Home Energy Desk tools
Battery Calculators
Estimate battery runtime, charging time, current, usable energy, capacity conversions, expansion, degradation, and payback.
Explore every battery calculators
Battery Backup Runtime Calculator
Estimate usable battery energy and backup time from capacity, state of charge, reserve level, load, and inverter efficiency.
Battery Charging Time Calculator
Estimate input energy and charging duration for a home battery between two state-of-charge levels.
kWh to Ah Calculator
Convert battery energy in kilowatt-hours to amp-hours at a selected nominal voltage and conversion efficiency.
Ah to kWh Calculator
Convert amp-hour capacity to nominal and usable kilowatt-hours using battery voltage, usable capacity, and system efficiency.
Battery Bank Series and Parallel Calculator
Calculate total voltage, amp-hour capacity, energy, and unit count for batteries connected in series and parallel.
Battery Current Calculator
Estimate DC battery current required to supply a given AC or DC power load at a selected battery voltage and conversion efficiency.
Usable Battery Capacity Calculator
Estimate the energy available between current state of charge and a selected minimum reserve, after efficiency losses.
Battery Depth of Discharge Calculator
Calculate depth of discharge, remaining state of charge, and energy used during a battery cycle.
Battery Expansion Calculator
Estimate combined capacity and backup runtime after adding compatible battery modules to an existing system.
Battery Degradation Calculator
Estimate retained capacity, total degradation, and average annual capacity loss from original and currently measured capacity.
Home Battery Payback Calculator
Estimate simple payback and multi-year net benefit for a home battery using installed cost, incentives, bill savings, and annual costs.
Battery C-Rate Calculator
Calculate battery charge or discharge C-rate from current, power, voltage, and rated capacity.
Battery Recharge from Solar Calculator
Estimate how much solar array power and sunlight time are needed to recharge a battery from its current state of charge.
Battery Lifetime Cost per kWh Calculator
Estimate the levelized cost of energy delivered by a home battery over its warranted or expected service life.
Battery Cycle Life and Years Calculator
Estimate equivalent full cycles per year and the earlier of cycle-limited or calendar-limited battery service life.
Battery Reserve State-of-Charge Runtime Calculator
Calculate how much outage runtime remains at a chosen battery reserve state of charge and how changing the reserve affects available backup.
Home Battery Time-of-Use Savings Calculator
Estimate annual savings from charging a home battery during off-peak periods and discharging it during peak-rate periods.
How to use these tools
Choose the calculator that matches your decision, enter values from equipment labels, utility bills, manuals, or verified specifications, and test more than one scenario. Calculator results are planning estimates. Confirm electrical, structural, HVAC, battery, and code-sensitive decisions with qualified professionals and applicable local requirements.