Build Your Own Wind Turbine

Servicing workshop on a home built 2.4m wind turbine 10th October 2009.

This wind turbine was put up almost two years ago and this is the first time that it has been serviced,
ideally servicing should be done once a year.

The machine before we took it down

Specifications:
Off grid system
460 AH battery bank
24 Volt DC
2.5kw inverter charger
Solar PV 250w
Turbine Blades- Austrian larch
Turbine Frame- stainless steel
Mast 10m high

The site is in the Leitrim hills, it is overlooking Lough Allen and is well exposed.

First thing was to lower the turbine using the gin pole and small tirfor with 8mm wire rope.
The two side anchors are not level and this makes it tricky to operate the hinged mast. We had to stop the lowering a few times to slacken the guy wires and tension the gin pole ropes but it worked out fine.




 








First thing we noticed was one of the tail bolts was missing a nut and it had almost fallen out and the ply was starting to spread - it's important to use good quality ply and seal it well a new tail is in the making.







The blades are made from Austrian larch and painted with undercoat. They have stood up well with just the paint getting chipped along the leading edge and some green life growing at the roots. Sorry there are not more photos of the blades but they were in good shape and I forgot to take more photos.

The rectifiers are at the base of mast and the 9 ac wires running down the mast worked well with no twisting that we could see (another good argument against slip-rings). On the top of the mast we used a piece of plastic waste pipe, this worked very well as a bearing surface with very little sign of wear, it also makes the yawing nice and quiet.

Striping the machine revealed some scratches on the stator but it was just on the surface and there was no damage done to the coils thanks to the fiberglass mat. The reason for the scratches can be seen in the photos- the nickel plated magnets have started to rust. The reason being this machine was built using polyester resin and as you can see it is not that waterproof. We are going to clean up the disks as best we can and use a good two pack paint and hopefully get another few years out of them before we have to recast the rotors using vinylester resin and new magnets, this should solve the rust problem as the vinylester is waterproof.

Page 2