The growth of wind energy in Texas between 2006 and 2009 resulted in transmission congestion and the eastern part of the state was unable to get any of this energy. The amount of wind power that was being generated was too much for the power demand centers to handle. As a result, any excess wind energy had to be curtailed.
In an effort to stem the constraints related to wind energy transmission, CREZ was established in 2008 by the Public Utilities Commission of Texas and featured five zones that had the highest wind potential. In addition, transmission expansion projects were authorized to allow the five zones to receive over 18,000 MW of wind power.
Competitive Renewable Energy Zones (CREZ) has resulted in a drastic decrease in the curtailment of wind generation in Texas since 20011. The CREZ program has been very instrumental in allowing more wind power to flow to areas in the state that have a higher demand for electricity.