Posted by harry on July 15, 2009, 6:48 pm
> Harry,
> >Well, you could use an automotive alternator for a wind turbine, in
> >fact it's not a bad idea, I have seen several. A cheap solution for a
> >DIY project.
> This idea that an automotive alternator has any value in the hands of
> the general public for a wind-turbine is just plain bogus. Wayne's
> statement "That requires a rotor >20' in diameter. Are you trying to
> say that you can hang that on a car alternator?" is a valid concept.
> The OtherPower people who are flown hundreds of hand built
> wind-turbines use 1000Lb. trailer axles to their home-built 10'
> wind-turbine and 6000Lb. trailer axles to their home-built 20'
> wind-turbine. If you try to hang even a 10' blades directly on an
> automotive alternator's shaft the centrifugal and gyroscopic forces
> would cause that alternator to self-destruct in a very short time.
> Wind gyrates all over the place and you need a blade shaft that is
> designed to handle these wild forces, alternators are designed for
> steady rotational forces only.
> Next you run into the issue of RPM, normal wind might generate 1000
> RPMs with prop designed for high RPM, automotive alternators require
> way more 1000 RPM to power with any efficiency. Now you could cure all
> this with a separate prop shaft, bearing, and then gearing the mess up
> for the alternator, but all that costs money and efficiency.
> Lastly, you have to look at net power output, an automotive alternator
> is draining the battery for field excitement as it's charging your
> battery. Gross (charging) output - field excitement = net output.
> Understanding automotive alternators is not near enough, someone also
> has to understand wind-turbines, if someone can get this idea to fly
> in wind and is willing to post data, I'll give them benefit of the
> doubt if their data holds and they're trying to sell this plan to
> others, but until then selling this idea is nothing more than scam
> designed to steal people's money.
> BTW, I'm hurt that wasn't voted "Most Ignorant" maybe this post will
> help?
> >But you're right, these crackpot(s) wouldn't be capable.
> When you're Right, you are Right.
> Curbie
It would not be valid to put the turbine assembly on the alternator
shaft as it would need to turn many time faster than the turbine. One
I saw was driven about 20:1 faster using two sets of toothed belts and
an idler shaft. The main problem was keeping the weather out. The
rest of it was just automotive battery. Simple. I remember the
turbine was about ten ft diameter, three blades. It was a propellor
from an aircraft. It had been condemed as it had been subjected to
shock load butwas fine for the turbine.
Big fin to turn it into wind.
Posted by wmbjkREMOVE on July 15, 2009, 10:57 pm
On Wed, 15 Jul 2009 11:48:31 -0700 (PDT), harry
>It would not be valid to put the turbine assembly on the alternator
>shaft as it would need to turn many time faster than the turbine.
Energyman/richardson claimed that he'd rewound his alternators to
allow slow-speed operation. That was about as likely as his claims of
5kw, which he later changed to 10kw! He has also claimed or implied
that furling, slip rings, PMA rotors, and tall towers are all
unnecessary. He's a crackpot, and his posts aren't deserving of any
serious discussion.
BTW, there used to be a bunch of different people selling modified
vehicle alternators for direct use as wind turbines on Ebay. For
whatever reason, there are very few now. I wouldn't be surprised if
Ebay got a ton of complaints about those things, and therefore dropped
energyman instantly when they received the first comment about his
looney product description. His product looked like a $0 rebuild, but
he was asking hundreds, and using weasel words like "you may need a
field controller". Sheesh.
> One
>I saw was driven about 20:1 faster using two sets of toothed belts and
>an idler shaft. The main problem was keeping the weather out. The
>rest of it was just automotive battery. Simple. I remember the
>turbine was about ten ft diameter, three blades. It was a propellor
>from an aircraft. It had been condemed as it had been subjected to
>shock load butwas fine for the turbine.
>Big fin to turn it into wind.
That could never have been very successful. An airplane prop is
entirely the wrong thing for the purpose. A 10' rotor has about 1000W
potential at 20mph
http://www.ndsu.nodak.edu/ndsu/klemen/Perfect_Turbine.htm , but
probably only a small fraction of that in the arrangement you
described. Which brings up a simple point about low-cost home-built
wind turbines: if you do everything right, and even if you spend a lot
of time experimenting and tweaking your one-off, it probably still
won't be quite as effective as a commercial offering of the same rotor
diameter. But some people have more time than money, and can therefore
justify the project, which should be encouraged. On the other hand we
have the energymans of the world, who believe that reality is
optional. They start out doing everything wrong and ignoring decades
of sound practice, which is guaranteed to produce a horribly
inefficient machine that's highly likely to self destruct. Which is
still fine for them, unless they try to market their crap....
Wayne
Posted by harry on July 16, 2009, 8:08 pm
On Jul 15, 11:57 pm, wmbjkREM...@citlink.net wrote:
> On Wed, 15 Jul 2009 11:48:31 -0700 (PDT), harry
> >It would not be valid to put the turbine assembly on the alternator
> >shaft as it would need to turn many time faster than the turbine.
> Energyman/richardson claimed that he'd rewound his alternators to
> allow slow-speed operation. That was about as likely as his claims of
> 5kw, which he later changed to 10kw! He has also claimed or implied
> that furling, slip rings, PMA rotors, and tall towers are all
> unnecessary. He's a crackpot, and his posts aren't deserving of any
> serious discussion.
> BTW, there used to be a bunch of different people selling modified
> vehicle alternators for direct use as wind turbines on Ebay. For
> whatever reason, there are very few now. I wouldn't be surprised if
> Ebay got a ton of complaints about those things, and therefore dropped
> energyman instantly when they received the first comment about his
> looney product description. His product looked like a $0 rebuild, but
> he was asking hundreds, and using weasel words like "you may need a
> field controller". Sheesh.
> > One
> >I saw was driven about 20:1 faster using two sets of toothed belts and
> >an idler shaft. The main problem was keeping the weather out. The
> >rest of it was just automotive battery. Simple. I remember the
> >turbine was about ten ft diameter, three blades. It was a propellor
> >from an aircraft. It had been condemed as it had been subjected to
> >shock load butwas fine for the turbine.
> >Big fin to turn it into wind.
> That could never have been very successful. An airplane prop is
> entirely the wrong thing for the purpose. A 10' rotor has about 1000W
> potential at 20mphhttp://www.ndsu.nodak.edu/ndsu/klemen/Perfect_Turbine.htm ,
but
> probably only a small fraction of that in the arrangement you
> described. Which brings up a simple point about low-cost home-built
> wind turbines: if you do everything right, and even if you spend a lot
> of time experimenting and tweaking your one-off, it probably still
> won't be quite as effective as a commercial offering of the same rotor
> diameter. But some people have more time than money, and can therefore
> justify the project, which should be encouraged. On the other hand we
> have the energymans of the world, who believe that reality is
> optional. They start out doing everything wrong and ignoring decades
> of sound practice, which is guaranteed to produce a horribly
> inefficient machine that's highly likely to self destruct. Which is
> still fine for them, unless they try to market their crap....
> Wayne
!000W is all you could expect from an automobile alternator anyway.
The airplane propellor he had for nothing, it saved lots of work and
balancing problems etc. Also there was no possiblity of damage through
over-speeding, the thing was rated at 2000rpm, it would never achieve
that in any wind. I never did see it function on a windy day. The
most I saw it put out was about 2-3 Amps (ie 24-36w)
There's lots of people out there like to mess about.
It's amazing how many of these wind turbines you see in locations
where there's virtually no wind!
I too don't believe it would be possible to rewind an automobile
alternator.
Posted by Curbie on July 16, 2009, 8:35 pm
On Jul 15, 6:57pm, wmbjkREM...@citlink.net wrote:
> On Wed, 15 Jul 2009 11:48:31 -0700 (PDT), harry
> >It would not be valid to put the turbine assembly on the alternator
> >shaft as it would need to turn many time faster than the turbine.
> Energyman/richardson claimed that he'd rewound his alternators to
> allow slow-speed operation. That was about as likely as his claims of
> 5kw, which he later changed to 10kw! He has also claimed or implied
> that furling, slip rings, PMA rotors, and tall towers are all
> unnecessary. He's a crackpot, and his posts aren't deserving of any
> serious discussion.
> BTW, there used to be a bunch of different people selling modified
> vehicle alternators for direct use as wind turbines on Ebay. For
> whatever reason, there are very few now. I wouldn't be surprised if
> Ebay got a ton of complaints about those things, and therefore dropped
> energyman instantly when they received the first comment about his
> looney product description. His product looked like a $0 rebuild, but
> he was asking hundreds, and using weasel words like "you may need a
> field controller". Sheesh.
> > One
> >I saw was driven about 20:1 faster using two sets of toothed belts and
> >an idler shaft. The main problem was keeping the weather out. The
> >rest of it was just automotive battery. Simple. I remember the
> >turbine was about ten ft diameter, three blades. It was a propellor
> >from an aircraft. It had been condemed as it had been subjected to
> >shock load butwas fine for the turbine.
> >Big fin to turn it into wind.
> That could never have been very successful. An airplane prop is
> entirely the wrong thing for the purpose. A 10' rotor has about 1000W
> potential at 20mphhttp://www.ndsu.nodak.edu/ndsu/klemen/Perfect_Turbine.htm , but
> probably only a small fraction of that in the arrangement you
> described. Which brings up a simple point about low-cost home-built
> wind turbines: if you do everything right, and even if you spend a lot
> of time experimenting and tweaking your one-off, it probably still
> won't be quite as effective as a commercial offering of the same rotor
> diameter. But some people have more time than money, and can therefore
> justify the project, which should be encouraged. On the other hand we
> have the energymans of the world, who believe that reality is
> optional. They start out doing everything wrong and ignoring decades
> of sound practice, which is guaranteed to produce a horribly
> inefficient machine that's highly likely to self destruct. Which is
> still fine for them, unless they try to market their crap....
> Wayne
Wayne,
I don't know if old enough to remember to energy crisis of the 70-80s
but this scam reminds me of the of the widely circulated myth that GM
was hiding 100MPG carburetor technology, which seems silly now because
of their bankruptcy, but back then spawned a whole bunch of scammers
claiming to have found the "secret" and where willing to sell it to
you.
There is a belief that people who fall for these scams "get what they
deserve", I share this belief as long people who can see and prove
that these claims are scams clearly point THAT out to those who don't
understand the issues involved.
Once the money incentive all that left is an "Angry Toll", does this
description ring a bell with anyone?
Good post.
Curbie
Posted by newsletters@gmail.com on July 22, 2009, 2:27 pm
"Discussion subject changed to "A few idiots in these groups believe
Wind Generator must have PMA (permanent magnet) Motor." by Curbie"
Now, THAT's funny. (Where's that italics option when I need it? LOL)
> >Well, you could use an automotive alternator for a wind turbine, in
> >fact it's not a bad idea, I have seen several. A cheap solution for a
> >DIY project.
> This idea that an automotive alternator has any value in the hands of
> the general public for a wind-turbine is just plain bogus. Wayne's
> statement "That requires a rotor >20' in diameter. Are you trying to
> say that you can hang that on a car alternator?" is a valid concept.
> The OtherPower people who are flown hundreds of hand built
> wind-turbines use 1000Lb. trailer axles to their home-built 10'
> wind-turbine and 6000Lb. trailer axles to their home-built 20'
> wind-turbine. If you try to hang even a 10' blades directly on an
> automotive alternator's shaft the centrifugal and gyroscopic forces
> would cause that alternator to self-destruct in a very short time.
> Wind gyrates all over the place and you need a blade shaft that is
> designed to handle these wild forces, alternators are designed for
> steady rotational forces only.
> Next you run into the issue of RPM, normal wind might generate 1000
> RPMs with prop designed for high RPM, automotive alternators require
> way more 1000 RPM to power with any efficiency. Now you could cure all
> this with a separate prop shaft, bearing, and then gearing the mess up
> for the alternator, but all that costs money and efficiency.
> Lastly, you have to look at net power output, an automotive alternator
> is draining the battery for field excitement as it's charging your
> battery. Gross (charging) output - field excitement = net output.
> Understanding automotive alternators is not near enough, someone also
> has to understand wind-turbines, if someone can get this idea to fly
> in wind and is willing to post data, I'll give them benefit of the
> doubt if their data holds and they're trying to sell this plan to
> others, but until then selling this idea is nothing more than scam
> designed to steal people's money.
> BTW, I'm hurt that wasn't voted "Most Ignorant" maybe this post will
> help?
> >But you're right, these crackpot(s) wouldn't be capable.
> When you're Right, you are Right.
> Curbie