MicroHydro from rain water

[ChrisR]

Hi,

I am brand new to this stuff, and would like to experiment.  I've been watching the amount of water that has fallen from my roof in the last few rainy days, and it has started me thinking.  Has anyone come up with any way to use rainwater falling on a roof to spin a turbine?  If I could get a reasonable amount of water falling 20' during a rain, this should be able to generate some power to charge a 12 volt battery, I think.

Hypothetically:

Roof area:  100 m^2

Head: 6 m

P = 9.81 * FlowRate (m^3/s) * Head

Rainfall

(mm/hour)    Power (watts)

4.             6.54
   
5.             8.175
   
6.             9.81
   
7.             11.445
   
8.             13.08
   
9.             14.715
   
10.             16.35
    
11.             17.985
    
12.             19.62
    
    

Ok, so you add in inefficiencies and this doesn't look even close to worthwhile.  Any thoughts?

Chris

[pyrocasto]

Basically I cant see it really worth while unless you want to charge a 12v battery with a warehouse with one water spicket.

[kell]

Some place in India gets 39 FEET of rain each year.  But I don't suppose you live there.

[pyrocasto]

well 39ft is quite a bit. Just roll out a bunch of tarps on a hillside and make a creek when it rains. ;-)

[Nando]

Come on !!

Be Practical.

Nando

[hvirtane]

I've been thinking about

the same idea many times.

I think that it is worth

of making, you only have

to make the water turbines

cheap enough to make it practical.

You might make it with battery

charging turbines?

-Hannu

 

[hobot]

You might want to browse the falling droplet static electricity

generation concepts in first few sites in this Google search.

http://www.google.com/custom?q=electricity+from+falling+water+drops&sa=Search&client=pub-637
9962124902668&forid=1&ie=ISO-8859-1&oe=ISO-8859-1&cof=GALT%3A%23008000%3BGL%3A1%3BDI
V%3A%23336699%3BVLC%3A663399%3BAH%3Acenter%3BBGC%3AFFFFFF%3BLBGC%3A336699%3BALC%3A0000FF%3BLC%3A0000
FF%3BT%3A000000%3BGFNT%3A0000FF%3BGIMP%3A0000FF%3BFORID%3A1%3B&hl=en

Maybe a big bag that fills till a latch overpowered and let fall to windup

a flywheel attached to usefful device, slightly counter weighted to return

and repeat in a long downpour.

hobot

[Norm]

  A more practical use for rainwater is to store

it and use it for washing clothes...(You will save

 on laundry detergent also)then save the

washwater and using it to flush the toilet

you could save about $30 a month on the water

bill as opposed to Saving about a $1 on your

electric bill.

               ( :>) Norm.