Have you received enough and clear information about the possibilities of
setting a power source driven by the Mighty River ?.
To be able to get some power out of the river you will need to know the
speed and the depth of the water where the runner is going to be located.
The size of the runner (propeller) is limited by the depth of the river and
of course some financial expenditures -- I am assuming here that the
mechanical to electrical conversion can be done by you.
5 miles/hour is about 2.24 meter/sec and a propeller type runner with one
square meter area has the potential of being able to extract a theoretical 5
KW from the river ( One square meter is about 10.76 square feet of runner
surface area). The efficiency of the system can be as low as 10%.
Also, there are other tricks to increase the water flow to give additional
power, these are things like a shroud to protect the runner blades, and to
increase the water flow by presenting a larger area mouth and an exit skirt
that is larger to use the water movement behind it to generate a "vacuum" to
pull more water through the blades, these things may increase the power more
River surface speed varies between the surface and the bottom of the river.
For this type of energy recovery a decision needs to be done and it is the
RPM of the runner (propeller) and the RPM of the generator . AQUAIR uses a
permanent magnet generator designed for low RPM and the Blades (runner) are
also set for high RPM - The blades in this case have a profile like the
blades for a boat gas motor.
You could EXPERIMENT using an electric Powered motor those used by fishermen
You need to remove the two blades propeller they use and replace it using a
much larger multi blades propeller -- I suggested this to a friend of mine
and he replaced the blades with a large, I believe, 5 blades propeller taken
from a electric fan unit. I know that he charges a 24 volts battery (I do
not recall the motor operating voltage), he has been boating in Europe and I
have not been able to contact him to get more information and a good
description of his finished project and the possible modifications he may
have done to the blades.
Most of the trawling motors are brush type, but I have been told the there
are one or two models that use semiconductor switching and those could be
used with rectifier diodes because they are true AC Motors without
brushes -- I do not have any idea where to get them or which are the ones
that are brushless motors -- MAYBE, since you are in the Big River area, you
may inquire about them and even give us the info.
The blade angle and the water velocity and, of course, the "load" will
determine the RPM of the generator.
Date: Mon, 24 Dec 2001 02:35:18 -0000
From: "loxley_72401" <loxley@...
Subject: Hi, everybody. I've got a question about floating water wheels.
I joined this group after I read the archives and saw a passing
reference to a water wheel made out of a 55 gallon drum that floats
in the water.
I am looking for a power source for my houseboat, you see, on the
Mississippi River, which flows around four or five miles an hour.
Most of the research I've done concerning hydro power has to do with
drops of water. Well, I've got no head to work with, but by golly
I've got flow! :)
I want to anchor, and let the river do work on a wheel (or series
thereof) of some sort, to provide me with AC or DC electricity. The
Aquair seemed rather expensive.
I am envisioning one or two or three 55 gallon drums with big paddles
on the sides, like a paddlewheel, floating in the water behind my
boat. Well, that's straightforward enough. Can I generate a realistic
amount of power this way? And what do I do to extract the electricity
out of the mechanical torque of the wheel(s)? Find an old generator
and attach the water wheel axle to where teh driveshaft of the motor
used to be?
I've looked all over the place already trying to figure all this out
on my own, with no luck. Can y'all provide me any insights that may