P. Naveen Rao, J.

1. In all the writ petitions disposed of by this common order, petitioners own captive power generating plants. Petitioners challenge constitutional validity of Section 3-B of Andhra Pradesh Electricity Duty Act, 1939 (for short Act, 1939) as introduced vide amendment Act No. 14 of 2003. This provision vests power in the Government to impose duty at the rate of 0.25 paise per unit on consumption of electric energy by captive generating units.

2. All the petitioners are involved in industrial activity such as manufacture/production/storage etc., of various products that require high volume of uninterrupted electricity energy. They are enrolled as consumers with State Public Sector power Utilities (for short, Power Utilities). The Power Utilities classify consumers as Low Tension (LT) and High Tension (HT) consumers depending on the volume of electricity supplied. Petitioners are HT consumers. For the sake of convenience, the facts as narrated in W.P.No.6769 of 2004 are taken.

3. Petitioner is a company incorporated under the Companies Act and is engaged in manufacture of synthetic yarn at its factories at Sadshivpet, Medak District (forming part of State of