| Not to be confused with free-standing mini wind turbines, which are 
			dealt with separately. Micro 
			wind turbines have been used successfully for many years in 
			applications such as boats, caravans and other places where no fixed 
			electrical supply is available.  These generate DC power 
			suitable for battery charging and the majority of portable 
			appliances and tend to be located in windy areas, free from 
			obstructions.  Recently attempts have been made to apply the 
			same technology with turbines mounted on buildings (to save the cost 
			of a free-standing tower) and using inverters to convert the DC to 
			AC power suitable for connection to the consumer unit in a home 
			(grid-parallel operation).  In this configuration the turbines 
			are subject to the very turbulent wind conditions and low wind 
			speeds typical of the urban environment, so that the turbines 
			continually "hunt" to find what little wind is available and do not 
			stabilise for long enough to produce a great deal of useful power.  
			In addition the requirement for power electronics to synchronise 
			with the mains supply has led to additional inefficiencies, so much 
			so that, in some cases, the inverter losses exceed the useful 
			electricity generated. The force of the wind on the turbine 
			causes considerable noise and vibration which can be amplified by 
			the structure and, in a few cases, the force exerted by the turbine 
			on the building to which it is attached has led to structural damage 
			to the wall.  One major supplier recently recalled their 
			products after components became detached in strong winds. Monitored trials to date have 
			demonstrated poor performance in urban conditions.  Rural 
			locations with free-standing products may perform better. |