[GBlist] Alternatives

[Paul Clint <smithja@sisna.com>]

It is really sad to listen to people whine and complain instead of
looking for solutions. I came to the conclusion that neither the
government or the utilities are going to solve the problem, and so, if
it was going to be solved, it was up to me as much as anyone else.

First, I started looking for a way to build a cheap wind generator.
Within 6 months, I had a working windmill with a fan 8 feet in diameter
built from three 55 gallon drums and $50 in screws,
bearings and pipe fittings.It was beautiful. It would turn in a three
mph breeze and would withstand120mph wind. The fan weighed only 70 lbs.

But there was a problem. The windmill did not turn fast enough. If I
used a mechanical belt, gear or transmission to increase the speed to
drive an alternator, the power loss would be substantial which
I didn.t want. (This would also increase the cost of construction and
maintenance as well as limiting power production to a narrow range of
wind speed).

So I began experimenting with different methods of generating power by
attaching a conductor to the circumference of the windmill fan so that
it moved through the magnetic field of a stationary coil on the ground.
In one particular experiment, I had stopped the fan to make adjustments
to the coils position when I noticed that the conductor
was still producing power even though it was no longer moving.

After considerable effort, I was able to determine that the power being
generated from the stationary cable was caused by a field created by the
electret effect which had been induced into the cable's insulating cover
by one of my experiment's.

I have now succeeded in enhancing this electret field to the point where
a 400 foot length of coaxial cable strung out along a fence is
generating 1000 watts in a 3mph breeze. The power produced is
relatively insensitive to the speed of the wind, but is increased
dramitically by high humidity.

Experiments with this method of generating power are now being
concentrated on how to induce an electret field in large quantities of
cable.

The experiments with the windmill did not produce any other viable
results and so I changed tactics. I decided to try to find a way to use
readily available, cheap alternators instead of trying to
build something exotic.

The problem with a cheap automotive alternator is that it needs to turn
at 1200 rpm and is usually limited to less than 1 kw generating
capacity. Increasing it's capacity is easy, all you have to do is
increase the voltage to the field coils. If you raise it from the 12
volts of an automotive application to 110 volts, you can increase its
capacity to almost 10 kw. Another little trick is to change the
diode rectifying bridge to a set of transistors switches which will
increase the efficiency of converting the 3 phase power to DC by 30%
which would give you substantially more than 10 kw.

So, the only real problem now, is the make it generate power at lower
speed. If you look at the method the alternator uses to generate power,
it involves moving a conductor through a stationary
magnetic field. But it would work just as well if you could create a
changing or moving magnetic field in the presence of a stationary
conductor.

Once you reach this point in understanding how the alternator works, the
solution becomes obvious. All that is necessary is to substitute part of
the required speed of the alternator with a change in the magnetic
field. This can be done by energizing the field coils of the alternator
with pulses instead of direct current.Of course, the timing, frequency
and duration of the pulses is critical and you will need a computer to
control them, but since you can buy microprocessor chips for 40 cents,
this isn't a significant problem.

So, now I can generate power very cheaply, the next problem is to
condition it to a useful form and to store it in sufficient quantities
to make it dependable.

This is the point where I found out how expensive batteries are. For a
reasonable system for my own house, it was going to cost $5000.
(Choke...choke). And it wasn't any good to look for cheap batteries,
because they wouldn't last as long and would cost even more when they
had to be replaced.

Well, I'm the kind of person who has to be absolutely certain there
isn't an alternative before I'll spend $5000 on something like
batteries. So, I logged onto the internet and started searching.

It didn't take long to turn up some possibilities. There were some
impressive claims being made about several different devices called
desulfators, pulse chargers, scaler wave generators and other
monicurs which if true, would definitely be less expensive.

In substance, these devices were supposed to clean lead-sulfate from the
plates of lead-acid batteries to make them last longer and work better.
One claim even suggested that old auto and truck battery cores could be
rejuvenated, thus providing a source of free batteries. (That was the
claim that rang my bell).

So I brought several different kinds of these pulse chargers, collected
a 100 old batteries, and started testing. The results were, to put it
mildly, dissapointing. Out of 100 batteries, only 2 were rejuvenated to
an extent that made it worth the effort.

In spite of the disappointment, I took note of the fact that the two
batteries which were rejuvenated, were no longer ordinary batteries.
They could be completely discharged and then recharged at a rate far
beyond what batteries can normally stand. I applied 10 amps, then 20
amps, 50 amps and finally, I connected it to my welder
and turned it up to 100 amps and the battery just sat there and
swallowed it all without heating or boiling. And it could be discharged
just as fast.

The pulse charger was apparently doing something, at least in the two
batteries on which it would do anything. I was now determined  to find
out what was happening so I cut the end out of the two
batteries under the positive pole and replaced it with glass so I could
watch the batteries' plates and put an oscilloscope across the pulse
chargers leads and turned it on. With the pulse charger operating, I
could actually see the lead-sulfate on the batteries' plates dissolving
and the scope showed pulses of more than 100 amps being pushed through
the battery, so there really was something unusual happening.

But I still didn't understand why.

For a week, I called battery manufacturers asking questions and finally,
an engineer at Exide explained that all batteries have a resonance
frequency, a point where the electrical resistence of
the battery drops to almost zero. This allows very large pulses to pass
through the battery.

So, it was like a stopped clock that tells the right time twice a day. I

had accidentally found a combination of fixed frequency pulse charger
and battery whose frequencies matched closely enough to work.

Now that the mystery was solved, I went back to the shop and built a
pulse charger which uses a microprocessor to hunt for the batteries
resonant frequency and then pulse the battery. And it is incredible, the
effect it has on the old cores. Some of them will take pulses of more
than 300 amps and all of them rejuvenated.

So the bottom line is cheap energy and virtually free storage that is
available now.

Paul


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