25/08/2026
Maximum Demand vs Time-of-Use Tariffs
Not all electricity tariffs work the same way.
Some customers are charged mainly for the energy used, “measured in kWh”.
Others are also charged for maximum demand, “the highest power drawn at one point in the month, measured in kVA or kW.”
Then there are time-of-use tariffs, where electricity costs more during peak periods and less during off-peak periods.
This matters when designing solar.
A solar system that reduces daytime energy may help with kWh savings.
A battery system may help shift usage away from expensive peak periods.
But if your bill includes maximum demand charges, the system also needs to consider your peak loads, not just your total monthly consumption.
Before installing solar, understand your tariff first.
The right design depends on how you are charged: Energy, demand, time-of-use, or a combination of all three.