A wind energy light installation near Munich, Germany. Peter Kneffel/EPA Between 4:30 and 6 am on November 8, on a blustery Sunday in Spain, wind turbines supplied a of the electricity flowing through the country's power grid. A similar on October 28, when 5,667 megawatts of wind generation supplied an unprecedented 25 per cent of the state's electricity load in the pre-dawn hours around 3 am. The ability to generate lots of juice when most people, even the late-dining Spaniards, are in bed, is not necessarily one of wind power's greatest strengths. Rather more usefully, the Texas turbines achieved a record 6,223 megawatts of output, representing nearly 70 per cent of the state's installed wind capacity of 8,916 megawatts, at 8:30 pm on October 28, a Wednesday. At that time, most Texans would have been glued to prime-time television, so the wind vanes supplied a lower percentage of the overall load than in the wee hours. Nevertheless, the double record scored that day in the Lone Star state is significant, and could herald further progress towards the US government goal of generating . One reason for that is that Texas, the jurisdiction with the world's sixth highest installed wind capacity, is finally moving to unblock power flows through its congested grid. A new 345 kilovolt power line called the can now move an extra 950mw of electricity from windy but sparsely populated West Texas to large cities such as Dallas and San Antonio. Before the line was installed, the Texas grid could not handle all the power output from the wind farms on stormy days. It is still a challenge for grid operators to keep power supply and demand in balance as the output from wind turbines fluctuates with passing weather fronts. In February 2007, the (ERCOT) cut off power to industrial customers when the wind suddenly stopped blowing and the grid operator was unable to bring other power stations on line fast enough. ERCOT has since improved the reliability of its wind forcasts, and new wind farms have been built along the Texas coast to offset the volatility of the West Texas power supply. Unlike real winds, the winds of change are always blowing.