WHILE LOOKING AROUND B&Q in Limerick, I discovered the retail chain has stopped selling its rooftop wind turbines after a study showed thhey performed badly in built-up areas. That's pretty much the same conclusion made by colleague Liam Noonan who has always. urged me to complete a months-long site survey before erecting a small wind turbine on my property. A combination of low wind speeds in my specific estate, turbulence (a wind tunnel effect) and the presence of too many nearby buildings with border walls mean that wind turbines in urban areas turn out to have far lower generating capacity than they promise. It is also very easy to find negative comments on Irish discussion boards about the B&Q turbines. Some analysts think it wold take customers more than 15 years to recoup the EUR 2300 cost of the turbines. You could achieve better savings faster by cuting back on the number of times you boiled hot water in your home. The big problem in Ireland is the gusty wind conditions in the country. Those gusts contribute to a lot of wear and tear. Regular periods of calm wind conditions produce no electricity. Since performance varies considerably, some rooftop microturbines fail to generate enough electricity to power the turbine's own electronics.