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.
|
Forum Index : Windmills : Grand Design Revisited VAWT
Author | Message | ||||
yahoo2 Guru Joined: 05/04/2011 Location: AustraliaPosts: 1166 |
I spotted a repeat of the Grand Design series on the ABC last night, the couple building the house had a geared VAWT on a 40 foot tower as part of the eco house plans. I have finally realised that my life has been completely RUINED by wind turbines. Why? Because I spent the whole episode, looking for trees and obstructions to wind flow, wondering where they would put it, had they done wind speed tests .....mumble,whinge,carp,carry on.. I caught myself grumbling about reliability when the gearbox was mentioned. Complaining that the free standing tower was not suitable for a lenz and would sway under some conditions. Turns out I was right, at the end of the show, the problems they mentioned matched my dour "well all be rooned" Hanrahan style list exactly. I kinda hanker for the old days. I would have seen the turbine and said, " Hey, A wind Turbine....cool!" and then gone back to thinking about girls and beer and stuff. Sigh..... Life was so much simpler. I'm confused, no wait... maybe I'm not... |
||||
Gizmo Admin Group Joined: 05/06/2004 Location: AustraliaPosts: 5078 |
Yeah I caught the end of that show, just enought to see the stationary VAWT, and they talked about the problems they had with the gearbox and wobble. The owner did say later he was a bit naive about a few parts of the home build, and I would say the windmill was a big part of that. Not enough research I would guess. But thats easy to do, I'm in the process of moving in a 2nd hand house to call home, and every other week there is a new problem that I wasn't prepared for, due to my own lack of research. Glenn The best time to plant a tree was twenty years ago, the second best time is right now. JAQ |
||||
Madness Guru Joined: 08/10/2011 Location: AustraliaPosts: 2498 |
Another factor is that it the turbine they installed was the first of it's type to be installed in the field.The company doing it where going to install several more directly after it. Although it was just a single pole it was at least 500 mm in diameter at the base, it should have been quite rigid. While they where in the process of assembling it the woman on the show commented on how she could easily fit inside the pole. There was a big drama because they had planned to put in another type. This had been approved by the local government or who ever. But because they put up a turbine that was not approved (even though it was smaller and not as high) they had to go through a lot of hoops to get approved after there where complaints. The guy said he had a lot of random people pull up at the house and come in and talk about it. Out of these most where in favor of it. Perhaps he might have got better results with the original one they proposed but no details where given about it apart from being bigger and taller. There are only 10 types of people in the world: those who understand binary, and those who don't. |
||||
fillm Guru Joined: 10/02/2007 Location: AustraliaPosts: 730 |
Yea, I saw that episode a while back ..... he was probably given a lovely glossy promotional brocure with lots of bull sh*t figures generated by computer simulation buy a guy who used to sell used cars that told him he would never have to pay for power again.... signed on the bottom line... and now he has a beautiful piece of kenitic art as most VAWTs are. Tie a couple of ropes to it to hang the washing on, would be the best use for it, at least it would be saving the cloths drier cost. PhillM ...Oz Wind Engineering..Wind Turbine Kits 500W - 5000W ~ F&P Dual Kits ~ GOE222Blades- Voltage Control Parts ------- Tower kits |
||||
mac46 Guru Joined: 07/02/2008 Location: United StatesPosts: 412 |
Hey everybody, I did not see the show...what is today? ...international "Bash the VAWT day"??? OK, I'll join in and add my coments, I looked this morning and yep, sure enough, my vawt is still locked down in the storm brackets. I guess the proper thing to do is put a big old 90* gearbox on it and hang the thing sideways...don't know, maybe cut the bugger up for scrap and buy solor pannels. Mac46 I'm just a farmer |
||||
Madness Guru Joined: 08/10/2011 Location: AustraliaPosts: 2498 |
Here it is on youtube Supposed to be a 5KW Skyroota There are only 10 types of people in the world: those who understand binary, and those who don't. |
||||
yahoo2 Guru Joined: 05/04/2011 Location: AustraliaPosts: 1166 |
I remember when I first started repairing turbines, I needed a spot to test them. So I strapped a pole to a tractor fitted the turbine and parked it in the paddock. I live in a very open and windswept location so I thought it would be easy to catch a steady wind. Turns out the small numbers of monster oak trees and sun heating the dark soil cause huge amounts of turbulence below 50 feet. After four days of shifting the tractor I found the perfect spot, a small sandridge on my neighbours farm. I had read ALL of the stuff about selecting a site but nothing prepared me for the reality, if you have a height limit, every location is a compromise. Some of this stuff you just have to learn the hard way. I think he was a little hard on himself, the decision to go with the turbine was made in 2004-05. Solar panels cost a fortune back then, I can understand why they cut them out of the plan. The Suffolk council would have given birth to kittens if he had proposed a 60 foot guyed tower with a HAWT on the top, so this seemed like his only option. Given the same choices 8 years later in 2012 I bet they would cut the turbine, install the panels or go with some greenpower purchase scheme and look very smug. By the way Glenn, I found my old copy of Silicon Chip December 2004 with BUILD YOUR OWN WIND POWERED GENERATOR on the cover, its still a good read, has not dated at all. I'm confused, no wait... maybe I'm not... |
||||
Madness Guru Joined: 08/10/2011 Location: AustraliaPosts: 2498 |
Here is the same turbine from the TV programme, sold on Ebay, say's the company that built it went bust on another forum. Sold on ebay There are only 10 types of people in the world: those who understand binary, and those who don't. |
||||
Gizmo Admin Group Joined: 05/06/2004 Location: AustraliaPosts: 5078 |
hehe. In hindsight, I would have written those articles differently, and used a better design, without the laser cut parts. But at the time, its the best I could come up with. It was only going to be one article, but they wanted more ( must have been a bit quiet on the electronics stories scene ), so I stretched it out as much as I could. I made a little money from it, to put towards the deposit on my first home, so I do have fond memories of my short career as a published author The best time to plant a tree was twenty years ago, the second best time is right now. JAQ |
||||
yahoo2 Guru Joined: 05/04/2011 Location: AustraliaPosts: 1166 |
could be, makes as much sense as some of the other international days! C,mon Mac your going to have to fess up sooner or later. Its not really a a VAWT is it! I watch all the science fiction shows and I know a I'm confused, no wait... maybe I'm not... |
||||
mac46 Guru Joined: 07/02/2008 Location: United StatesPosts: 412 |
Girls, beer,and stuff...still on my mind, I have been said to be "different", but don't think any body has called me an alien...(chuckel chuckel) I believe the "wobble" or out of balance thing is caused by high wing loading at slower speeds...I have solved this somewhat with my vawt by adding a electric starter motor and spining it up to speed with that...Once it gets to spinning pretty good the wings take over and spin it the rest of the way up...and that is with out adding any additional structural supports or frame work to what I already had. Honestly folks, I don't run this thing every day, infact only when I know that I will be around to keep my eye on it, will I start it up. It takes a good wind to make it go...over 10 mph. (This thing scares me). ...I intend to cut the three wings in 1/2 and try running with six wings, only 1/2 as high to see if this will help with the low rpm wobble problem. Its this or make new wings...but not so big and heavy. I'm a long way from getting this thing refined. mac46 I'm just a farmer |
||||
yahoo2 Guru Joined: 05/04/2011 Location: AustraliaPosts: 1166 |
With the turbine on the program the wobble is probably a combination of a wake effect around the pole switching from side to side and the blades losing lift in part of the circle. I bet the pole would sway with no turbine on the top. That is the reason tall chimneys have those spiral deflector. you only have to read some forums that sport a large solar following to see 1001 botched panel installations by supposed professionals, the wind power industry is not on its own here. In the last 6 months I have seen stories in the media saying that the standards of hobbyists far exceed the levels that business can maintain. The apiarist industry in SA is looking for amateur beekepers to help in detecting the spread of pests and disease because they pick them up far sooner. Biodiesel standards testers are admitting that the homebrewers are blitzing the professionals in the quality tests despite using reactors made from scrap. volunteer organisations like the country fire service have an accident rate of almost nill even though they are fighting fires, dealing with chemical spills, storm damage, road accidents, not exactly a desk job. I would say even with your mixed results so far Mac, you would still be in the top 5 percent of turbine builds. I'm confused, no wait... maybe I'm not... |
||||
mac46 Guru Joined: 07/02/2008 Location: United StatesPosts: 412 |
I have noticed on my turbine that what you discribe is very true in effect concerning the wings loading and unloading and it makes a more dramatic effect when the wings are planed out with the circumferance, I still have not decided what angle of attack is best...depends on the wing profile and the wind speed ect. ect. and where the turbine speed levels out once at speed. Things seem to be fairly smooth when it reaches above 45 rpm, even in gusty winds. Currently set at 12* nose in to the center, but not to excited about it. Mac46 I'm just a farmer |
||||
yahoo2 Guru Joined: 05/04/2011 Location: AustraliaPosts: 1166 |
I guess there is quite a bit of flex where your frame has the 90 degree bends. I can only think of a couple of things you could try. Tie a couple of ropes to the top corners of the frame and peg it to the ground like a guy wire to hold some tension on the frame. Make a little roof rack and throw some square 20 litre chemical drums two thirds full of water on top of the turbine to give it some mass and liquid momentum damping. I'm confused, no wait... maybe I'm not... |
||||
Warpspeed Guru Joined: 09/08/2007 Location: AustraliaPosts: 4406 |
O/k I watched the video of the Skyroota spinning it's heart out. Must have been a really decent breeze. But.... Something does not seem quite right...... None of the trees in that video are moving, not the slightest tremor from a single leaf, from what I could see. Maybe it needs 5Kw to drive it ? Cheers, Tony. |
||||
mac46 Guru Joined: 07/02/2008 Location: United StatesPosts: 412 |
Warpspeed, Thats just the Hollywood Effects... I have yet to watch the video...however some,(not all) large vawts have a motor that spins them up to speed-then switches over to a alternator when the wings start flying and speed on up. I am unfamilure with this machine and I'm just ventureing a wild guess here, but you may be correct. Mac46 I'm just a farmer |
||||
Warpspeed Guru Joined: 09/08/2007 Location: AustraliaPosts: 4406 |
I am sure you are right. But it just looks a bit sus. Cheers, Tony. |
||||
Madness Guru Joined: 08/10/2011 Location: AustraliaPosts: 2498 |
It's actually a Skyrota, I was just having some fun with the name. There are only 10 types of people in the world: those who understand binary, and those who don't. |
||||
Warpspeed Guru Joined: 09/08/2007 Location: AustraliaPosts: 4406 |
I know. I like your name better. Cheers, Tony. |
||||
electrondady1 Senior Member Joined: 12/02/2009 Location: CanadaPosts: 208 |
I have finally realised that my life has been completely RUINED by wind turbines. yea, i get that same feeling from time to time as well. when you think about all those hrs. and my electric bill? not a dent. it's too bad that big H rotor didn't put out. |
||||
Print this page |