# Homework Help: Efficiency of nuclear powerplants

1. Jul 17, 2008

### maithie

guys. help me to explain this question..

The efficiency of nuclear powerplants used to produce electricity is about 40%. Under what condition this conversation efficiency could be increased to 100%? What difficulty might be encountered?

thank you guys!

Last edited by a moderator: Jul 17, 2008
2. Jul 17, 2008

### Barny

Re: thermodynamics?

Are you supposed to be moddeling the nuclear power plant as a heat engine?

If so a good place for you to start answering this question would be to read up on the Carnot cycle and the Carnot efficiency? You could then progress to discuss how a nuclear power plant differs from an ideal heat engine, there really is tons to discuss in that question.

3. Jul 17, 2008

### maithie

Re: thermodynamics?

huhuuhuh.. dunno what to do here.. im not good in physics..

4. Jul 17, 2008

### Barny

Re: thermodynamics?

Ah ok, so what level of physics are you at?

So are you happy with what the efficiency of a power plant is? How would you describe it?

Once you have this you can then consider how each stage of the power plant effects the efficiency.

5. Jul 17, 2008

### maithie

Re: thermodynamics?

i cant understand sir... :(

what should i answer to this question?

6. Jul 17, 2008

### maithie

Re: thermodynamics?

i think its about the second law of thermodynamics

7. Jul 18, 2008

### Andrew Mason

Re: thermodynamics?

Yes. The second law says that there is a maximum theoretical efficiency that a heat engine operating between two reservoirs at different temperatures can have. This is a heat engine that operates on a Carnot cycle (this is a cycle in which the system is constantly in a state of thermodynamic equilibrium, which is impossible to achieve in the real world although it can be approximated). This maximum efficiency is independent of the type of thermodynamic system. So it applies to nuclear power plants as well as steam engines.

Write out the formula for Carnot efficiency. Under what conditions could you get this to be 100%?

Once you see the formula you will be able to answer the question.

Use common sense to answer the rest of the question, once you get the above answer.

AM