Some Toughts on Tipai M Azizur Rehman People are talking left right and center of Tipai. going round and round, beating about the bush. It seems Pinak never studied physics of water energy and river. In TV talks, no one talked the physics of falling water. Without physics, it is a matter of simple common sense for the keen observers..
Bellow is a simplifyed Model:
A kg of water on sea level/ surface is converted into vapor/cloud by absorbing certain amount of heat energy from the sun, then raises on to mountain gaining further height/energy, higher the height higher the energy. That means a kg on 10,000 Meter height has 1X10000 meter-kg energy or 10000 meter-kg energy.
What is energy?
It has potential to work
What is work? ( Work can Physically make and break or change the state of matter)
The product of Force and Distance ( in Kg-Meter or Foot -Pound unit ) is Work or Energy. If you lift 5lb to 20 feet level/height, you have done 5x20 or 100 ft-lb of work. the object now has 100 ft-lb energy. If allowed to fall it will smash( make/break matter) with 100 ft-lb of work.
If 1 Kg ( is force - gravitational i.e., the pull between the earth and the kg mass/object). 1 kg water at hight of 10,000 meter is being pulled by earth center at a pulling force of 1kg wight. When the water is at rest, we say it has potential energy of 10,000 kg-meter.
Now allow the water to fall through 10,000 meter, say to see level, free fall like rain/waterfall and sliding through mountain slop is different. Sliding will be opposed by frictional/ resisting force created by rocks, ice, trees, soil etc . Distance covered x 1 kg will be work done. What is this work? the movement of rocks and soil down ward is the work. Water velocity (rate of movement) will slow down as load being carried. On mountain slop the velocity is higher , the of load of boulders and pebbles are also bigger. and velocity slows down. At any point of journey total energy can be seen in two parts . height gives potential energy at rest position, velocity gives dynamic/moving energy.
At Tipai, say at 1000 meter height ,the moment you stop water, the previous velocity created by upper height (9,000) meter will come to zero. You have to break the velocity by dam that will resist the water velocity and its level will rise at dam reservoir. Now you put the water through turbine pipe with generator (to produce electricity) water will fall through reservoir level height to generator height, gaining some velocity. To create electricity (which is energy, that can work), water has to overcome turbine resistance and again loose velocity (moving energy). After the turbine again the water will gain velocity (much lesser) to carry load.
Pinak says they will not hold water back but release all after getting getting electricity. (that will transfer maximum part of energy of water)
Then what is the difference????
Say the water is running down from 10,000 meter and Tipai is at say 1,000 meter. If the dam is not there Sylhet rivers will get water with 9,000 meter height energy which will have huge velocity or dynamic energy to drive the rivers to the sea as doing now.
It the dam was there, then Sylhet rivers will be driven by 1,000 meter height level energy i.e, water will have only one tenth of the original energy to drive to the sea. Rivers will be silted and flatten the basin with increasing floods (in the Padma no flooding as such as water is withheld/diverted at Farakkha) creating many channels and changes in the basin. Pinak says they will release entire water. But at what energy or velocity level ????] Water at Tipai reservoir at 1,000 meter height and water on mountain 10,000 meter height level are not the same. Sylhet rivers are already aging/dying /flattening without the dam. So the difference is big. |
