World wind capacity increased by 1500 MW in 1997, or by nearly 25%. The total is now around 7600 MW -- close to that of geothermal capacity for electricity generation. Wind capacity is doubling every three-and-a-half years and if the trend continues there will be around 15,000 MW by the end of 2000 (graph). In Europe, Spain recorded the strongest growth in 1997, doubling capacity. It overtook the Netherlands and Britain, and moved into third place behind Germany and Denmark. Germany recorded a 35% increase. In America net capacity declined 22 MW to 1592 MW and the number of turbines in service slipped to about 13,500. The removal of some 280 turbines in the Tehachapi Pass last year offset small repowerings to cause a net decline in installed capacity in California, the sixth year in a row of decline in the state. Outside California net wind capacity increased by about 8 MW, including the 6 MW of Zond turbines installed in Vermont in 1996 that became operational in 1997. In Asia, China continues to tantalise as the world's biggest potential market, but wind development is still in the form of one-off projects only. Nonetheless, China was one of wind's fastest growing markets in 1997. India's political chaos and soaring interest rates kept the wind market in limbo all year, though the long term outlook remains good.