Repayment of grant of electric energy

of electric energy at conc~sional rates] shall ordinarily be that an amount equal to the sum paid or to the value of the graot or concession as fixed at the time when it is made shall bc repaid to the State Government at the close of a fixed term of years if within that term the industrial business or enterprise shall be shown to be paying interest or a dividend upon the capital invested in excess of such rate as the State Government may fix.