Companies in Texas engaged solely in the business of manufacturing, selling, or installing solar energy devices are exempted from the franchise tax. The franchise tax is Texas’s equivalent to a corporate tax. There is no ceiling on this exemption, so it is a substantial incentive for solar manufacturers.
For the purposes of this exemption, a solar energy device means "a system or series of mechanisms designed primarily to provide heating or cooling or to produce electrical or mechanical power by collecting and transferring solar-generated energy. The term includes a mechanical or chemical device that has the ability to store solar-generated energy for use in heating or cooling or in the production of power." Under this definition wind energy is also listed as an eligible technology.
Texas also offers a [http://www.dsireusa.org/incentives/incentive.cfm?Incentive_Code=TX04F&re... franchise tax deduction] for solar energy devices which also includes wind energy as an eligible technology.