Runoff water as energy source?

[PJay_A]

I live in Florida, where it rains quite often. I was thinking if it might be possible to put all that runoff water to use and generate electricity from it by feeding the drains and gullies on the roof and the sides of the house to spin a turbine that would generate electricity. While I realize this would not provide even a fraction of a home's electricty, but at least I'm guessing it should be enough to contribute some what of a savings off the monthly electric bill!

What would I need to build this?

[a_lost_packet_]

Replying to:

I live in Florida, where it rains quite often. I was thinking if it might be possible to put all that runoff water to use and generate electricity from it by feeding the drains and gullies on the roof and the sides of the house to spin a turbine that would generate electricity. While I realize this would not provide even a fraction of a home's electricty, but at least I'm guessing it should be enough to contribute some what of a savings off the monthly electric bill!What would I need to build this? Posted by PJay_A

It takes a lot of water to generate power.  Just as important as having the water is the strength of the flow.  That's really the energy you're harnessing, after all.  If you could channel all the water which fell on your roof into one drain you might be able to power a small lightbulb.  But, what happens when it stops raining?  Would the money you invested in harnessing the water be well spent?  How long would it take to recoup those startup costs?  A year?  Two?

One thing you CAN do is use "brown water" to water your lawn and plants.  Brown water is simply runoff and collected, untreated water.  By using brown water, you can save a goodly amount of money if you're a gardener type and use water frequently.

Basically, the most common way to do this is to collect the runoff water from your roof by channeling it into a tank and then using either a gravity feed or a pump system to supply the water where you want it.  You'll find Brown Water systems at gardening stores.  Typically, they're nothing but a 55 gallon drum with a spigot in it.  It's cheaper if you just go find someone selling plastic 55gl drums (clean) and install your own system with valves, bulkheads and pvc pipes.  The savings to gardeners and those with water bills impacted by yard watering can be fairly significant.  Check with your local Agriculture/Extension service for regulations along with State EPA.

However, be advised, there are EPA regulations regarding the use of Brown Water Collection systems and may be local ordinances you have to follow.  Everyone is dependent on water and that runoff might be part of a supply of water others depend on.  So, it's usually got some regulations attached to it.  Standing water also breeds mosquitos so there may be regulations regarding catchment basins and Brown Water Collection tanks in your area as well.

For the money invested, a solar power collection/utilization system would be your best bet if you want to reduce bills using renewable energy available to you.

I put on my robe and wizard hat...

[neilsox]

I live in Jacksonville, Florida. It has been weeks since the last rain that sent 100 pounds of water own our one down spout which drains about 500 square feet of roof area. The usable drop is about 9 feet = 900 foot pounds. One horse power = 746 watts = 550 foot pounds per second. If your turbine was extremely efficient, output might be 746 watts, except it takes at least 100 seconds to get 10 gallons to the down spout. That would be 7.46 watts for a few minutes per month. I have to agree, pay back is perhaps 100 years, likely longer. Taller buildings and larger roof areas might be more practical. Drainage ditches in mountainous locations also have the possibility of harvesting some energy. Typically Florida is so flat, we use energy to pump drainage and sewer water.   Neil

[rtyuRTYU5678]

I was thinking.. since plants use chlorophyll "the pigment in plants that captures the light energy required for photosynthesis" to convert sunshine into usable energy has anyone tried to make solar cells using this and figuring some way to drain/use the converted energy directly?

[vogon13]

 

How about this:

 

A criticism  of wind turbines is the variability of prevailing wind conditions.  How about using each wind turbine (or wind farm) to electrolyze water (rain water if pure enough) into hydrogen for use in vehicles.  You would not be concerned about a still air evening if the business plan for your hydrogen facility is predicated on monthly/average wind conditions.

 

Also, for hydroelectric facilities in parched area, adding cogeneration in the form of a wind farm would conserve water otherwise released for power.  Again, you are playing the averages and during no wind conditions you do release water, but during wind you can release less water.  

 

For the hydrogen wind farm, during heat waves and electrical demand peaks, divert power to grid, resume hydrogen production after peak passes.

 

Collecting rain water/ condensation (dew) for electrolyzing might help water economy in parched areas.

 

 

TPTB went to Dallas and all I got was Plucked !!

So many people, so few recipes !!

Let's clean up this stinkhole !!

[Eskie]

Maybe install one of these on every river on the face of the earth, and the tides?

http://re-energy.ca/t-i_waterbuild-1.shtml