# Heat engines

1. Oct 9, 2004

### gregbellows

Hi, I am stuck on the question, I don't require the solution, just how to get started.

A power plant's electrical output is 750MW. Cooling water at 15oC flows through the plant at 2.8x10^4 litres/sec and its temperature by 8.5oC. Assuming the plants only energy loss is to the cooling water and that the cooling water is effectively the low temperature reservoir, determine:

1. the rate of energy extraction from the fuel
2. the plant's efficiency.

Cheers
Greg

2. Oct 10, 2004

### Clausius2

What do you mean?. IF you're meaning $$\Delta T=8.5ºC$$ is the increasing of temperature of that water, then:

Power extracted of the fuel: $$W=W_{electric}+W_{losses}$$

The losses to the environment can be calculated:

$$W_{losses}=\rho Q c\Delta T$$

as a function of the volumetric flux Q, density and heat capacity.