Off-peak electricity is energy supplied at a lower tariff during specified times, often through a controlled-load connection for appliances such as electric hot-water systems. The timing and price vary between states, distributors, retailers and tariff types, and off-peak periods are not always overnight. Check your bill or ask your retailer which appliances use the tariff and when it applies. It may reduce costs if suitable usage is shifted to those periods, but compare the full tariff rates, supply charge and any required meter changes before switching.