Batteries, UPS & Solar
Every batteries, ups & solar calculator on CalcEngines — unit converters, derived indices and interpretive tools, each with its formula, a worked example and the reference intervals it is judged against.
7 calculators in this section
- Battery Charging Time CalculatorHow long a battery takes to charge from its capacity, the charger's current or power and the state of charge you start from — including the slow constant-voltage tail at the end.
- Battery Life CalculatorHow long a battery will run a load: from its capacity in mAh, Ah or Wh, the load current or power, how deeply you will discharge it and Peukert's exponent — with a duty-cycle option for devices that sleep most of the time.
- Inverter / UPS Size Calculator (VA)Add up to six appliances, mark the ones with a motor, and get the running watts, the VA the inverter must supply, the starting surge and the next standard inverter size up.
- Inverter Battery Backup Time CalculatorHow many hours your inverter will run on its battery: from the bank's Ah and voltage, the usable depth of discharge for your chemistry, the inverter's efficiency and the load in watts.
- Solar Battery Size CalculatorThe battery bank an off-grid or backup system needs: from the daily load in watt-hours, the days of autonomy you want, the usable depth of discharge, the bank voltage and the inverter's efficiency.
- Solar Charge Controller Size Calculator (PWM / MPPT)The controller your array needs: minimum current from the panels' short-circuit rating with the 125% factor, the cold-weather open-circuit voltage your controller must survive, and what MPPT gains over PWM.
- Solar Panel Size CalculatorHow many kilowatts of panels your house needs: from your daily units, the peak sun hours where you live and honest system losses — with the panel count and the roof area they take.