Several states in the US have encouraged extensive development of wind energy.
Investigations in California following the power crisis reported to the state legislature that because electricity systems must be kept in balance on a real time basis in order to maintain system reliability and because output from wind power is intermittent, variable and unpredictable, other dispatchable generating units must be kept immediately available to provide back up. These must be kept connected to the grid and running below peak capacity or in spinning reserve mode. These units incur costs which are part of the real cost of wind power generation.
A study during the 2006 California heat storm revealed that output from wind power significantly decreased as peak demand increased, due to greater air conditioning and other demands that stem from high temperatures.
A sudden drop in wind speeds in Texas in December 2009 almost resulted in blackouts in western parts of the State.
The US Department of Energy (DoE) has published a comprehensive report listing the steps to implement in order to develop wind energy. The programme aims at installing a total of 100 MW in each of sixteen states by 2010, recently raised to 30 states. Three primary targets are identified:
- Technology characterisation and data collection
- Tools and methods of development
- Applications and implementation
A substantial research and development programme is needed to examine both high and low wind speed turbines, including the deployment of smaller wind systems in distributed settings. The thrust of this structured plan is that the DoE wishes to assess the future potential for wind and to move progressively towards a manageable system; in small regional units rather than large wind carpets like the European systems.