Thousands of wind turbines in the US are sitting idle or failing to meet their full generating capacity because of a shortage of power lines able to transmit their electricity to the rest of the grid.

The issue of transmission capacity will be high up the agenda as 10,000 wind power industry executives descend this week on Houston, Texas, where the shortage of power lines is hampering the state's alternative energy plans. The problem is particularly acute in Texas because of the speed with which it has grown its wind power industry, two years ago surpassing California as the state with the most capacity. The solutions devised in Texas could form a model for the future of the industry in the US and elsewhere, as energy companies look beyond fossil fuels for cheaper and greener sources of power.

A proposal for $6.4bn of new power lines linking new wind farms with the state's public electricity grid, whose cost will be borne mainly by consumers, is proving politically controversial. Wind farm developers are examining building their own private lines.

"Delivering electricity is a very complex system, and wind adds another level of complexity," Jone-Ling Wang, managing director of global power for Cambridge Energy Research Associates, told the Houston Chronicle before yesterday's conference. "In Texas, the success of wind means the challenges will be great, too." In a moment of high symbolism, the American Wind Energy Association's annual Wind Power conference this year will for the first time be held in Houston, capital of the US oil industry.

State laws requiring alternative energy options for consumers, as well as federal tax breaks, vast open land and high winds have combined to make the Texas panhandle one of the fastest-growing areas of wind farm development in the world.

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