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.
I stumbled upon this site a few weeks ago and have been thinking about building a wind generator using an F&P since.
I have an on-site sewerage management system which uses an air pump to aerate the grey water to promote bacteria growth. It runs about 8 hours per day and is probably the single biggest consumer of electricity at our place.
I was originally thinking of powering it using solar but the cost of that is still too high. I was quoted about $5,000 for something suitable. I was watching the western rotary vents spinning round one day and it occurred to me that we get a lot of wind here, so maybe wind power would be the way to go - hence I found this site, where I have learnt a lot in 24 hours but nowhere near enough yet (early days).
The main question I have at this stage is whether what I'm proposing is even feasible. The pump I want to power is 110w and it uses about 2kwh per day. It needs to run for a few hours every day, but it doesn't matter if it runs all day one day and not at all the next - so long as it runs on average about 6 to 8 hours per day.
I thought this would be a perfect application for wind or solar because the power doesn't need to be stored. It runs when it runs and when it doesn't, it wont matter.
The question is, will a wind generator provide enough power to run this thing at all, or is it a pipe dream?
Appreciate any input. I'm reading through the other material on the site and trying to work out what components will be required. Very happy to see that there are kits and parts available for a lot of the bits, as I'm not adverse to DIY but time is always my poorest resource.
Thanks!
Downwind Guru Joined: 09/09/2009 Location: AustraliaPosts: 2333
Posted: 01:33am 18 Dec 2009
Copy link to clipboard
Print this post
Welcome aboard,
Why make power in the first place for your application.
Why not have the mill pump air to start with.
What volume of air is needed and at what pressure.
One of the members here just pumps air with his mills anyway i think.
I would think it to be more efficient than making power and converting the power back to air.
The main reason you make power is to be able to store the energy and as you stated you dont need to do this.
I am guessing the volume be to small but you could use something like an old airconditioner compressor from a car and drive it direct with wind.
The load on the mill can be controlled by back pressure.
I have used these as 4wd air compressors and they work well.
The best ones are the early type with 2 big pistons but thr rotary compressors will work to.
Yes I must admit I did start thinking along those lines a couple of days ago. In fact the standard configuration for this system uses a submersible pump that just sucks water off the bottom and fountains it up over the surface where it falls back down, aerating it at the same time. We put the air pump in because they are much cheaper to run.
I guess the only negative I came up with was that if we didn't have any wind for a few days, I'd need a back up, but I could have the air pump connected and just switch it on manually in that case.
So I guess a wind powered water pump or air pump would do it. Starting to sound like I need one of those southern cross windmills, doesn't it?
I'd still like to build one of these F&P jobs though. Maybe it could power the beer fridge :)
Downwind Guru Joined: 09/09/2009 Location: AustraliaPosts: 2333
Posted: 02:05am 18 Dec 2009
Copy link to clipboard
Print this post
I did consider the southern cross style mill to but thought there might be to much sludge for it to be reliable.
Now powering the beer fridge sounds like a worth while project
Would a paddle skimming the surface create enough aeration as have seen simiular in commercial systems.
Perhaps something like an old radiator fan from a car paddleing around just below surface.
If so a vawt might do the job.
Just had a conference with the man who maintains the SupaTreat system (my old man). Apparently I've been labouring under a couple of misconceptions: too much air can also be a bad thing, and it pretty much needs to aerate every day. They have them set to come on at different times of the day, with scheduled breaks that give the little microbes time to feed and grow. They also aerate for 16 hours, not 8.
I think that puts me back to using electricity and I'll have to store it. But I haven't given up on the direct method yet. I'll run the paddle idea past him. Trouble is the tank is so full of plumbing there's not a lot of room for anything of any size.
Back to the original question though, is it feasible to get 2kwh out of a wind generator over the course of a day (given available wind of course)?
MacGyver Guru Joined: 12/05/2009 Location: United StatesPosts: 1329
Posted: 03:00am 18 Dec 2009
Copy link to clipboard
Print this post
[Quote=Downwind]
One of the members here just pumps air with his mills anyway i think.
That'd be me, most likely. All my windmills pump air. I store it at around 40 psig and use it to run little engines I make (hobby).
If you've ever owned a fish tank, you surely know that you can train a stream of air bubbles up a tube and their rise against gravity will drag an equal volume of water along with it. Using a screen on the inlet, may allow you to use this method to "pump" water while aerating it at the same time -- all in one fell swoop!
I usually use HAWT (horizontal-axis wind turbine) designs, but because of "neighbor problems" I'm in the process of switching over to VAWT (vertical).
My neighbors are constantly complaining that birds occasionally get "vaporized" in the blades and they're also afraid of what might happen if the thing comes apart in high wind. Hey, that's a no-brainer: they'll all DIE. Duh!
So, I'm switching to VAWT mills.
The down side to VAWT is power -- they're slow and not very powerful unless you build them large. I'm working up a blade array that will be manufactured out of foam and be literally two HUGE scoops (like those corn chips designed to gather dip) sticking out into the wind flow.
The up side of VAWT is there's only one moving part. My new design is (a remake of an old one) going to feature a "swash plate" mounted on the main (vertical) shaft just under the blades and atop the tower. Mounted to the tower adjacent to the swash plate is the energy-transfer mechanism and the pump.
As the thing spins, the plate 'wobbles' up and down when viewed from a stationary position to the side. This plate is tracked by two little wheels attached to a "cross-head" (steam-engine talk) that translates the 'wobble' into back-and-forth strokes.
To this is attached a plastic bicycle pump ($10!) that pumps a gulp of air in each direction. The pump and follower are permanently mounted to the tower and do not move. For this reason, there needs to be NO transfer mechanism. The compressed air flows down the tower through a copper tube to a ball valve at the base and then off to a receiver (or your cesspool). If the wind gets out of control, merely shut off the valve and the pump will stop after it builds a dead-head of pressure; in turn halting the blades from spinning.
If you live way out in the country (like I don't), you could merely up-size the blades and mount several pumps on the tower, each one running off the single swash plate!
Depending on how much "yard" you have, you could mount several of these rascals and feed them all into one containment vessel, then bleed off the amount of air you need for your cesspool aeration project and save the rest for a less-windy day.
The design (size mainly) of the blades depends on your average wind speed. Direction doesn't matter, since the VAWT responds to wind from any and all directions without any yaw gear (tail).
I've done this before, so as soon as I can cannibalize a few of the parts from previous mills, I'll post some pictures and you can just copy my work if you want.
Another "up" factor to the VAWT is you don't really need a lathe to make the thing work. Using a lathe would be way better, but it's more a luxury in this case than a necessity. HAWT mills, on the other hand, really need the balance a lathe provides when manufacturing all the little pieces and so on.
Good, eh? (say it fast and it'll sound like you're Australian!) :O)
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
Well, I never thought of storing the air, but that makes as much sense as storing power if air is what you want. I suppose you could rig up an electronically controlled valve to switch it off and on.
So are we talking air at the PSI that you might get from a compressor? I mean, could you run air-powered tools from it?
Haven't read too much about VAWT yet, only just become dimly aware of it and have 'stumbled' on a couple of VAWT-related sites recently (since I updated my Stumble Upon settings to include alternate power).
I'm on 2 1/2 acres on the edge of town. Neighbours aren't much of an issue, haven't got any at present.
I was just looking at the rotary vents spinning again and wondering if I could attach a small generator to them somehow and charge a battery to run our 12v downlights... Edited by silentC 2009-12-19
Downwind Guru Joined: 09/09/2009 Location: AustraliaPosts: 2333
Posted: 03:22am 18 Dec 2009
Copy link to clipboard
Print this post
MacGyver
Have you considered the car aircon compressor as the rotary ones are simiular to your swash plate design.
They are chaep at the wrecker as most times never reused once removed.
You would be the first person i know of that has recorded a bird kill with a wind generator.
You must have some dumb birds over there.(blonde Ha??)
Pete.Sometimes it just works
MacGyver Guru Joined: 12/05/2009 Location: United StatesPosts: 1329
Posted: 04:04am 18 Dec 2009
Copy link to clipboard
Print this post
As for the car air compressor, if it's the one I'm thinking about, it requires lubrication. I like simple stuff. My air compressor is single-cylinder, double-acting and costs $10 at Target, so I'm sticking with it for the time being.
Also, a note on "rotary" compressors. These are usually "sliding-vane" compressors, which require both lubrication as well as HIGH speed. The windmills I make offer neither, so I use the little bicycle pump and it works like a charm.
As for the birds, I think it has to do with the size of my HAWTs. They're only 36 inches in diameter and when they're running flat out, the blades don't show much against the sky.
The guy next door has umpteen million bird feeders in his back yard and I think when the birds get bored eating, they hop over to my side of the fence to get some thrills trying to fly through the windmill! It's eaten several. I've never actually seen it happen, but I've heard the "thung" sound a time or two and found feathers all over the ground.
I'm sure he'll have something negative to say about the VAWT too, but I really don't care much at this point. His weeping willow tree root grew through the side of my in-ground swimming pool and ruined it, so he really doesn't have much room to gripe about my silly windmills and dead birds, if you ask me.
On the subject of "dumb" birds, I've noticed that when they feed on the little red pyricantha berries, they also fly into walls and try to fly through glass windows. It must make them drunk (or blond!).
You haven't lived until you've stood at the kitchen window washing a glass only to look up and see a bird making a bee-line for you, then "Whump!" -- it flies into the window and sputters around on the ground for a minute or so before heading back to the little red berries for a second go at it!.
[Quote]Well, I never thought of storing the air
Actually, storing wind power as compressed air is a really great method. I store it in old water heaters (I'm a plumber) and put a safety valve on the system at 40 psig so I don't build a bomb (my neighbor would really have a cow if he knew!). With compressed air stored away, I can run it through any of my little air engines I make (steam conversions) and couple that to a generator if I want to manufacture electricity. This way, all the fancy stuff is down on the ground and the only thing flying around atop the tower is the air pump.
To do this on a scale large enough to run a house, I'm in the process of building a 6-cylinder, oscillating air engine. Each cylinder and piston are actually square in shape (makes it build-able without a lathe for those who don't have that luxury) and the hope is it will run out at about 7 h.p.
Seven horsepower is enough to run a 5KVA generator and there you have it. So far, I'm building a single-cylinder one to get the bugs out before tackling the 6-place gadget. When (if!) I finish them, I'll post pictures for show & tell.
Edited by MacGyver 2009-12-19Nothing difficult is ever easy!
Perhaps better stated in the words of Morgan Freeman,
"Where there is no struggle, there is no progress!"
Copeville, Texas
Downwind Guru Joined: 09/09/2009 Location: AustraliaPosts: 2333
Posted: 07:03am 18 Dec 2009
Copy link to clipboard
Print this post
You made me laugh with the Wthump of bird into window as have seen it many times too, not sure if they have been into the red berries over here as well.
I also think bird feeders do as much damage to things as they do good. Its not natural.
For those who complain about windmills killing birds need to get a life and wake up some, as the stray cats from discarded / neglected pets do far more damage on a wider scale than the odd mill ruffling a few feathers.
A study done on a commercial wind farm here for 2 months did not record even 1 close call of a bird being struck by a turbine blade the only contact the mills had with birds was when the birds came to rest on the mills for a spell.
You might want to try putting up some of those hawk kites that blow around in the wind and help keep the birds away, they use them here in the vineyards as a deterant, might save the neighbour a bit on bird seed.
Pitty about your pool, It sounds a bit rooted!!
As for the compressors yes they do require lube and i have run some dry for a good while with the odd squirt of oil in the inlet from time to time when i have remembered. ( not to often )
They seem to handle it ok and if they do crap out they are cheap and easy to replace.
It was just a thought and if you are happy with what you have then why change.
Pete.
Sometimes it just works
VK4AYQ Guru Joined: 02/12/2009 Location: AustraliaPosts: 2539
Posted: 06:32pm 19 Dec 2009
Copy link to clipboard
Print this post
Hi all
I will put in my 2 bob's worth here, many years ago I used to make VS mills for various things une simular to yours was agitating of sewerage in treatment. driving a 6 ft dia propeller 6" under the surface that agitated and to some extent airated the pond, Another one was used in a methane gererator plant as a agitator some where used for waterpumping stock wated on farms. One small one I used to supply compressed air to my workshop using a car diff as a right angle drive step up, it drives a 5cfm comperessor in a slight breeze all of them worked in a breeze that you could feel on your face 4/5 mph bottom of rotor 12 ft above ground to get above boundry layer so no need for a big tall expensive tower. A good source of air storage tanks is out of time car gas tanks put some linseed oil in and roll around to coat the inside, leave in the sun for a couple of weeks to set the oil then fill up full with water and do a pressuire test to 150 psi, do not use air, if it lets go you have bomb on your hands. Bigger unit bigger compressor bigger storage with timed release through a low pressure regulator.
All the best
BobFoolin Around
VK4AYQ Guru Joined: 02/12/2009 Location: AustraliaPosts: 2539
Posted: 06:36pm 19 Dec 2009
Copy link to clipboard
Print this post
I was watching the western rotary vents spinning round one day and it occurred to me that we get a lot of wind here, so maybe wind power would be the way to go - hence I found this site, where I have learnt a lot in 24 hours but nowhere near enough yet (early days).
There is a guy selling these on ebay for around $900 with 300 wats out enough to run your lights and maybee a beer fridge too
BobFoolin Around
Perry Senior Member Joined: 19/11/2009 Location: Posts: 190
Posted: 11:34am 20 Dec 2009
Copy link to clipboard
Print this post
Those spinning vents on ebay are a complete scam. Do not let your expectations be misled.
Perry
VK4AYQ Guru Joined: 02/12/2009 Location: AustraliaPosts: 2539
Posted: 12:44am 21 Dec 2009
Copy link to clipboard
Print this post
Hi Perry
Thanks for that, I havnt tried them myself I just made the comment that they where there {Caviet Emptor}
I made a small one years ago 6 vane 3ft high 2 ft in diameter and was able to get 500watts out of it in a stiff breeze so I thought 300 was doable in the right conditions.
I noticed that he is using the 500 watt chinese VS alternater from memory it is 500 watts at 300+ RPM but would be difficult to achieve that with a spinner style turbine in less than a strong wind.
All the best
BobFoolin Around
Perry Senior Member Joined: 19/11/2009 Location: Posts: 190
Posted: 01:19am 21 Dec 2009
Copy link to clipboard
Print this post
You made 500 watts from a 3ftx2ft VAWT? Must have been quite a bit more than a stiff breeze!
Perry
VK4AYQ Guru Joined: 02/12/2009 Location: AustraliaPosts: 2539
Posted: 01:54am 21 Dec 2009
Copy link to clipboard
Print this post
Hi Perry
It did work but was to expensive to make as it used 6 special aerofoil blades designed by a friend who was an aeronautical engineer, not my pressed tin ones that only did 200 watts on the same rotor.
He used a special aerofoil section with vortex generators, wish I still had the plans as could probably get them moulded out of foam these days much cheaper than fabricating them. The vortex gererators made the big difference from memory about 30% more torque.
It spun faster than the wind speed like a wind turbine speed is greater than the wind speed, my paddle blades went slightly less than wind speed.
All the best
BobFoolin Around
VK4AYQ Guru Joined: 02/12/2009 Location: AustraliaPosts: 2539
Posted: 01:59am 21 Dec 2009
Copy link to clipboard
Print this post
Me again
I didnt have a airspeed indicator at the time but would say about 6 to 10 Kts by observing the tree tops As per my old Aero training manual.
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.
Print this post
