours can  be usually about three times  more expensive than that of  the off-peak  hours.


Our country is reeling from  acute   shortage of electric power. Most of our industries are  on the verge of collapse. People are facing great hardship due to  long hours  of  load-shedding reaching up to 16 hours a day and it is expected to increase even further  in days ahead.  However, during  the wet season months  quite limited areas are affected by load-shedding lasting  only for a very short period in the evening. Even such limited disruption in supply of power might have been  to a  certain  extent the result of transmission lines congestion. It is  quite obvious  that the NEA is now facing acute shortage of base load energy  which could have been  produced at exceptionally low cost within a very short period.


Rationalization of Existing Projects

All the NEA owned hydropower projects,  like the Kali-Gandaki, both Trisuli, both Marshyangdi, both Kulekhani and others are  capable  to run at full capacity even during the dry season periods.  They  have  been built at enormous cost to supply electricity to meet the demand for peaking. Obviously,  the generation cost of such peaking energy is always very high. Unfortunately at present the full capacity  of these hydropower projects built  to generate high  valued  peaking  energy has  not been fully utilized during the critically important dry season periods.  They are now  operated to  produce   a  very large  proportion  of cheap energy to meet  the demand for base load.   Thus,  the  reservoirs, high barrages, turbines, generators, transmission lines and civil structures provided  to generate and transmit peaking energy have not been utilized to the full extent.


Too Uneconomic

A  fifty percent proportion of the base load and the peak load capacities of the power stations operating in a power grid  is normally considered to be optimum mix. It implies in our case that the overall firm generating capacity of our power grid should have already grown very high on top of the existing 450 MW firm capacity ( 400 MW peaking capacity  and  50 MW base load capacity)  in order to effectively use the additional peaking capacity of the NEA proposed 456 MW Upper Tama-Kosi project.   Thus, it would be too uneconomic under present circumstances  to implement  a hydropower project suitable to produce excessively large peaking power such as the 456 MW Upper Tama-Kosi project.


Conclusion

Considering  the nature of the present demand for electricity in our country and also the vulnerability of main project structures,  the installed capacity of the Upper Tama-Kosi Project must be limited to just over 100 MW based on 95% probable dry season river discharge by targeting  to generate mostly  the firm energy to meet the demand for the base load.  Even after such drastic reduction in installed capacity  the total generation of electric energy during the dry season period would still be equal or even exceeding the generation by the NEA proposed 456 MW project ( in case  the significant  proportion of  the dry season flow is lost  in seepage)  despite the fact that the cost of such mini- project would be only about one third.  As the demand for peaking energy grows in future  the installed capacity could be raised with ease by providing additional structures if it     is  found  after some years of operation  and  further observations  that the GLOF and the geology of reservoir site  would not pose serious threat to the safety of the project.