# How to Calculate the Power Output of a Waterfall Generator

• pooface
In summary, the conversation discusses the calculation of the power output of a water wheel connected to an electric generator driven by a waterfall. The efficiency of the system is given as 22% and the necessary conversions from imperial to SI units are made. The final calculation results in a power output of 232.42 megawatts.
pooface

## Homework Statement

A waterfall is 85ft high, and 3000 cubic ft/sec flow over it driving a water wheel connected to an electric generator. If the overall efficiency is 22%, how many kilowatts does the generator develop?

## Homework Equations

density of water =1000kg/cubic meter
P.E. = mgh
weight=density*g*volume

## The Attempt at a Solution

Firstly convert to SI units.
85ft = 25.91m
3000 cubicft/sec = 914.4 cubic meter/sec

weight of the water being applied = (1000)(9.81)(914.4)
= 8.97 MN

P.E.=(8.97 MN)(25.91m)
=232.42 MJ
power in = 232.42 MJ /1sec = 232.42 megawatts

eff =0.22

0.22 = POUT/232.42 MW

Are my steps correct?

3000 cubicft/sec = 914.4 cubic meter/sec

I'm getting 3000 cubicft/sec = 84.95 cubic m/s

other than this, everything looks right to me. be sure to convert to kW when you finish...

how do you do a conversion such as 3000 cubic ft to cubic meter?

Yea, I realized i just did a ft-m conversion instead of cubic ft to cubic meter (a function on my calc).

pooface said:
how do you do a conversion such as 3000 cubic ft to cubic meter?

Yea, I realized i just did a ft-m conversion instead of cubic ft to cubic meter (a function on my calc).

I actually just used google.com. I typed in 3000 ft^3 and it automatically converted it.

But we can do it this way:

we know that 1 ft = 0.3048m

(1ft)^3 = (0.3048m)^3

so 1ft^3 = 0.0283168466 m^3

so 3000 ft^3 = 84.95 m^3

amazing...thanks a lot learningphysics. You are truly an asset to this board. I have another test this friday. Hope I do well.

pooface said:
amazing...thanks a lot learningphysics. You are truly an asset to this board. I have another test this friday. Hope I do well.

thanks so much. I appreciate it! good luck on your test! you'll do great!

## 1. What is waterfall power?

Waterfall power, also known as hydropower, is the energy generated by the movement of water. It is harnessed through the use of turbines, which convert the kinetic energy of falling water into mechanical energy that can be used to do work.

## 2. How does waterfall power work?

Waterfall power works by using the force of gravity to turn turbines, which are connected to generators. As water falls from a higher elevation, it gains kinetic energy, which is transferred to the turbines and causes them to rotate. This rotation produces electricity that can be used to power homes, businesses, and other facilities.

## 3. What are the advantages of using waterfall power?

One of the main advantages of waterfall power is that it is a renewable energy source, meaning it can be replenished naturally and will not run out. It also does not produce greenhouse gas emissions, making it a clean energy source. Additionally, hydropower plants can be built in various sizes, making it suitable for both large-scale and small-scale energy production.

## 4. What are the limitations of waterfall power?

One limitation of waterfall power is that it is highly dependent on the availability of water. This means that during droughts or dry seasons, the amount of energy that can be generated may be reduced. Hydropower plants can also have negative impacts on local ecosystems and wildlife if not properly managed. Additionally, the initial cost of building a hydropower plant can be high.

## 5. How is waterfall power used in the world?

Waterfall power is used in many countries around the world, with the largest producers being China, Canada, Brazil, and the United States. It is used to generate electricity for residential, commercial, and industrial purposes. Some countries also use hydropower for irrigation, flood control, and water supply management. In addition, some small-scale hydropower systems are used in rural areas to provide electricity to remote communities.

Replies
2
Views
2K
Replies
4
Views
2K
Replies
29
Views
4K
Replies
2
Views
21K
Replies
2
Views
6K
Replies
2
Views
2K
Replies
2
Views
2K
Replies
2
Views
2K
Replies
3
Views
3K
Replies
5
Views
3K