Secondhand Proven 2.5kW 48V turbine

Posted on 02/04/2017 by hugh

I have been asked to mention a 2.5kW Proven wind turbine (nowadays “KingspanWind”) that is available factory reconditioned.  I installed this turbine in the Highlands in summer of 2004, charging a 48V battery as part of a hybrid power system for a private client.  It caused no bother and was given no further attention, until it burned out last year.  I have not been shown any pictures of the damage but I understand this failure was attributed to a lightning strike, and was covered by insurance so the client got a new turbine under his insurance.  The original turbine has been factory reconditioned but is now for sale to cover the cost of this reconditioning.  It comes with blades but no tower.  It’s a solidly built machine that is good for at least another 12 years service, or more if the lightning will stay away.  Get in touch and I will send details of how to contact the seller as usual.

Tech specs 2.5kW

Posted in stuff on offer | 8 Comments

More secondhand stuff

Posted on 08/03/2017 by hugh

People often let me know when they have secondhand stuff that might be of interest, and I am very happy to mention it here.  Often it finds a good home.  I got two emails today.

Neil on Barra has three windyboy 3800 inverters that he can’t use.  Also a 10kW Westwind load controller.  If you are interested then post a comment or email me and I will put you in touch.

Simon in the Highlands has a secondhand hydro turbine that can do 10kW at 330 l/sec on 8.3m head.  An Evans Engineering R&D model.   It’s a bit rusty in places but serviceable.  “It is all dismantled and ready to go to a good home (or the scrap-yard).  Would suit somewhere on a big river with a clean intake.”

Again I can put interested parties in touch.

Posted in stuff on offer | 2 Comments

Still time to get a place on the Scoraig Workshop 15th April

Posted on 28/02/2017 by hugh

I will be holding a wind turbine building workshop here at my home on Scoraig from 15th-22nd April 2017.   Kostas Latoufis will be helping me this year.  Most of the places are taken but there is just room for one more, maybe two if I get a cancellation.  Please get in touch soon if you are interested in details of this event.  Photos of last year’s workshop are here.

The happy group

Posted in construction, courses, Notices, Scoraig | Leave a comment

Have we got our priorities right?

Posted on 19/02/2017 by hugh

I can’t understand a society where people are pleased and proud to own a fancy car that will never pay for itself, and pollutes the planet, but hang their heads in shame if their wind turbine does not pay for itself and make them money. Why not own a wind turbine and be proud of using renewable energy? Why does it have to also pay before it’s a socially acceptable thing to own??

Posted in UK small wind scene | 4 Comments

Fixing a 2F turbine on Scoraig

Posted on 05/02/2017 by hugh

The other day I had to take this 2F windmill down because it had stopped working. Turning slowly as if on the brake.  It’s a few years old and I thought most likely the flexible wiring inside the tower had got twisted up a bit and somehow shorted out, although the wires did not look that bad a ground level.

I was pretty shocked when I saw it close up, because the plywood had somehow got shattered at the front.  Birch plywood is very strong, but I suppose I was pushing it a bit to use 9mm ply here.  It’s not the oldest 2F on Scoraig using that plywood but it definitely taught me something.  Always more to learn!

I replaced the 9mm with 12mm birch.  I figured out a quick way to lay out the screw holes in the plywood so they are neat and symmetrical, and avoid the bolt holes for the mounting studs.  I used a cardboard template that matches the shape of the contact area between blade and ply. (Click to see larger images.)

Punching through the dots on the cardboard gave me my hole centres for drilling.  Next I went looking for the shorted wiring.  But I found to my horror that the alternator was “braked” even when totally disconnected from the wiring, so the short was internal.  Maybe I needed to make a new stator?

First I set to work to find the location of the short.  I used a battery, a magnet and a photo that I miraculously found of the stator before it was cast (back in 2013).  

Passing current through the coils between each pair of wires gives rise to a pattern of attraction and repulsion of the magnet in the winding that reveals where the current is going.  (Usually this will be “push, pull, nothing, push, pull, nothing, push, pull, nothing.”)  One pair of wires gave rise to a very strong field in just one coil and the photo revealed where the short must be between the output wire off a neighbouring coil and a series connection from that coil to the next.

The fact that it was a fault on an incoming wire meant I could simply cut that wire and make a new incoming connection to the first coil in phase A where the wire comes close to the surface of the casting to enter the coil.  So there was not too much digging around to do in the resin (using a drill and a gouge).

That was pretty lucky, and a quick solder joint had it all sorted out.

Balanced the blades, greased the bearings, untwisted the tower wires with a cordless drill and got the machine back into action after a relatively painless repair considering how much worse it could have been!

Not a breath of wind of course.

Posted in construction, ferrite magnets, my own projects, Scoraig | 2 Comments

Wind turbine workshop in North Carolina, USA

Posted on 28/01/2017 by hugh

Handy Village Institute, 5840 Jewell Road, Graham, NC 27253 are hosting a wind turbine building workshop with Dan Bartmann of Otherpower March 20 – 25, 2017.

Posted in construction, courses | 1 Comment

New blades capture 99% of next to no power in the city

Posted on 19/01/2017 by hugh

Screen Shot 2017-01-19 at 13.54.23

An article has just come out in Engineering and Technology  describing how new super-efficient blades are going to make it viable to put wind turbines in the city.

“Small wind turbines (like the one pictured above) are often installed in urban and semi-urban areas. However, these locations are challenging as they require turbines that work at variable, often low, wind speeds while running smoothly and producing little noise. These conditions directly affect the technical requirements for wind turbine generators.”

This shows a profound misundertanding of the problem.  The reason why small wind turbines do not work in the city is not for lack of clever gimmicks such as ducting shrouds and fancy analysis. The reason is that there is hardly any energy there to capture.  Improving the efficiency is not the solution.  Capturing a higher % of next-to-nothing will still produce next-to-nothing.

This sort of article is misleading because it suggests that the reason why small wind turbines have not worked in the urban environment is lack of development of the technology.  Actually the reason is that this is the wrong application of the technology.  The technology is mature but in order to work it needs a proper wind resource.  This is not available in the city.  This article with its apparent engineering background lends legitimacy to misinformed people who buy and sell equipment that purports to usefully generate power in the city.  This is a waste of resources that also gives renewable energy a bad name.

Posted in Rooftop madness, UK small wind scene | 2 Comments

Secondhand wind turbine stuff

Posted on 13/01/2017 by hugh

Joff in Cornwall still has some secondhand stuff available.  I posted about this in 2014 here.  Some of that excellent stuff remains and he is keen to give it to a good home:

A couple of years ago, with your help I did manage to sell a few parts of my broken Eoltec turbine.  So thanks for your help with that.   Time has passed,  the financial loss is more distant, and I’ve been lazy about shifting the remaining parts. 

But now  it’s time to get rid of the rest.  Obviously demand is not high,  but the parts may be of some use to somebody and I’m not asking for any money.

What I still have left is;   a 12m galvanised tower,   2  Aurora invertors and various bits of switch gear and a transformer.

I’d be grateful if you could put the word around again.
regards,
Joff

Contact me or comment here and I will pass your enquiry on to Joff.

Posted in stuff on offer | 3 Comments

Workshop selfie video winding a coil

Posted on 11/01/2017 by hugh

I don’t put enough of the stuff that goes on in my own workshop onto this blog so here is a workshop session where I am winding a coil for a repair for a big machine, and I talk through the process a bit as I go.

 

Posted in construction, my own projects, Video links | 3 Comments

Eolocal video

Posted on 28/12/2016 by hugh

Here is a nice video from Eolocal in Argentina:

 

Posted in Video links | Leave a comment