Used Wind Generator:
Is It WORTH the Investment?

Unlike used cars, used wind generators have fewer checking points. Nevertheless, they have several moving parts that are likely to get damaged or worn out after long use, being exposed as they are, to the elements all the while. In case you intend to bargain for a small-wind machine offered at a throw away price, beware of it. Your best bet would be to stay away from such deals as these machines have a limited life cycle after which they are sold as scarp. Besides, you can build a new small home turbine yourself for little less than $100 – so why go for a used one. Also perilous are big turbines that have been dismantled from Wind Parks and sold at ”half the price”. Ninety to one, they have been replaced by the owner/owners after completion of their full working life and are just ‘no good’.

If however, you are really keen on buying a medium sized used wind turbine, think in terms of rebuilding it first and then installing it. Of course, you should be thoroughly familiar with all the components in a turbine first and then attempt to refurbish it.

A wind turbine consists of a permanent magnet electric motor that works as a generator. Otherwise, it has a mild steel shaft held by a pair of bushes or bearings and is coupled to a generator fixed within the housing through helical gears. A hub with blades properly balanced on it and fixed to the shaft helps to run the system when facing strong wind current. A turbine also has a tail attached to it which keeps the unit facing towards the prevailing wind current. As the blades rotate, the shaft rotates and when the shaft rotates, the motor or the generator rotates too, producing electric current. So, when you are refurbishing a wind turbine, you are advised to dismantle the unit and do as follows.

§         Throw away the bushes or bearings and replace them with the maker’s original spares. In case the manufacturer can not be traced, take the shaft or the spindle to a reputed hardware store and seek the help of the assistant there who may provide you with the right kind of bushes or bearings. 

§         Check the helical gears and see that they are meshing well. If the gears are worn out, they will either get jammed or would tend to ‘slip’, affecting the functioning of the turbine. Once again, try to contact the manufacturer for original set of gears or visit the hardware store to pick up identical set of gears. Since the gears are also held in position by bushes, you would have to replace them too.

§         Remove the armature from the motor and test it for leakage at high volt. Minor leakages would not be revealed by testing at lower voltage. Check the insulation and re-insulate it properly which may ‘cure’ minor current leak.

§         Check all metal parts, body casting and small components for metal fatigue Ideally, you could have taken the help of an electronic ‘Crack Detector’ to see if any of the components has developed crack or chink during earlier operation.

§         Replace all bolts, nuts and fasteners even if they look alright.

§         Sandblast all components (except the bearings) then prime and paint them with a durable kind of paint to withstand the ravages of nature all through the years that the turbine is required to give service.

§         Rebuild the blades or order for replacement, if available. Repaint the blades with automotive or marine grade finishes if you are not using replacement blades.

§         Pay special attention to the used tower if you have also acquired the tower along with the turbine. But remember that it is the turbine’s ‘Achilles’ Heel’ that is a constant source of worries and, therefore, should be thoroughly checked for visible defects or structural fatigue.