AWEA works on the concept of the Production Tax Credit (PTC) under the Energy Policy Act of 1992, gaining bipartisan backing from Sen. Chuck Grassley (R-Iowa) and Rep. Philip Sharp (D-Ind.). The PTC rewards high-quality, long-lasting products, which entices investors and triggers development. However, the PTC expires several times between 1999 and 2003. This uncertain business environment causes several boom and bust cycles.