3 Suppose 300m of elevation separate the upper and lower res

3. Suppose 300-m of elevation separate the upper and lower reservoirs of a pumped hydro system. Each has an average surface area of 10 hectares (100,000 m2) and their surfaces are allowed to vary in elevation by 1m.

If the penstock efficiency is 90% and the turbine/generator is 80%,

what is the average power that could be delivered over a 12-hour period?

Solution

Area of the reservoir immaterial, only height difference is used

Power = rho Q g H (Nm/s) = J/s = Watt. Multiply by time period in seconds or hors to get WH or KWH

derate by efficiencies .9*.8