i) Tariff: The rate at which a consumer is charged for the consumption of electricity is called as tariff.
The amount of money framed by the supplier for the supply of electrical energy to various types of consumers in known as an electricity tariff. In other words, the tariff is the methods of charging a consumer for consuming electric power. The tariff covers the total cost of producing and supplying electric energy plus a reasonable profit.
ii) Fuel surcharge: It is amount that utilities apply on bills based on varying price of fuel or Coal. The price of coal or fuel changes every month based on demand and supply of coal and thus cost of producing electricity changes accordingly. The electricity generation companies pass on this cost to distribution companies who there by pass it on to consumers.
iii) Electricity Duty: Electricity duty is charged on consumption and it is nothing but tax on electricity. It is mostly a rate that is applicable per unit of electricity consumed. In some states it is also applied as percentage of total charges (electricity usage + fixed charges) and in some states both are applicable.
iv) Connected load: It is the total wattage of all appliances which are used by the consumer on his sanctioned connection.