Find mass flow rate using heat differential

[mckray]

Homework Statement

An experimental power plant at the Natural Energy Laboratory of Hawaii generates electricity from the temperature gradient of the ocean. The surface and deep-water temperatures are 25°C and 7°C respectively.

The cold water that enters the plant leaves it at a temperature of 12°C What must be the flow rate of cold water through the system? Give your answer in kg/s & L/s.

dm/dt = ?

Homework Equations

W = Q_H - Q_C
e = 1 - T_C / T_H
c_water = 4190 J/kg*K

The Attempt at a Solution

I understand that it takes a certain amount of time to raise the water from 7°C to 12°C, but I don't know how to find that or how to relate it to a flow rate.

 

[Eagle's Wings]

remember what you have and what you want to know. you have ΔT, c, and P (which is Q/t) and you want kg/s (which is mass/time)...i think there is an equation for that, do you remember it? remember, your answer is going to be in kg/s.

 

[SteamKing]

How much electrical power is the plant supposed to generate? That would seem to be a critical bit of information in determining how much flow is required.