4. Levy of Electricity Duty on consumes.

Every consumer belonging to any of the classes specified in column (2) of the Schedule shall pay every month to the Government in the prescribed manner a duty calculated at the rate specified against that class in column (3) thereof: Provided that in cases where the supply of energy to a consumer is regulated by an agreement entered into between the Government or the lisensee and the consumer it shall be competent for the Government either to reduce the rate at which duty is leviable on such consumer or to exempt such consumer from payment of duty under this section subject to such terms and conditions as may be imposed by the Government.