Page 276 - Handbook of Energy Engineering Calculations
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FIGURE 3 (a) Rising tail-water level in small hydro projects can
seriously curtail potential. (b) Anderson-cottonwood dam head dwindles
after a peak at low flow. (c) Low heads drive DOE estimates up. (d)
Linear regression curves represent DOE estimates of costs of small sites.
(Power.)
The actual power output from a hydro station is P = HQwe/550, where P =
3
horsepower output; H = head across turbine, ft; Q = water flow rate, ft /s; w =
3
weight of water, lb/ft ; e = turbine efficiency. Substituting in this equation for
3
the plant shown in Fig. 3b, for flow rates of 500 and 1500 m /s, we see that a
tripling of the water flow rate increases the power output by only 38.7
