JUDGMENT

G.N. RAY, J.

(1) LEAVE granted in all these five special leave petitions. Heard learned counsel for the parties and the appeals are disposed of by a common judgment in view of the fact that in all these matters common question of law and fact arise.

(2) M.R.F. Limited is the respondent in appeal arising out of Special Leave Petition No. 16265 of 1991. The said M.R.F. Limited (hereinafter referred to as the Company) is engaged in manufacturing automobile tubes, tread rubber etc. and the said Company entered into an agreement with the Kerala State Electricity Board (hereinafter referred to as the Board) for supply of electricity to the factory of the said Company. The agreement contained a provision for payment of power and energy supplied to the Company by the Board within 15 days from the date of the receipt of the invoice by the consumer, namely, the Company. It was further provided for in the agreement that in default of payment within the stipulated time, the payment was to be made with interest @ 18 per annum or at such other percentage as would be fixed by the Board from time to time.

(3) THE Board revised the tariffs for the electricity supplied