JUDGMENT

CHINNAPPA REDDY, J. :— These appeals preferred by the Kerala State Electricity Board raise the question of the extent of the authority of the Board to increase the Electricity Tariff under the Electricity (Supply) Act. The upward revision of tariff made by the Board in 1980, 1982 and 1984 was successfully challenged in the Kerala High Court. The first two revisions were struck down by a Full Bench of three judges by a majority of two to one and, later, all three revisions were struck down by a Full Bench of five judges by a majority of four to one. The principal ground of challenge and that which was accepted by the High Court was that the Kerala State Electricity Board acted outside its statutory authority by formulating a price structure intended to yield sufficient revenue to off set not merely the expenditure properly chargeable to the revenue account for the year as contemplated by S. 59 of the Act but also expenditure not so properly chargeable. Had S. 59 been strictly followed and had items of expenditure not chargeable to the revenue account for the year been excluded, the revised tariff would have resulted in the generation of a surplus far beyond the contemplati