River flow/velocity measurements

[riverpower]

Hi,

   I live on a flowing river (1/4 mile wide, probably 60 feet deep, but relatively slow flow) and I want to get some velocity measurements to see if I can generate enough electricity from it.  Doing rough surface estimates (throw something in the water and count how long it takes to travel a given distance) I see numbers ranging from 1 to 4 ft/sec.

   Does anyone know of an inexpensive flow meter I could buy/build/rent to make some semi-accurate velocity measurements.  I live on the east coast of the US.  I probably only need to take measurements for a week or so.

   Any help would be appreciated.

THanks,

Dave

[willib]

The US geological survey , USGS should have some data on your river..

google USGS

my suggestion.

[nanotech]

The only problem is the USGS data will be for the entire width of the river averaged.  I believe what the original poster is looking for is something small to be able to measure where the fastest portion of the river is in order to find the best location (from river's edge to the center) for a generator.

While your idea has merit for finding  the best portion of the river (upstream / downstream), it's not going to be all that good for what the oP needs, I think.....

Of course, I could be just talking crap again.  

(I'm good at that)

[veewee77]

One thing to keep in mind with a project of this type is that if it is not a private river, and if there are fishermen and others that use it, whatever you put into the river will likely have to be approved by someone, and it can't obstruct the navigation of the river.

JMHO -YMMV

Doug

[riverpower]

Hi,

  thanks for your comments.  Yes, this is a public river.  My hope is to put a generator on/under/around my dock or mooring.  I'd expect some permits would be required, but if it is under my dock, I could do some experiments first to see if it is worthwhile.  That is why I want to measure the flow around the dock.  I figure that if the flow is decent, it would be easy to run the power cabling up the ramp to the shore.  

   While I have your attention, I've struck out trying to find a turbine for this.  The closest I came was to get one reply from Thropton Energy in England, but they have not answered since (no pricing, availability).  So I may need to buy/build the blades for the prop.  I don't think my skills are up to a darrius or savonios turbine.  Anybody know where I could find some blades that could be used under water, say one to two feet long?  I think I'll need to ask on the wind power site for help here.

[nanotech]

I am no structural engineer or anything like it, but from every experience I've seen with extracting power from moving water it has involved a ducted fan.  Don't know whether that's much help or not.

[Tallwind82]

If you have a bicycle handy, preferably with agressive tread, you could get a $20 electronic bicycle speedometer (walmart) and mount the bicycle on the end of your dock with the tire about an inch into the water. That should give you a relatively accurate measurement of the speed of the river.

Hope this helps.

Robert G

[DBuller]

    Sorry, I do not know of any flow meter. But there is the old, throw something in and time its progression over a set distance.

    If you are looking to create power from a river, you should look at my site. it is http://www.WildWaterPower.com . I have been working on this problem for a while, plus I have links to all the "no head" technology out there.

 -Dennis