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I'm new at this and have been reading a ton and have done some calculations that may or may not be worthwhile.
I'm in Northern Central Indiana (US) in a "2" zone according to the maps but using observations in my specific location I believe the avg wind speed here is 10mph (I get better wind due to the flat surrounding farm lands).
My Avg usage is 923kwh due to a business I run out of my house (computer and server hosting) and I've begun a program of decreasing my usage. But currently that is 220kwh/week and as far as batteries go that would be 5 amp hours/day.
Since I'm mechanically sound and can follow building instructions, I do not want to buy commercially but I do not have access to a welder.
My prospective tower location is approx 100ft from the location of my battery bank.
What I'm looking for is the feasibility of generating wind in my location and suggestions for the best design for my low wind location.
Another variable is that I do plan on separating the rest of the house from my computer shop electrically.
Thanks in Advance! (Back to my research)
Ric
MacGyver Guru Joined: 12/05/2009 Location: United StatesPosts: 1329
Posted: 12:39am 10 Oct 2009
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RicRock
For starters, direct current doesn't like to travel long distances. It loses amperage somehow (magic?) If you're wanting to build the electricity right at your windmill, it might be better to transmit it to the ground 100 feet away as alternating current, then change it to d.c. to charge your batteries. I don't do it that way, so maybe you'd better wait for some of the rest of the crew here to chime in.
I use a different approach in that my windmills pump air. Each one is built around a small diaphragm pump and when the mill spins, a cam pumps a little squirt of air into a common aggregate of pipes and a large receiver (tank). From there, I run the compressed air through little "air engines" (very similar to 'steam' engines), which in turn rotate the generator of my choosing.
Doing it this way allows me to "service" the generator, say -- without having to climb to break-neck heights, since the generator is inside my shop down on the ground.
Something else, I should tell you -- All my stuff is really, really small. I don't have much in the way of power requirements, so I've designed my system to operate in a limited manner. That's not to say it couldn't be increased in size to accommodate more; I just keep things small.
I'm in the process of posting pictures of my toys (having a bit of trouble with that!), but as soon as I've got something for "show & tell", I'll post it here on the 4m.
Welcome to the club; it's a great place to learn lots of interesting stuff.Nothing difficult is ever easy!
Perhaps better stated in the words of Morgan Freeman,
"Where there is no struggle, there is no progress!"
Copeville, Texas
GWatPE Senior Member Joined: 01/09/2006 Location: AustraliaPosts: 2127
Posted: 01:44am 10 Oct 2009
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Hi RicRock,
This is not true. AC is affected the same way as DC when passing through a resistance. For power transmission like in the grid, it is easier to use AC, as conversions to compensate for the transmission voltage drops is easier.
DC may cause corrosion problems with wiring if insulation is insufficient for the voltages used.
I think the Kiwi's have proved the case for DC. The most effective use of wire, is when the average current and the instantanous peak current through the wire is the same[well filtered DC]. With AC, this is not possible as the peak current will always be greater than the RMS average.
Gordon.become more energy aware
MacGyver Guru Joined: 12/05/2009 Location: United StatesPosts: 1329
Posted: 07:44am 10 Oct 2009
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RickRock:
Looks like I'm wrong about the DC; my bad. Go with GWatPE's information.
I was passing on information I had gleaned from another source, which is apparently in error. In the US, all the grid power is transmitted at high AC voltage and I was told it was because it lost less power over long transmission distances than if it were DC.
At least my comment about the 4m being a great place to learn was spot on! Nothing difficult is ever easy!
Perhaps better stated in the words of Morgan Freeman,
"Where there is no struggle, there is no progress!"
Copeville, Texas
davef Guru Joined: 14/05/2006 Location: New ZealandPosts: 499
Posted: 10:20am 10 Oct 2009
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DC is only used on an underwater cable system, between the two islands.
I understand there are some good technical reasons for it. Voltage breakdown in the cable is lower with DC and probably other good reasons.
Hi-voltage DC is more dangerous than similar AC voltage. I was told that you had 50-60 times a seconds to let go of the wire, whereas with DC you don't get any chances!
Tinker Guru Joined: 07/11/2007 Location: AustraliaPosts: 1904
Posted: 02:38pm 10 Oct 2009
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MacGyver, it appears you only got part of the "magic" from your "source".
Look at it this way, wire transmission losses are related to the current (Amps) capability of the wire.
Now, to transmit a lot of power you need either a lot of current at medium volts or a lot of volts at medium current since Watts = Volts x Amps.
Transformers only work on AC so you have to use that to boost the output voltage of the power source to get the lower current.
In relation to wind generators, they are mostly alternators that already produce AC voltages so that is relatively easily to transform to a higher voltage for a long wire link. As long as the frequency (RPM related) is not too high for the common 50Hz (or 60Hz) transformers, for higher frequencies a different transformer is required.
Of course, one then requires another transformer at the far end to lower the boosted voltage to a more practical value for rectifying and battery charging.
Notice. New forum software under development. It's going to miss a few functions and look a bit ugly for a while, but I'm working on it full time now as the old forum was too unstable. Couple days, all good. If you notice any issues, please contact me.
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