Low wind power - Best practices

[zowwie438]

Howdy all,

First... I would like to thank Mr. Piggott for giving me the bug of wind.   Him and the local gas company that is.

OK... Here is the deal.

1. Last years gas heat bills totalled $680.00 per month!
   
2. We have a monster house that sits at base of hill that is bombarded by valley/mountain winds.
   
3. I am great with electronics... But woodworking is not my area (blades).
   
   

I have read a great deal, but I have some questions that I would like to post to obtain some feedback on my thinking.

Blades:

Larger blades operate better in low wind, but greater force is placed against mounting assembly when winds get high.   With 10' span, wind force can be as great as 1,000+ pounds at 50MPH.

Please provide tips on pre-made blade assemblies and best material... Wood, fiber, pvc, etc.

Stator:

Because I was originally raised in Kentucky... I am bound by genenic coding to build the Volvo rotor design, but I may substitute ford or chev parts to maintain my integrity.

I have concerns about burning up coils... But I wish to build a 24V system.   Any recommendations on rotor types?   Wire size?   Best vendor for enamle coated wire?

Roof Mounting:

Although most people frown against roof mounting... This is where I would like to mount the unit.    It will be sitting on top of a 1908 structure with 14" thick brick walls.    The roof is wood, but large lag bolts can be placed to help secure load.

Any recommendations on tri-pod configs?   Steel cross members VS guyw wires?

Magnets:

OUCH... This was supposed to be a cheap project.   I see these things are very expensive, but I don't wish to go through the expense of setting this thing up and take shortcuts on the mags.

Other than ordering them online... Does anyone know of any items out there in the retail world that contain the high energy NEO mags?

Wedge, square, round, etc.   I have read that wedge is best for the Piggott design, but I can't find the things online.    Any input?

Insurance:

I hate insurance companies... But does anyone know if US home owners insurance companies require extra riders for windmills that are 10 foot in diam or less?

Starter Kits:

What is the best recommended starter kit for someone just starting to build their own rotor, stator, and mill?

Box fan setup?

Heating Elements:

I was hoping to output ALL available power from the mill directly into heating elements for our two 55 gal hot water heaters.   Some juice may be used to operate a low amperage circulating pump for the water heaters.

This hot water heat will eventually be routed across a hydrofoil coil for our furnace to generate heat for the house during the winter.

As a backup... Electric will power the water heaters, OR we can fire up the gas for the furnace via a relay control if the temp on the water heaters is too low.

Does anyone have any input here?   Would it be best to drive a heating element directly into a 55 gal holder?   OR  heat 5 gal at a time and when it reaches temp, then transfer that hot water to holding tank.

I have heard that it's much easier to heat smaller amounts of water than a large tank.

The other option would be to heat the 5 gal... But make it antifreeze or some other liquid that can heat rapidly and then use a heat exhanger to transfer that heat to the main holding tank.

Does anyone have any experience on what liquid would be best for retaining and heating the fastest without causing a fire hazard?

Winter Time & Wind:

Because the magnets must be as close as possible to the stator... Has anyone experienced freezing issues?

Best Stator Design... AKA most bang for the buck?

As I am sure... Everyone here has their own preference but bottom line we are all trying to get as much mojo from the wind as possible.

What stator design is best?   Stacked, not stacked... Dual magnets, etc?

Remember that this is a LOW wind setup.

OK... I think thats enough questions for my first post. :-)

Keep up the good work guys and gals!   I will be sure to post a series of photos during my project so others can reap the rewards of my failures. LOL

--Zowwie

[John II]

Hi Zowwie:

Wow what a heating bill !

I don't have a lot of input and hopefully others will have. But I do have a few thoughts : )

(my 2 cents worth of thoughts anyhow )

I don't care how sturdy your house is, I think you'll be really sorry mounting even the best balanced wind unit on your house ! A house almost acts like the sounding board of a music instrument such as a guitar ! At the best, chances are you won't get a moments worth of sleep. And at the worst, it could damage your house.

I would highly suggest that if you want to take advantage of the air pressure increase of the wind flowing over your house, that you place a tower in the right location from your house to do the same job.

Another thought is, if you are just interested in heating water only, Is to wind your stator for 120 volt output. Your wiring loss will be small, you can use standard wiring and water heating elements which occasionally burn out will be low cost to purchase and easy to replace.

My 3rd thought, is unless you have consistent gale force winds, a 10 foot diameter blade will not make that big of impact on your heating bill. But of course, any help on that bill will likely be greatly appreciated ; )

" Larger blades operate better in low wind, but greater force is placed against mounting assembly when winds get high. With 10' span, wind force can be as great as 1,000+ pounds at 50MPH. "

(4th ) While this is true, this is why wind generator manufactures make their units start turning out of the wind at around 30 mph or so. Otherwise you will need a much larger generator to take advantage of all that 50 mph wind power. Then with this huge generator on your wind machine, if you are not careful, it will be hard to get turning in extremely light winds and preform poorly in low winds.

John II

[iFred]

Hi Zowwie

I have a suggestion to make only because you have so many questions that I think most of us are overwhelmed and also because most of these questions have already been answered in this chat board already.

Please take some time and do a "search" located in the "menu" located in the left top of this chat board. Also take some time and read what others are doing before you start a project of this scale, not to limit your potential but to start smaller and work your way up gradually till you understand the technology sufficiently. All of this can be overwhelming I know which is why I am suggesting this. There is another reason too, if you where to start small and work your way up and set goals then I can assure you that you will save your self grief and expense later. Some of these projects are costly, they must be thought thru and worked out gradually or else your funds will deplete quickly.

Continue with your research, read and continue to learn of better ways to do things and I am sure you will do fine. Ask a single good qustion from time to time, your responses will increase and your knowledge will too. I wish you the best of luck!

Fred.

[finnsawyer]

You seem to be telling a contradictory story.  A house bombarded by low? winter winds.  Anyway here's my idea.  You can save a lot of money by using automotive type alternators.  Unfortunately these require 800 to 1000 rpm to produce usable power.  You would need a transmission.  Design a blade system with a larger than normal hub (say 20 to 33 percent of the radius).  Use a pneumatic tire to take the power off of the inside of the hub at its maximum radius.  This should allow a speed up of a factor of three in the alternator.  The energy hitting the hub is not lost (at least according to theory), but shows up at the periphery of the hub as a speed up of the air stream.  Consequently a lower pitch angle at the hub would be needed.  The air pressure in the tire automatically tensions the transmission.  Also shorter blades and less carving are needed due to the large hub.

[Ungrounded Lightning Rod]

Design a blade system with a larger than normal hub (say 20 to 33 percent of the radius).  Use a pneumatic tire to take the power off of the inside of the hub at its maximum radius.

I'd just mount a BIG V-belt pulley (like one off a clothes dryer) on the back of the blades.  You can get 'em (with narrow spokes) at your hardware store, (along with v-belts of various sizes).  Being mostly open it won't resist the wind very much.

Then just use a v-belt to the alternator's existing pulley.

Be sure to retension it after it's spun for a hour or so.  Then you'll be set for several years before you have to replace the v-belt.

V-belts are reasonably efficient.  (They're handling a couple horsepower, at about 745 watts each.  If they lost a lot of it as heat they'd self-destruct very quickly.)  You'll probably lose a lot more to your alternator's field excitation than you do to the v-belt.

[Nando]

Zowwie:

First: You stop dreaming

Second: Measure the available wind

Third : Do not mount the mill to the house structure.

Fourth: Once you have the available wind and power then you decided if it is worthy to have PMA VERSUS and Induction Generator -- quite cheaper and can be compensated by increasing the mill diameter.

Fifth: Check your pockets to see if you have enough money for this DREAM !!.

Sixth : Get books and learn about wind, Wind mills, & alternative energy costs versus what you ae now paying and in the future.

Then start asking and asking and asking and when you can not ask anymore start asking again.

Regards

Nando

[Ungrounded Lightning Rod]

Although most people frown against roof mounting... This is where I would like to mount the unit.    It will be sitting on top of a 1908 structure with 14" thick brick walls.

NEVER mount anything that creates vibration on ANY building with a brick wall.  (Especially an old one.)  They'll stand for centuries, but will crumble when you start shaking them.  The vibrations break up the mortar, and you're left with a pile of bricks that is being shaken apart.

Do a search on "brick earthquake vibration" for horror stories.

I hate insurance companies... But does anyone know if US home owners insurance companies require extra riders for windmills that are 10 foot in diam or less?

You'll hate them even more when they cancel your insurance for mounting a windmill on a masonry house - or refuse to pay off after it shakes something apart.

[zowwie438]

All,

Thank you for the feedback.

A couple notes for those who posted...

1)

I ordered Mr. Piggott's literature.   That's a start.

2)

Built my first small mill over the weekend using spare parts from old drywall plastic buckets for speed testing.   Connected to electronic reed switch and linux machine to calculate RPM's and log date/times.

PS:  Plastic paint buckets or old drywall buckets are very easy to make into a Savonius rotor.

3)

I liked the one idea of creating a 120V stator... But I can't recall seeing any plans for this.   I have seen 12, 48, etc.   But not 120.   Any links?

4)

About the reading of posts, groups... I have done TONS of reading the past week or so, just not this entire group.   It would be much easier to read through this group if they used some other web based software like PHPBB (free).   I will try to read through more as time goes.

5)

Costs... Yes.   It does appear that this project will take a great deal of cost.  Escpecially regarding lumber and magnets.

6)

Brick structures... Yeah.   Common sense would say not to mount anything onto a house that shakes, but then again we have two train tracks 1 1/2 blocks away both east and west and our house is constantly shaking when the big ones go by.

I figured if it has lasted 100 years with trains (even the old steamers)... What is a 10 foot mill going to do?

However... You guys and gals have been down this road, so I will take the advise of others and start searching for a tower with the proper ratings.

Summary:

Thanks to all.   Best wishes on you adventures and thank you for taking the time to contribute to the group.

[commanda]

My 2 cents worth.

If all you want to do is heat water for Central Heating, Go Solar. Solar collectors are easy to build & low maintenance. Wooden box, glass top, corrugated iron sheet painted black, some copper tube, and a small pump to circulate the water if you can't make it thermosiphon.

Amanda Commanda