( 1 ) IN this appeal, the appellants, namely, the Union of India, the Joint Secretary to the Government of India, Ministry of Steel, Mines and Coal (Department of Mines) and the Controller of Aluminium have challenged the propriety of the judgment of a learned Judge of this Court whereby the learned Judge made absolute the Rule Nisi issued on the application of Hindustan Aluminium Corporation Limited, hereinafter referred to as HINDALCO, and one of its share-holders, under Article 226 of the Constitution. In the writ application, the respondent HINDALCO challenged the propriety and legality of five orders of the Central Government, all dated Oct. 4. 1979 under the Aluminium Control Order, 1970 passed under Section 3 ef the Essential Commodities Act, 1955. The legality and constitutional validity of the provisions of Clauses 4a and 4b of the Aluminium Control Order were also challenged in the writ application.

( 2 ) AT all material times HINDALCO carried and still carries on the business of producing and/or manufacturing aluminium. It owns and operates an aluminium plant at Renukoot, in the district of Mirzapur, within the State of Uttar Pradesh. It produces and/or manufactures the following: (a) aluminium and alloy ingots, billets and wire bars, (b) aluminium wire rods known as 'properzi' rods, (c) aluminium rolled products in various shapes, (d) aluminium extrusions in various shapes and types of sections.

( 3 ) BESIDES HINDALCO, there are three other companies which produce and/or manufacture aluminium and its products. These companies are Bharat Aluminium Company Limited, which is a Central Government company the Madras Aluminium Company Ltd. , and Indian Aluminium Company Ltd. , here inafter referred to as BALCO, MALCO and INDALCO respectively.

( 4 ) THE production of aluminium in India is of vital importance and it is essential for the growth, development and maintenance of the economy. The Central Government by virtue of its power under Clause (xi) of Section 2 of the Essential Commodities Act, 1955 declared aluminium to be an essential commodity by a notification dated June 29, 1957.

( 5 ) THE demand for aluminium has been rising because of massive investment in generation, transmission and distribution of electricity, particularly in rural electrification programme. The demand for commercial grade aluminium has also been rising principally on account of compelling need for saving energy, aluminium being a very light metal with high heat conductivity. The production of aluminium in the country, however, has not been able to keep pace with the increase in demand although the present installed capacity is adequate to meet the current demand. The shortfall in production is due to inadequate availability of power to aluminium smelters. In the circumstances, the Central Government has been compelled to arrange import of aluminium since Sept 1977. Imports are now being made through the Minerals and Metals Trading Corporation (hereinafter called MMTC ).

( 6 ) IN order to combat inflation in the price of aluminium the Central Government by a notification dated May 20, 1970, issued under Section 3 of the Essential Commodities Act passed the Aluminium Control Order, 1970 (hereinafter referred to as the Control Order) for the availability of aluminium and its products at fair prices and for regulating production, supply and distribution thereof. The Control Order was amended from time to time.

( 7 ) THE consumption of power for production of one metric tonne of aluminium varies in different smelters of country under optimum conditions. One paise variation in the power tariff rate leads to a variation of about, Rs. 170/-per tonne (according to HINDALCO Rs. l80/- per tonne) in the cost of production of aluminium. Different State Electricity Boards charge different power tariff rates to the smelters catered to by them. The cost of production of aluminium per metric tonne, therefore, varies widely in different sm