K. Vinod Chandran, CJ.—The petitioners are industries engaged in the manufacture of sugar, who are generating power, in-house for captive consumption.

2. The petitioners are aggrieved with the provision made for levying duty under the Bihar Electricity Duty Act, 1948, on the ‘value of energy’ as defined by an amendment; which amendment has also been made retrospectively with effect from 17.10.2002 and also with the provision for validation; to nullify the effect of the judgment in Bihar Sugarcane Mills Association and Ors. vs. The State of Bihar and Ors; 2009 (4) PLJR 460.

3. The levy, as originally imposed under Section 3 of the Bihar Electricity Duty Act, 1948 was challenged on the ground of legislative incompetence; since it is in the nature of a levy on production clearly coming within Entry 84 of the 7th Schedule of the Constitution of India, and the exemptions to certain establishments, under sub-section (2) of Section 3 making the levy discriminatory. A Division Bench of this Court negatived the challenge based on constitutionality, or the lack of it by a decision reported in Indian Aluminium Co. vs. State of Bihar; 1992 (1) PLJR 55. The petitioners were all paying the duty, for the electricity generated, at the rate of Rs. 2 paise per unit of energy. A notification was issued under Section 3(1) by the Government increasing the levy to Rs. 4 paise per unit for electrical energy consumed or sold for the purpose of irrigation and 6 % of the ‘value of energy’ for electrical energy consumed or sold for any other purpose than irrigation; by S.O. 137 dated 21.10.2002. S.O. 14 dated 04.03.2005 made a further entry to the Schedule, including the category of consumption of electrical energy generated by captive DG sets/captive power plants, for whom the rate of duty was provided at 6% of the ‘value of energy’, which shall be equivalent to the energy tariff as fixed by the Bihar State Electricity Board, (for brevity, BSEB).

4. The said amendment & notification were challenged by a batch of writ petitions in which they were held to be unconstitutional for reason of there being available no guideline in the Statute, to ascertain, in which cases the duty would be payable, calculated on the basis of the energy consumed or sold and there existing no guideline for determining the ‘value of energy’ as provided for in the notifications of 2002 and 2005. The State, after the decision in Bihar Sugarcane Mills Association (supra) brought in amendments with retrospective effect and a validation clause specifically providing a definition for ‘value of energy’. The said amendment brought in by the Bihar Finance Act, 2012 is challenged before us in the batch of writ petitions.

5. It is undisputed that the amendment and the challenge raised is confined to the duty levied prior to 14.01.2011. On 14.01.2011 S.O. 1 was issued exempting from payment of electricity duty, electrical energy generated by generators or captive plants, so generated solely for self-consumption. The amendment of 2012, was to ensure that the amounts paid up by the different industries, as per S.O. 14, who were captive consumers of electricity generated by them, remains in the coffers of the State without being refunded, on the provisions being struck down in the Bihar Sugarcane Mills Association (supra).

6. Learned Senior Counsel Sri Y.V. Giri, argued for the petitioners and elaborately referred to the judgment in Bihar Sugarcane Mills Association (supra) to contend that the defect, for reason of which the notification was declared ultravires by this Court, has not been rectified even now. It is emphasized that the petitioners are a separate class from the normal consumers who pay tariff per unit as determined by the BSEB; which is the licensee of the State Government. The tariff is determined based on a number of factors including loss on transmission, none of which applies to the petitioners. The Division Bench, on the earlier occasion found that the petitioners are a separate