Raja Azlan Shah FJ:

The respondents ("the Board") had contracted to supply electricity to the appellants. By mistake, it had considerably undercharged the appellants to the amount of $84,624.01 and successfully claimed that amount from them. The learned trial Judge held that the Board was not estopped from claiming that amount although the appellants had utilised the accounts rendered by the Board for the purpose of costing their products. To have admitted the estoppel, so the learned Judge held, would have had the effect of nullifying the statutory provisions of the Electricity Act, 1949 (Revised - 1973).

This is an appeal against that decision.

Before stating the facts on which this appeal turns, and the contentions of Counsel, it seems to be convenient to refer to the relevant statutory provisions of the Electricity Act, 1949 (Revised - 1973) and the Electricity (Board Supplies) Rules, 1949, (LN 515/49; amended LN 235/64).

The Board is a corporate body constituted under s. 3 of the Act, and is accordingly under a statutory duty to secure the supply of energy at reasonable prices (s. 15), to enter into contracts with any person upon such terms and conditions as it may