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Forum Index : Windmills : newbee stupid observations and questions

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chaddy

Newbie

Joined: 08/11/2007
Location: Australia
Posts: 3
Posted: 11:55pm 07 Nov 2007
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Hi all
my name is Brett and i am from Adelaide,
I am a motor mechanic / Race car Builder and have been for over 20 years
i have been comming on this site for quite a while now and have a few questions and observations
having no formal degree's or anything i like to find out things for myself

1)Generator size and type,
After looking on ebay you can buy a 5kw - 10 kw diesel generator with perment magnet for under $2000 why can't this be converted or used for a wind generator

the F & P setup looks ok but at only 0.2kwh it seems like it would take a lot of them to keep a house hold running unless you lived in a cave and used one eletrical appliance at a time

i am a gizmo / tech freak and love having all the new toys and consiquintly we use a lot of power at home approx 40 - 50 kw a day, so i am looking at a lot bigger size set up, i dont think 20 F & P set ups is very practical.

2)wind mill blades,
i have noticed that most run 2,3 or 4 blade symetrical set up, engines of all types have had fans used to cool the engines for many years,

the blades used in these set up are asymetrical the reason for this is to stop harmonic's / viabrations through harmonics, eg. go have a look at the tyres on your car you will see the tread is not the same pattern repeted over and over, some 4x4 excempt, due to the noise they make from harmonics if the pattern is the same, some 4x4's tyres scream as they go down the road because of harmoincs with symetrical tread.

airplane propelers do suffer from the same but due to there speed there is many other inherent problems, wing tips reaching super sonic etc. which cause more harmonics so they are dampened to reduce problems and viabration, most propelers on planes are max rpm's are set so super sonic is not quite reached by the prop tips and are most effency is at this speed

3)cogging, hard start
I read how this has been over come by making the F & P have more doozy whatsits ? i know nothing about electronics,
this is only a problem if there is a lack of torque with race cars we do not worrie about hp at all, torque is speed and in racing the diffrence between a car with big torque and one with big hp is phenominel, especialy with a heavy car.
big torque blades on a wind generator should start in lighter winds and with a lot more force

4)generator blades
what would happen if you ran a generator with say 8 or 10 blades with a lot less angle to the wind so it still acted like a 2 or 3 blade for speed would it still run slow enough and produce more start up torque ?

5)generator
can the generator off of a diesel gen set as above be converted to 48v dc so it can be used as a wind gen, the F & P is a ac motor so it mus be able to be done some how ?

6)batterys
I have 2 old electric fork lifs in the back yard of my factory the batterys are fine (gear box's cant be repaired)if these batterys can be used there a lot cheaper than dedicated solar batterys.


My Plan
i have just bought a little 90 acre hobby farm and house,i want to run it completly indipendent from all services, power from wind generators and batterys connecting back to the grid, water from rain water tanks from house/sheds, all waist water going to the gardens/lawns/veggie patch, only toilet water to the septic system.

i am not a greenie BUT i love the idea of sticking it to the government (no tax)and power supplyers rip off artists and green house gas gut'ses

cheers Brett
No Cave Men Allowed

GO really really fast then turn
 
petanque don
Senior Member

Joined: 02/08/2006
Location: Australia
Posts: 212
Posted: 03:33am 08 Nov 2007
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It seems we have different priorities.

My house hold uses more like 20-25 Kw/hr per day for 2 adults and one child.

This includes electric hot water and a spa.

Have you considered the electricity saving possibilities?

If you go down the self sufficient pathway you will need to be frugal with electricity or spend a LOT of money on your system.

If you are concerned about green house gasses the easiest and probably cheapest way to fix this is to purchase green electricity.
 
chaddy

Newbie

Joined: 08/11/2007
Location: Australia
Posts: 3
Posted: 04:00am 08 Nov 2007
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hey petanque don

like i said in my post i dont want to live like a cave man, i love all my new hitech stuff and theres new toys coming out every day

green energy is realy just another way electricity companys can rip off consumers, how many true green energy power plants are there in australia ?
there is a few windmills in sa ran by a electricity company and the same company owns a coal burner ( power plant )so how can you call that green energy one doesnt even come close to off setting the other and they ask a premium price for it (electricity is all fed to the same grid from solar,wind or power stations)

im sorry if this seems a little synical but i have some really bad experiances with electricity companys in the past and they seem to be a rule unto themselfs

cheers Brett


NO Cave Men Allowed :)
No Cave Men Allowed

GO really really fast then turn
 
Gizmo

Admin Group

Joined: 05/06/2004
Location: Australia
Posts: 5116
Posted: 08:51am 08 Nov 2007
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Hi Brett, welcome to the site. Answering some of your questions...

1. The perm mag diesel generators need to be spun fast, much faster than a wind turbine could operate at. They also have to operate within a specific rpm range or they drop their frequency lock, or fly apart! The perm mag types could be modified to run at 200 to 300 rpm, but at a fraction of their rated output.
Yes you would need a lot of F&P's to make that much power.
Having lots of gadgets its fine, but its the power they use when not in use thats the killer. Standby mode, draws a lot more power than most people realise. I have several PC's and a flash entertainment center, I turn my PC and entertainment center off at the wall when I got to bed, and back on when I get home from work. By doing this I would save many kwatts per year, and I dont have to worry about the house burning down while I'm asleep or away.
2. I dont see why asymetrical blades on a windmill couldnt work. Will leave that up to someone else to answer.
3. Yes its a torque issue. Fast blades have little torque at 0 RPM. A bit like a high performance cam in a 4 pot with a single carb trying to tow a trailer.
4. More blades start to interfere with eachother at high speed. Its a windmill rule, less blades = more speed.
5. See 1.
6. Yes forklift batteries are perfect, grab them!

Glenn
Hairy cave man.

The best time to plant a tree was twenty years ago, the second best time is right now.
JAQ
 
Jon Bennett
Newbie

Joined: 01/11/2007
Location: Australia
Posts: 27
Posted: 09:07pm 08 Nov 2007
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One way to cut down on standby power is a Powergenie, they are basicaly a relay unit for 240v power.

Useful for where you have stuff grouped together eg TV, DVD player, set top box etc and people in the house that aren't that into turning things off at the wall.

Set one peice of equipment up as the master eg TV, when it is not "on" it turns the slave side with all the other gear plugged into it off. Doesnt cut out the standby power for the master unit but at least it gets the rest.

regards
jonEdited by Jon Bennett 2007-11-10
 
chaddy

Newbie

Joined: 08/11/2007
Location: Australia
Posts: 3
Posted: 12:30am 09 Nov 2007
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hey gizmo and jon

thanks heaps for the info its great to have some positive ideas and info.
that powergenie what a cool idea that is, needs better marketing cos i can see a huge market for them.
ok my diesel generator idea wont work is there any other way or motor that can work or do i just spend the 15 - 16,000 and buy a 5kw gen set up ?

i have a few 175w solar panels to throw up as well just for good mesure,nothing exceedes like excess

i would much rather have too much than not enough,
The misses is going to go through and work out how many powergenie's we need and stuff at the new place today :)
No Cave Men Allowed

GO really really fast then turn
 
fillm

Guru

Joined: 10/02/2007
Location: Australia
Posts: 730
Posted: 04:31pm 10 Nov 2007
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Hi Chaddy,
If you have just bought a hobby farm and are planning to build or renovate a house I recomend you use as many of the energy effecient appliances / lights / ideas out there that your budget will allow ,it might cost more at the start but its saving you from then as changing later down the track costs a lot more ,as you build high performance cars i'm sure you would know of the parrasites that rob power ,this will make a huge difference to the end cost of your solar/wind suppily, then work out how much power and storage you will require , If you want real power from a wind gen to suppliment solar then look at buying a good proven model eg- westwind have from 3kw to 30 kw ,thats real wind power and there is heaps out there ,but if you want to stuff arround with home made wind mills then make it your hobby and build as you said a lot, my dual on a good day so far has put out .75 kwh so you would need to build 66 and have a good windy day every day , but it gives me enjoyment to muck arround with it , watch the meters go up & down and make improvements , like you I would need 70 to power my house + 30 when the AC is on ,but to change eveything to energy efficient stuff at once to save $1 in elect a day ,its not viable unless our fearless leader comes good with big rebates for doing the atmosphere a favor. But when & if we build again I would do everything possible to be power efficient, untill then ,its pay the bill... Good Luck ... Phill Edited by fillm 2007-11-12
PhillM ...Oz Wind Engineering..Wind Turbine Kits 500W - 5000W ~ F&P Dual Kits ~ GOE222Blades- Voltage Control Parts ------- Tower kits
 
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