Maximum Demand Tariffs

The total demand for electricity at any instant is the sum of the individual demands of 1.7 million customers. Typically daytime demand is higher than at night; weekday demand higher than at weekends and winter demand much higher than in summer. Because electricity cannot be stored there must be sufficient generation, transmission and distribution capacity to meet the highest demand.

For these reasons most tariffs for larger users are designed to encourage customers to control electricity demand at daytime peaks. For example, night rate electricity encourages the transfer of daytime usage to the night period and maximum demand tariffs are structured to reflect not only the amount and rate of electricity use but also the time of day it is used.

Maximum Demand Tariffs are available at different voltage levels

The Low-Voltage MD Tariff
This MD tariff is suited to customers who are supplied at 400/230V and whose Maximum Import Capacity (MIC) is 50kVA or more.