Business for small wind turbines grew by 78% in 2008 according to the American Wind Energy Association (AWEA).  A new 30% tax credit in the federal economic stimulus bill will expand the currently booming market. Approximately 10,500 small turbines were installed in America last year which is about half of the world's total, costing $77 million.  A typical home windmill is used in conjunction with electricity from local utilities.  When wind is light, electricity comes from the utility company; high winds generate excess power which is sent back to the grid.  Owning a small windmill system for a home costs about $40,000 and would take up to 15 years to pay for themselves.  Zoning restrictions and objections from neighbors can pose obstacles.