Anemometer Tower

[luv2weld]

I've been following this thread from the beginning. The thing that bothered me the most was the guy spacing on the ground.
The "footprint". All of the commercially available towers and kits specify a minimum of 50% of tower height out from the base of the tower.
Some go so far as to recommend 100% of tower height. Using this info, your anchors should be 80 to 160 feet from the base of the tower.
I know you are going to have minimum lateral loading. But the one thing you have not planned for is the "once in a 150 year" wind gust.
With the anchors too close to the base, you have nothing to keep that thing in the air. It would literally be a "push-over".

OK, the upside is you have venison for dinner.
The downside is you have to start all over again. And hopefully no thing or no one was in the way when it came down.

Please remember the area around a tower is called"the Kill Zone" for a good reason.

Also, please don't think we are all stuffy muckity mucks. I hate cigars!

Not trying to say "If you don't do it my way, you're wrong!" Just trying to say I have put a few towers in the air. It can get scary real quick.
Even when you have tried to follow all recommended procedures. I've also had a tower fall when a guy wire failed. Not a pretty picture.
And the feeling in the pit of your stomach is something you will not forget and never want to experience again!

I can't say why the others are responding the way they are. I can say my person thinking is----
"It is always easier (and cheaper) to over-build it the first time, than to have to pick up the pieces and start over".


Ralph

[Jerryflyguy21]

Thanks Ralph,  I have pushed my guy spacing out from the original concept. I did some more study of other towers 'out there' and found similar data as you'd stated in having them spaced at 1/2 the height of the tower.  I will do some more numbers w/ the new tubing size and a 50m/s wind rating which would be fairly close to the loading seen when lifting w/ a gin pole. I will rate it for a 2G load while using the gin pole [sudden stop or something] and a FOS of 3 on the vertical loads on the tower [at a minimum].  I am not one of those people who disregards safety as a rule. I'm an ATPL rated pilot so.. safety is a familiar thing , I didn't get to flying twin turboprops by being unsafe. I do intend to base my level of safety in numbers vs just guessing. This is a two year [maybe three year tops] install so it has a finite expected life.

I have found [I think] a cheaper supply of guy wire cabling, such that up sizing to 3/16" cable would be a non-issue, rather than going with pre-made assemblies I can do the 'build your own' by just purchasing the parts and assembling them as I need them. Also, the idea of a 160ft tower is pretty much off the table, I think if I had a 100 or 120ft [tops] tower i should be able to get the data range i need and any extrapolation up to the 50m level would be accurate enough to confidently stand behind.

Thanks for the great input!

JFG

[birdhouse]

JFG- i've got a PDF from an out of business turbine company for 106' and their 127' towers.  its 38 pages of really good info, they do a tight guy radius and insane amounts of concrete to accomplish this, but they were engineered, and i'm sure you could extrapolate from the plans.  these were built for a 11.2' dia turbine IIRC. 

shoot me your email via PM and i'll pass them over. 

adam

[Jerryflyguy21]

PM sent.  [Thanks Btw! ]

It's kinda crazy how large the gap is on tower designs. The Bergey unit's w/ a 120ft tower don't have a stitch of concrete in them [granted you have normal soil.. not sandy/rocky/clay stuff].

The next place will have several yards of concrete.. 

Makes a guy wonder   

JFG

[Mary B]

Have you looked into just buying some off the shelf tower like rohn 25g? Used it goes for $50 per 10 feet, new about $120. Save all the headaches of building from scratch.

[Jerryflyguy21]

MaryAlana I'd looked at other tower designs but never priced them. The 'buy' price at $5/ft is attractive until you start factoring in freight to my location etc, at $12/ft + shipping it's alot more money than what I can build it for. Also, they require piles under them and based on the time of year that isn't going to happen until next spring which isn't an option either

I'm not scared of my design/numbers or building what i have...  again it is a simple tower used for measuring wind.. there is virtually no load on it other than 'itself'.

Thanks for the suggestion however!

JFG

[rossw]

I'm not scared of my design/numbers or building what i have...  again it is a simple tower used for measuring wind.. there is virtually no load on it other than 'itself'.

Just thinking out of the box for a moment....

Have you looked at buying or hiring one of several non-contact remote-reading wind profiling systems?
They don't require towers at all, and could measure at a number of heights - including probably far higher than you could practically build.

[Jerryflyguy21]

I had looked at a couple systems but wasn't convinced they were cost effective [I think one was an ultrasonic one and another used lasers or something, I didn't keep the links as it all seemed a bit over the top for my situation]. Do you have any names or links that you've seen?  Most of the ones I'd seen were in the 'many thousands', used for large site surveys [like a new Vestas field being set up etc].  Probably a bit outta my price range This one is gonna cost enough as it is 

Being as I now have all the Data logging stuff I'm pretty much locked into going this route, unless there was one I could get for less than $1000. Then I'd gift these to someone and just go that route but I don't think I should hold my breath 

JFG

[rossw]

Being as I now have all the Data logging stuff I'm pretty much locked into going this route

Yeah, well that certainly makes a difference.
I was thinking that the cost of equipment, tower, guys, groundworks, freight, etc etc  may have made a doppler/LIDAR type instrument "comparable" in cost, with the advantage of being able to readily move the latter to test multiple sites.

No, I don't have links or contacts for anything current. I had looked at it some time ago for another application but ended up going with a combination of commercial laser interferometer blocks and my own interfaces and processing platforms.

Like I said, just thinking "out of the box" as it were.

[Jerryflyguy21]

Thanks for posting it up Ross...   I like to think I'm a 'outta the box' thinker myself so I understand where your coming from

[Jerryflyguy21]

So I thought I'd post up a screen shot of my spread sheet and how I'm calculating my tower loading stuff.

Disclaimer--   DO NOT USE THIS DATA. I am not certifying that it is correct, usable or safe.  [<---  I think CYA is the proper acronym here     ]

I'm using an FOS of 4 in this run. I have the ability to go up to 10 stages. Some of the assumptions are that there is a guy set connected to the top of every section/stage. The gin pole is guyed down to the adjacent guy anchor point on each side of the GP.

Doing something as in-depth as this is certainly easier when you have excel!

BTW I'm not looking for anyone to run down the numbers or check my work... I'm not asking for engineering assistance, I'm just illustrating that I AM doing my due diligence to the best of my abilities.

JFG

[just-doug]

my first post was based on actually field experience with a 60 foot tilt up tower made of 2 inch water pipe.went very bad.i hope your tower project goes well and that you give us a up date when you do this as to how it went and what you would do different if you had to do it again.thanks Doug

[Jerryflyguy21]

Thanks Doug, can you offer any more info on how your tower was set up? Did you use 20ft sections of 2" sched 40 pipe?  guy wires [size/number]?  Weight on the end of the tower [as in turbine or..?]?  Length of Gin pole?  Per your last post it seems that as you were lifting it that it buckled and came down?  Did it buckle at a joint or?

I will post back once I've got my tower completed.

JFG

[SparWeb]

BTW I'm not looking for anyone to run down the numbers or check my work... I'm not asking for engineering assistance, I'm just illustrating that I AM doing my due diligence to the best of my abilities.

Then why post the chart?  

Re-run the numbers with 200 pounds static tension on the guy cables. 
There is no wind load on the pipe sections.  Admittedly small, but absolutely wrong to ignore them in a column structure.
At some point in your calculations the factor of safety gets multiplied in, but then it becomes hard to follow.
Usually it's easier to leave the FS out of the calculations until the end, then make a final conclusion about the FS you actually have.  It looks like you are repeating your target FS and trying to make the actual strength match up with a scaled-up applied stress, plus a reserve load capacity...  It's all fine for you who can see the formula used in the spreadsheet, but it's unclear on a summary page like this.


The stubby gin pole...  You've heard the objections already, but you still haven't changed it.  The pull-up angle is less than 17 degrees!!!

...And that's all from the engineering review comittee for today.
The bill is already in the mail.

[Mary B]

here is out of the box, weather balloon or some other type of lighter than air craft tethered at the desired height.

[klsmurf]

Mary
Sweet idea with the weather balloon. It crossed my mind last night after I read this thread.

[Jerryflyguy21]

Thanks Spar, I'd actually gone in and put the wind loads in after posting that screen shot up. They are small enough that it doesn't really even impact the whole picture.

BTW, I posted it up (1)to show that I wasn't just pulling numbers outta thin air & (2) To see if there was any interest by others in such a sheet. I'm on the fence as to if I should share it or not due to liability etc.

The only locations were the FOS is calculated in are labeled as such but for this screen shot I put it to FOS of 1.  The the gin pole was left short during one of my 'lets look at this' runs.  It's now back to the same radius as the anchors.
I left the pretension at 100lbs but that can get changed anytime.. it would mean upping the size of my tubing as it's currently spec'd they work well w/ the 100lbs pretension. Its not a big deal to try out higher pretensions and see what works.  I did read this morning that some people recommend pretensioning to 10% of the accepted load on the cable for my [now] 3/16" cable that would mean 370lbs, which seems excessive but..


MaryAlana, I'm not sure how I would measure the results for that and record the data over long time periods. The data recording system I've got here will take 1 record/sec for a year, use a 12v Car Battery w/ a solar charger and it's 100% stand alone w/ no need to babysit etc. How would a balloon improve on this?

JGF

[Mary B]

Just tossing out ideas. BTW Rohn makes a pound in base for the 25g tower series, no concrete needed.

[fabricator]

Have you checked on zoning ordinances in the area you plan to put the tower in?

[Jerryflyguy21]

As far as I know thus far I'm limited to a 200ft tower. At that point it is just a permit and it has to have the alternating red/white striping and lighting.
Still has to be confirmed conclusively.

JFG

[fabricator]

If there is an ordinance the building inspector will usually require a stamped engineering drawing from an engineer licensed in your state.

[ChrisOlson]

I don't expect that I will be putting up a 160ft Turbine/tower... no no..  I'm looking for data to prove that I DON'T have to put up a super tall tower. How do I conclusively prove this?  Measure it and present cold, hard numbers.

I read thru this thread trying to figure out why anyone would do this.  Nobody puts up MET towers to prove a commercial turbine needs to be on a shorter tower.  Nobody.

Nobody puts up 160 foot MET towers when SODAR, compared to wind maps of the region that have already been measured and determined on met towers, is a much more accurate and financially viable solution for predicting the output of a commercial machine on a particular site.  Nobody.

Have you ever erected a turbine or MET tower before?  No?  I thought so.

If you're getting into the wind power business you need to consult a professional.  Period.  This "project" (assuming it is a real project) has DISASTER stamped all over it.  Hiring a wind power pro to evaluate your site will cost you less than the hospital bills are going to cost when this contraption you think you're going to erect collapses and buries (hopefully only) you under a pile of junk.
--
Chris

[Jerryflyguy21]

I thought I'd replied earlier but I guess it didn't 'take'.

Fabricator- we do have inspectors but as far as I can tell it's not as stringent as say downtown in some city.   I've talked to a couple people and have been told that for what I'm wanting to do just to 'do it' rather than go through all the hassle of inspections etc.  I'm still trying to find out exactly what the local county would need. I wonder how many DIY builders on here have gone through the exercise of getting their install inspected and approved?

Chris, I've ready many of your posts in the past.  I'm over 1/2 way through skimming the 260+ pages of posts in the wind section of the site.  You used to fairly innovative but I have to say that over time you've become fairly negative?  I'm not sure what experience was the last straw but now your just as abrasive as the rest of them.  I'm think I will refrain from replying directly other than to point out two things. I looked at some SODAR installs...  ~$25-50K is a good start.  If I was to go the consulting route it would cost min of ~$10k to get started. I'm not located in the US so our wind data is not as complete or readily available. I noticed on www.secondwind.com that along side their SODAR installs they sell "GASP"   60M anemometer towers!?  And here I thought no-one did this [according to your sage remarks].  OH... and even better.. they are only worth $17000+/-  $500. [as far as I can tell that doesn't include the sensors or data recorder either]. Seems a bit steep compared to my unit.  Also for the record I've lowered my tower height requirements from 160ft to 100ft, if you HAD infact read the thread completely you'd know this.

I've got to say, the RE community [not just fieldlines.com] has a wonderful persona of being interested in promoting RE [wind] energy.. at least on the outside.  Once you get into actually doing things suddenly everyone is ultra negative.  As soon as anyone has the idea of stepping outside the norm of what others are doing, they get stomped on and sniped at with petty remarks. "As soon as someone comes up with an idea thats 'bigger/better/stronger' than mine I'm gonna make him out to be an idiot". I don't mind, I can take it but it certainly doesn't promote the community or incourage others to post ideas for fear of getting flamed. I certainly pondered the potential reaction of my posting prior to doing so [knowing it would incite some level of revolt due to it being a bit more ambitious than the average]. I feel like I'm back in highschool with all the bashing that occurs..  stomp on the guy who stands out.. keep 'em in line.. everyone conform or you'll be sorry, don't challenge me.. I'm the Alpha male here.. 

JFG [asbestos suit on]

[fabricator]

You know why Chris posted that reply? Because he has built and raised more towers than most on this forum, you are talking to a guy who has BTDT bought the Tee shirt.
You on the other hand have never built or raised a single tower, you wanted advice from experts, you got it, then you discount it, well, go ahead and put up your tower. It has become clear you really don't want advice you want yes men, on this forum we see you guys come and go regularly, so every one who has responded has seen it all before, good luck, and try not to kill any innocent bystanders.

[Rover]

Hello,

Some us of were mulling this over in IRC in a think outside the box situation. And I'm gonna open myself up for a lot of thrown mud on a stupid idea. I really don't mind, please flavor the mud first (little vanilla, maybe some chocolate).

I put forth a rather silly idea, rather than a tower to gather the data, why not a tethered weather balloon,  metering package somewhere along its tether.

As far as the negative responses to you on your approach, I'm not going to comment, I'm not an engineer. As far as there always being negative comments... sure there are, and there are positive to ( A whle lot of them, maybe not to this post but keep reading).

The funny thing is , you always have the ability to discontinue the discussion. I've done it on some of my posts when I  my idea was different than the curent norm (long time ago , strange derrick rigged tower with mounted solar panels) .

Basically at some point.. you just have to do what you think you should do. But don't blame someone for commenting if you put it out there.

Rover

[fabricator]

A balloon would be a non starter right from the gitgo, it would have to be tethered in at least three places like guy wires or it would be blown all over the sky, the forces on a balloon would tear it apart in short order.
If it were filled with helium it would expand during the day and go to the top of it's tether, at night it would shrink and put slack in the lines and be blown all over, it would no doubt come apart pretty quick.

[Jerryflyguy21]

Fabricator... I see it all now..  experience is tantamount to a licence to be belligerent. Make sense to me Nowhere in Chris's post did he elude to 'recommendations' based on his experience, it was more like peevish insult for 'whatever' reason. Inexperience in one area does not mean idiocy as a person, nor should a large resume of experience mean anyone is brilliant. In either case it's not nor should it be 'open season' on someone for an idea. Rebuttal based in fact or experience is another thing.. nothing of the sort was posted or presented.  I was not looking for YES MEN...  just open, honest discussion... without the 'knickers in a knot' petty remarks..   but that's probably expecting too much 

Rover I think for a longer term install it would be difficult to accomplish. Most of the weather [type] balloons I've seen wouldn't last due to the elements [UV etc] and would fail causing damage to sensors etc. As Fabricator pointed out, they would have to be restrained in position etc.. it might become more hassle than it's worth?


Anyway, I don't really see this thread going forward from where it currently stands. I'm done posting in it and discussion as it pertains to what I plan to do. It certainly isn't bringing the best out in the forum or people who post here. Therefore I'm going to let it drop. Should I ever need a specific answer to a specific problem I will post again but I'm done w/ general discussion.   I will post back when I'm done w/ my project and the findings/experiences I have along the way.

Have fun.. stay and play safe...   

JFG-->out

[ChrisOlson]

Chris, I've ready many of your posts in the past.  I'm over 1/2 way through skimming the 260+ pages of posts in the wind section of the site.  You used to fairly innovative but I have to say that over time you've become fairly negative?

Look - this whole thread is suspect.  I read you're putting up "commercial" turbine(s) "bigger than a 10 kW Bergey".  And you're going to do a wind site assessment yourself using (initially) a 160' bullwhip made from chain link fence tubing raised with a 30 foot gin to prove you don't need a tower that high for a real turbine.  That's REAL suspect information to ANYBODY who has worked with wind power systems any amount.

You're not putting "commercial" turbine(s) "bigger than a 10 kW Bergey" yourself.  You obviously don't have the experience to do it.  So either come clean with what the real story is here or you're wasting everybody's time by posting this to the Wind section of the forum, and it belongs in Newbies where far out stuff like this gets discussed all the time.
--
Chris

[Watt]

My personal experience with the board as a WHOLE.  FANTASTIC - including EVERYONE who posts, good or bad.  The good, I read on.  The bad, I choose not to read.

Thin skin....  Maybe.

All the emoticons available can't express typed words to be interpreted as an individual would normally speak in person to person dialog.  Body language etc ".

I have never met anyone on this board personally, I'd think, and can't say " you type just as you speak/express.  

Yes, off topic.  Or, is it.

[niall2]

erm....a bit off thread ...but  did,nt the Chinese use man lifting kites to spy on their opposing armies centuries ago ..a bit of wind measurement might have been an option ..... and they did,nt have micro sd cards or quad intel processors

if the local tree,s  have grown sideways over time in the prevailing wind.......the game just might be on...sadly ...thats what i,d go by

nothing wrong with new ways of measuring things though  







 

 

[DamonHD]

If we can't be civil I may have to lock this thread.

[Edited this para out as the temperature seems to have dropped a little!]

No one forces you to agree with all the comments (I have no view other than urging you to remain safe, lacking the experience in towers), but we can ask you to say nothing if you have nothing nice to say.

Rgds

Damon

[wooferhound]

A balloon would be a non starter right from the gitgo, it would have to be tethered in at least three places like guy wires or it would be blown all over the sky, the forces on a balloon would tear it apart in short order.
If it were filled with helium it would expand during the day and go to the top of it's tether, at night it would shrink and put slack in the lines and be blown all over, it would no doubt come apart pretty quick.

What about Advertising Blimps
I see them 200 feet over Car Lots all the time, and in the middle of the city
http://www.advertisingblimps.com/

[ChrisOlson]

What about Advertising Blimps

That's getting about as far out as raising a 160 foot tower with a 30 foot gin   

The dude said he's putting up "commercial" turbines "bigger than a 10 kW Bergey".  Anybody that puts up those kind of turbines had better be consulting with a pro.  And that includes a wind site assessment.  The pro has the equipment (and the training and experience) to do it right.

The facts are - and Newbies to wind power need to realize this - you cannot cut corners when you're strapping up 3,000+ lb turbines that are "bigger than a 10 kW Bergey".  If you try, you will find out what "there's always enough money to do it right the second time" means.
--
Chris