Generally, you can expect a power loss of 10% to 15% of the total load you are running. If your microwave uses 1000 Watts, your battery is actually supplying roughly 1150 Watts. An inverter consumes energy in two ways: through conversion inefficiency and standby (idle) power draw. They generate heat while changing Direct Current (DC) from your batteries into. Battery current draw depends on three primary variables: Inverter Power Rating (Watts): Higher-wattage inverters demand more current. Battery Voltage (Volts): A 24V battery will draw half the current of a 12V system for the same power output. Formula: AC Output = DC Input × (Efficiency/100) × (1 - Margin/100).