Is generating electricity from rain water efficient?

In summary, if you have a roof that collects rainwater, a small hydro system can generate enough power to power your house.
  • #1
DWT
20
4
From small generators attached to the gutters of your house to large ones in the storm sewers, is it efficient enough to make the effort?
 
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  • #2
This only depends on the available amount of rain. If you build a Hoover dam or dig the Niagara falls ...
 
  • #3
huuvvo1444359776414.jpg


Sure. If you can do it with a faucet, you can do it with a downspout. The faucet powered light in the picture costs only $5.

But if you mean generate enough power to supply your house, no.
 
  • #4
Hydroelectric is just rainwater electricity on a larger scale. Rivers naturally collect rainwater from large areas.
 
  • #5
I think the rain gutter generators would be useful for "off the grid" households. Solar and wind are already popular I thought why not rain gutter/grey water pipe generators.
I have had this idea for a decade or so thought it was time to share it.
 
  • #6
DWT said:
From small generators attached to the gutters of your house to large ones in the storm sewers, is it efficient enough to make the effort?

http://www.renewablesfirst.co.uk/hy...-power-could-i-generate-from-a-hydro-turbine/

For a typical small hydro system the turbine efficiency would be 85%, drive efficiency 95% and generator efficiency 93%, so the overall system efficiency would be: 0.85 x 0.95 x 0.93 = 0.751 i.e. 75.1%


Is 75% efficient good enough?
 
  • #7
CWatters said:
Is 75% efficient good enough?
Is that the right measure of "efficiency"?

Say that you have 1 meter of rain per year on your 10 meter by 10 meter footprint for a total of 100 cubic meters = 100,000 kg of water. Say your eaves are 10 meters above ground for a total of one million kilogram-meters of lift. Gravity is 10 meters per second^2 so that's about 10 million Joules.

One kilowatt hour is 3.6 million Joules and costs about a dime.

That means that a year's worth of rainwater on your rooftop generates about 30 cents worth of electricity.
 
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  • #8
DWT said:
I think the rain gutter generators would be useful for "off the grid" households. Solar and wind are already popular I thought why not rain gutter/grey water pipe generators.
I have had this idea for a decade or so thought it was time to share it.
It's awesome to have ideas, but as jb Riggs showed, you can quickly do some basic calculations to see if they might be viable...to get them out of your head and at least on to the back of a napkin. We can help!
 

1. Is generating electricity from rain water a viable source of energy?

Yes, generating electricity from rain water can be a viable source of energy. Rain water can be used to power hydroelectric generators, which can generate electricity on a large scale.

2. How efficient is generating electricity from rain water?

The efficiency of generating electricity from rain water depends on the method used. Hydroelectric generators have an efficiency of around 90%, making them a highly efficient way of generating electricity from rain water.

3. What are the environmental benefits of generating electricity from rain water?

Generating electricity from rain water has several environmental benefits. It is a renewable source of energy, meaning it does not deplete the Earth's resources. It also does not produce harmful emissions, making it a clean source of energy.

4. What are the limitations of generating electricity from rain water?

One limitation of generating electricity from rain water is that it requires a large amount of rain to be effective. This means it may not be a viable option in areas with low rainfall. Additionally, hydroelectric generators can be expensive to build and maintain.

5. How does generating electricity from rain water impact the water cycle?

Generating electricity from rain water does not significantly impact the water cycle. The water used in hydroelectric generators is usually returned to its natural source, such as a river or lake, after use. However, large-scale hydroelectric projects can alter the natural flow of water and impact the surrounding ecosystem.

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