Question

1. Estimate the annual average output of Grand Coulee Dam, in megawatts (MW). Research the annual average flow and the average heat. List your sources. Show all calculations.

Answer 1

Grand Coulee Dam is one of the largest power stations in the United States.

The following are the specifications of the dam

Hydraulic head, h = 116 m

Spillway capacity, V = 28317 m3 /s

Capacity factor, c = 36 % = 0.36

Mass of water flowing, m = density x volume = 1000 x 28317 = 2.8317 x 107 kg/s

Gain in kinetic energy on falling to turbine , Q = loss of potential energy, mgh

Q = 2.8317 x 107 x 9.8 x 116 = 3.22 x 1010 J/s

Energy output, E1 = 0.36 Q = 0.36 x 3.22 x 1010 = 11592 x 106 W = 11592 MW

Annual energy output, E = E1 x 365 x 24 x 3600 = 11592 x 106 x 365 x 24 x 3600

                                    E = 36.55 x 1016 J

Answer:

Power output = 11592 MW

Annual average energy output = 36.55 x 1016 J