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shawn

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Joined: 30/03/2010
Location: New Zealand
Posts: 210

Posted: 12:05am 30 Mar 2010

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New member needing some help destroyd first windmill in high winds so must improve next but first some info so you can help have buit dual 1/80 in star and 1/100 in delta will use gordens cap mods but will use someone to help with this.am going 24 volts.my question is blade size am going with wood and have made hub for this am thinking 3 meter with tsr of 6 have used hughpigots info to build last mill

niall1

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Joined: 20/11/2008
Location: Ireland
Posts: 331

Posted: 01:14am 30 Mar 2010

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hi Shawn

first off well done on trying out your own ideas .....destroying stuff can be part of the course...

a bit more information is needed shawn...do you want to go with a Piggott design mill or an f&P ...if its Hughs you need to stick rigidly to the design ...if f&P then others on the site have the know how ...

what was the first...last mill ? Edited by niall1 2010-03-31

niall

shawn

Senior Member

Joined: 30/03/2010
Location: New Zealand
Posts: 210

Posted: 07:34am 30 Mar 2010

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After reading more at this great site I do have axflux envy but this mill will have f&P stators I have a thing for wooden taperd/twisterd blades most blades on f&p mills on this site seem two be plastic or alloy am not wanting to set any records just improve on last mill .

As for my first mill I had wooden blades Hughs specs 4 meter diameter with tip speed ratio of 8 on a horse float hub with pushbike gears/chain running 2 f&p stators = poor startup and when real wind blows is overpowerd buy blades not a good mill but I did not know about this site then.

KarlJ

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Joined: 19/05/2008
Location: Australia
Posts: 1178

Posted: 11:29am 30 Mar 2010

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Check out my farm mill look up the post.
100Sdelta is good for 600-800W at 55V bat at 24V i'd be splitting in half ie 2X7C for the
80S I'd be going for the traditional 7x2C rewire in star but Phill has just built one just like yours so wait for him to chime in.

Direct drive and MAX 3.0M is the go, slightly less say 2.8m you'll mill a little down the bottom but will rev up harder than a 3m mill and thus funnily enough you'll get more power.

Mine is 3.0M into 48V battery then Grid

after 60 days up and running i'm averaging 1.3KW /day
and the wind has and is at this time of the year poor at my site, cant wait for the windy season, should make 5/day.

hoping for 2000KW/hr/annum to get my 4 year ROI.

good luck with the blades, aim for 100mm offset to start, then dial it back to make it run harder until the quest for power decreases due to fear!

theoretical max for a sweet dual stator is 1200W that gives good all round performance, 1200W you'll see very rarely though and it will be a howling gale!

Karl

Luck favours the well prepared

shawn

Senior Member

Joined: 30/03/2010
Location: New Zealand
Posts: 210

Posted: 07:03pm 30 Mar 2010

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Thanks guys yes 80s I rewired 7x2c star and 100s 2x7c delta. will take your advice on blade max of 2.8m now shaping them mabee 14 deg at base 5 deg at tip????

Know what fear means have had chain come off mill in gale free weeling 4.0m blades nearly filled my pants!!

oztules

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Joined: 26/07/2007
Location: Australia
Posts: 1686

Posted: 09:50pm 30 Mar 2010

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[quote]Know what fear means have had chain come off mill in gale free weeling 4.0m blades nearly filled my pants!![/quote]

I have 4m blades, and the thought of them running free in a good wind scares me into next week

......oztules

Village idiot...or... just another hack out of his depth

shawn

Senior Member

Joined: 30/03/2010
Location: New Zealand
Posts: 210

Posted: 06:40am 31 Mar 2010

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Cool sounds like the basics are sorted ??? not sure myself. I was confident until looking through this site then realised how much a total beginer I am the internet made it all look so easy but this is definitly not the case.
As mentiond above caps I only almost understand the same could be said with all electrionics including computers.
will try to put photos for all to see don't be to mean I have an old welder A anvil big hammer 9 inch grinder/cutoffweel small drill and A pear tree for shelter and yes oztules a chainsaw.
Only have diesal gen for power grid to far away to think about connecting.

Downwind

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Joined: 09/09/2009
Location: Australia
Posts: 2333

Posted: 01:17pm 31 Mar 2010

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Your list of tools might be limited but you have the most important thing ....desire.

I work from not much more than you have and get a reasonable result.
It is a bit harder than with a lathe and a shop full of equipment but where there is a will you will find a way.
Or should that be where there is wind you will find a way.

Pete.

Sometimes it just works

KarlJ

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Joined: 19/05/2008
Location: Australia
Posts: 1178

Posted: 03:46pm 31 Mar 2010

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whats the system voltage?
I'm going to assume 24V
if not below does not apply

That combo should work well the 100S good for a 400rpm cutin but twice the current than at 48V
going to need to watch the cable size carefully.
800W++ @24V =33A -even with 2 15A extension leads running down the mast its getting into decent losses.
Keep everything short and neat.

Luck favours the well prepared

shawn

Senior Member

Joined: 30/03/2010
Location: New Zealand
Posts: 210

Posted: 07:45pm 31 Mar 2010

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Thankyou Karl I have not bought invertor yet so at this stage could change voltage to 48 have plenty of stators.
the only reason started with 24 is the lights in house are 24volt leds I strung together.
yes have two extension cords running down the tower which does not hinge yet so I have crows nest!
Im sure there will be pros and cons with the different voltages which you guys would be better with than I.
tower is 33 meters downwind from house thought I would build small shed next to house for batteres and invertor
will want at latter stage to add pv into system but have no funds for this yet good wind site
trees only grow branches on one side of them.
also plenty of room for more windmills.

GWatPE

Senior Member

Joined: 01/09/2006
Location: Australia
Posts: 2127

Posted: 10:22pm 31 Mar 2010

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Hi Shawn,

Tree flagging is a sign of a good wind site. Sounds promising, for when you get funds to go.

Gordon.

become more energy aware

shawn

Senior Member

Joined: 30/03/2010
Location: New Zealand
Posts: 210

Posted: 12:38am 01 Apr 2010

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Pleased two have all the big guns watching me!

power storage invertors charge control and lots more I am sure I will have to take the gorse out of the pocket somtime
But what DIY er ever waited for funds!

KarlJ

Guru

Joined: 19/05/2008
Location: Australia
Posts: 1178

Posted: 01:27pm 01 Apr 2010

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My tip for the inverter, technically here in Aus if you bury cable it needs to be 600mm deep regardless of low or high voltage, thus if you intend building something to house batteries / inverters better it be out at the mill site as line losses are much less at 240V than they are at 24 or 48V.

again I found this out the hard way.

I would assume that the PVE1200 is OK for use in NZ, just drop them a line at www.latronics.com.au and they can advise.

if so they can be had for under $1800 AUD and best yet you can run a hybrid system with a few hundred watts of solar to go with them, thus making the proposition more viable.

EG inverter rated at>1200 W and mill god for 5-600W in normal winds could easily run 800W of panels and when the sun is shing and the wind blowing your charge controller either disconnect the solar or run your dump load.

Luck favours the well prepared

shawn

Senior Member

Joined: 30/03/2010
Location: New Zealand
Posts: 210

Posted: 07:50pm 01 Apr 2010

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Karl thankyou for your help this is were I get stuck.
with batteries at mill will I have to run another cable from house roof solar out to mill? and under boring winds eg mill not furling its the power pushing into batteries that keeps the mill at bay therfore if mill Along way away will it not just spin up abit faster untill volts high enough for it to be under load ?

Downwind

Guru

Joined: 09/09/2009
Location: Australia
Posts: 2333

Posted: 02:46am 02 Apr 2010

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I would keep the batteries closer to the solar as this is the more reliable energy source throughout the year.

Then the losses from the mill is just something you will have to live with.

As i understand it there is no restrictions on depth for a low voltage DC cable, so it will also be cheaper than a 600mm deep trench to run the mains cable to the house.

The whole thing is you are going to have losses and its just a matter of which way around you put them...Solar...or....Wind, if it were me i would put them in the wind side.

Is there any reason the solar cant be moved closer to the mill?

Pete.

Sometimes it just works

shawn

Senior Member

Joined: 30/03/2010
Location: New Zealand
Posts: 210

Posted: 08:48am 02 Apr 2010

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Hmmm much to think about have to agree with pete on this karl will keep batteries in small shed saves on permits mabee not enough roof space for solar on it also so house better bet and close to house could use dump load power for hot water etc... without running another long cable.

Downwind

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Joined: 09/09/2009
Location: Australia
Posts: 2333

Posted: 11:54am 02 Apr 2010

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Hi Shawn

The best solution is as Karl surgested the most practical solution for your setup is what i thought above.

The reason i asked about moving the solar panels closer to the mill was to consider putting them on a tracking system which will give you around 25% more power out over the day.

There is this funny stigma that the panels on the roof is the best place for them........What is 15 foot going to change in output?

If you have the space and ability to build a tracker than i would go this way.

I built one for a friend who lives off grid, it might not be the best design but it works well and gives 25+% return.

My thoughts were strong and robust on a very cheap budget. It needed to with stand a high wind area.

I used a car diff and a gearbox that was lurking under the bench with a 400:1 ratio.

We had intended to have tricky electronics tracking the sun and wind, but with tests done, we settled for a manual adjust tilt (once a year) and a basic system that moved in +/-15 minute intervals a set distance throught the day, then returns to a given point at sun up.
There is 2 travel times used ..summer and winter.

There is many trackers others have built on the forum.
Some have many more features, and all work to a positive result and is a credit to the people who constructed them.

Mine was agricultural, strong and cheap that gave a 25% more output return.

Some more food for thought while you weigh the options up.

Maybe it is worth running a 240v ac cable 600mm deep, if a tracker suits location.

Pete.

Sometimes it just works

KarlJ

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Joined: 19/05/2008
Location: Australia
Posts: 1178

Posted: 05:24am 03 Apr 2010

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OK
i didnt bury my cables 600mm deep but the rules for LV and HV are the same ANY buried cable is technically supposed to be 600mm deep.

PVcool do some great trackers for $1000 AUD (that will hold about 1.5KW (12m2) of panels plus pole and a few hundred bucks in concrete.

Kinda convenient if you havent already dug the hole for your wind turbine, could do both at the same time.

This will give your solar 30% boost and keep all the equipment in one spot albeit a walk from the house

Luck favours the well prepared

Downwind

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Joined: 09/09/2009
Location: Australia
Posts: 2333

Posted: 06:49am 03 Apr 2010

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I dont agree with the law as 600mm deep for lv cables as i installed garden lighting for many years and this did not require 600mm depth.

The amount of telstra cables i have dug up just under the surface also proves this.

To be safe it is good to go the 600mm depth but not needed if it poses a problem or a high exspence.

Pete.

Sometimes it just works

AllanS
Regular Member

Joined: 05/06/2006
Location:
Posts: 67

Posted: 06:59am 03 Apr 2010

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Hi Downwind,

I like that tracker.

What if you put some white colorbond round the perimeter at 45 degrees, so the PV panels become the base of a bowl. I wonder how much the glare would increase output. Another 20% would be worth the effort, assuming the thing didn't overheat in summer... (Since you're not using mirrors, it might not void the warranty.)

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