(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Pumped Energy Storage. A water reservoir has surface area A and depth D. The water flows down pipes and through turbines to generate electric power. The bottom of the reservoir is at height H above the turbines. The depth D of water in the reservoir decreases at a rate δ. (a) Calculate the total gravitational potential energy U. (b) Calculate the available power P = |dU/dt|, i.e., available for conversion to electric power.

DATA: A = 8 ×10^5 m2; D = 14 m; H = 102 m; δ = 0.55 m per hour; density = 1.0 ×10^3 kg/m3.

2. Relevant equations

U=mgh

P=U/T

3. The attempt at a solution

U=mgh

U=(density*area*depth)*g*h =1.1206E13 J

then 1.1206EJ/((1/3600)*.55)=7.3355E16 W

but thats not correct. whats wrong here

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# Pumped energy storage

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