# Finding the energy balance of a hydroelectric power generator

1. Aug 10, 2012

### bgizzle

finding the "energy balance" of a hydroelectric power generator

I proposed a new hydroelectric energy idea to somebody and they asked me for a "energy balance". I know nothing about physics or anything relevant to calculating something like this. If somebody asked you for the energy balance of a dam, how would you go about finding that? Would you know exactly what they meant by energy balance, if not, what would you ask to get them to clarify?

so far I see equations relating to thermodynamics but I'm not sure why you would want to calculate the thermodynamics of dam. Just a reminder, I am ignorant so simplistic and very descriptive wording is appreciated.

2. Aug 10, 2012

### Staff: Mentor

Re: finding the "energy balance" of a hydroelectric power generator

Welcome to PF!

Another way of saying "energy balance" would be to do a "conservation of energy analysis". The point is to calculate all of the energy inputs and outputs and make sure they are equal to each other. This is the standard approach to a great many thermodynamics problems.

At a simplistic level, it starts with the gravitational potential energy of the water; weight density times height of the dam. Then multiply by flow rate to get power. Multiply by the turbine and generator efficiencies and it should equal electric power output.

3. Aug 10, 2012

### bgizzle

Re: finding the "energy balance" of a hydroelectric power generator

ok, thank you very much.

Do you know of any website that describe the process in detail for a dam?