Of course your right. I guess what I'm after is just a little hands on experience. A small test wheel to get a feel for what power is in the water. My estimate is that I have about 20 to 30 feet of head from the top of my 1 1/2 acre lot to the bottom. To make the most of this I would have to divert water from the top corner of my lot right where there just happens to be a very scenic waterfall (upstream from the one in the video). The creek bed is solid smooth rock, no sand, no stones to hide a pipe and if I was in my neighbors shoes I would not want to see a pipe in that area.

     If I do divert to a pipe I suppose the best turbine would be a pelton (high head/ low flow)

     Of the types of wheels recommended I wonder what would be best if you discount head (indirectly since the pressure would not be built up in a pipe) and instead figure for a very fast moving small stream. Guessing, I would say the stream is between 60 to 70 gallons per Minute (or 1+ gallon per second) But it slides down fairly smooth rock at an angle that gives it a lot of speed. I think I might do ok with a cross flow type wheel setup at a natural ledge with a natural looking funnel of rocks of logs squeezing the flow into an area about 1 foot wide. Looking down the creek / falls from upstream the wheel could be completely hidden behind a ledge.

     At this time, our lot is undeveloped save for the septic drain field. I have the opportunity to design our cabin to be off or nearly off grid if I combine hydro with solar and conservation. I suppose under 100 watts can go a long way when it is 24/7 and combined with solar.

     We'll be up there again next month and I plan to build a small test cross flow wheel, quick and not too fancy just plywood and PVC.

     Oh, I almost forgot. Another question,
In researching the forum I saw where Flux wrote to another poster;

""I assume you have looked at matching the alternator to the wheel, if you have too little open circuit volts or too much resistance you may not be fully loading the wheel. Have you checked the power direct into lamps, which you can keep adding until you slow the wheel to where water spills over the buckets.""

     I'm curious to know more about alternator cut in when attached to a water wheel charging batteries. Seems like a whole different set of rules from wind turbines. Would things like tip speed ratio and stall apply? Or are the only 2 parameters - the ability for the wheel to startup and when the water flow exceeds what can be used? If the latter then can the coils be would with a high number of turns for low rpm charging or would this be a disadvantage same as too low a cut in on a wind turbine?

Here's some more pics of the 5-gallon bucket "Pico-Hydro":

http://www.flickr.com/photos/aidg/page5/

The generator "appears" to be a car alternator that is converted to a PMA. By using it to charge cell-phones, I'm guessing "it must" be making over 9-volts.

I made one out of a 55 gal olive barrel, but the same basic idea.

http://www.homebrewhydro.com/

     I know that just up the mountain there are several springs that feed this creek and my comment was only to say that not knowing all the source of the stream I suppose the regular steady flow is due to being spring fed.