AC Power Factor Calculator
Calculate AC power factor from real power and apparent power. Enter watts and volt-amperes to get a dimensionless ratio from 0 to 1.
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Calculators
Calculators
Planning tools for energy technology & portable power, with visible assumptions and units.
Appliance Energy Consumption Calculator
Estimate an appliance’s electricity use in kilowatt-hours from its rated power, daily operating time, and days used. The estimate assumes the appliance draws its rated power whenever it runs.
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Backup Power Energy Budget Calculator
Estimate the usable energy budget for a backup power setup by comparing battery capacity with a chosen reserve and conversion efficiency. This is a planning estimate, not a runtime guarantee.
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Battery Cycle Cost Calculator
Estimate the cost of one battery charge-discharge cycle from purchase price, rated cycle life, usable capacity, and the share of capacity used per cycle. This simple model allocates purchase cost across rated cycles and adjusts for depth of discharge.
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Battery Depth of Discharge Calculator
Calculate the percentage of a battery's rated capacity used, based on its starting and remaining charge in amp-hours. This arithmetic estimate assumes both readings use the same capacity units and does not account for battery chemistry, temperature, aging, or measurement error.
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Battery Runtime Estimator
Estimate how long a battery can power an electrical load from its capacity, voltage, load power, and an assumed usable-energy fraction.
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DC Load Runtime Calculator
Estimate how long a DC load can run from a battery using its rated capacity, nominal voltage, load current, and an adjustable usable-capacity fraction. This simplified estimate assumes steady current and does not model battery-specific discharge curves or other system losses.
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Energy Storage Round-Trip Efficiency Calculator
Calculate the percentage of energy delivered by a storage system relative to the energy supplied to charge it, using measured energy input and output in kilowatt-hours.
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Energy Unit Conversion Calculator
Convert an energy quantity between joules, kilojoules, watt-hours, kilowatt-hours, calories, and British thermal units using standard unit conversion factors.
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Fuel Cell Electrical Efficiency Calculator
Estimate electrical efficiency from hydrogen fuel energy input and net electrical output. Choose the hydrogen heating-value basis used for the fuel energy input; the input energy must use that same basis. This calculator does not convert between heating-value bases.
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Generator Fuel Cost Calculator
Estimate generator fuel cost from runtime, fuel consumption, and fuel price. This simple estimate assumes fuel use and price stay constant during the selected run.
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Hydrogen Energy Unit Conversion Calculator
Convert a quantity of energy between joules, kilojoules, megajoules, watt-hours, and kilowatt-hours using standard unit relationships. Enter the energy value and select its current unit and the unit you want.
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Inverter Efficiency Calculator
Estimate an inverter's conversion efficiency by comparing its AC output power with its DC input power. Enter power in watts under the same operating conditions. This simple ratio does not account for measurement uncertainty or performance across a full load range.
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Power Equipment Operating Cost Calculator
Estimate the hourly operating cost of power equipment from fuel or electricity use, energy price, maintenance, and annual fixed costs spread across yearly operating hours.
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Power Outage Reserve Capacity Calculator
Estimate the battery energy capacity needed to run selected essential loads for a planned outage duration, with an allowance for inverter losses and a reserve margin. This is a planning estimate based on average load, not a runtime or equipment performance guarantee.
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Power Station Cost per Watt-Hour Calculator
Estimate a portable power station's purchase cost per watt-hour from its price and rated energy capacity. The calculation uses the listed price and capacity only, so it does not include accessories, usable-capacity differences, or lifetime energy delivered.
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Solar Charging Time Estimate Calculator
Estimate ideal solar charging time from the battery energy still needed and the solar panel system's usable power. Assumes constant usable output and does not account for changing sunlight or equipment losses beyond the efficiency you enter.
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Solar Panel Daily Energy Estimate Calculator
Estimate a solar array’s daily energy production from its rated capacity, peak sun hours, and an assumed system efficiency. The result is a planning estimate in kilowatt-hours per day, not a performance guarantee.
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Watt Hours to Kilowatt Hours Calculator
Convert an energy amount from watt hours (Wh) to kilowatt hours (kWh) by dividing watt hours by 1,000.
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Watts to Amps Calculator
Convert electrical power in watts to current in amps using voltage and, for AC circuits, power factor. This estimate assumes a single-phase circuit and does not account for wiring, equipment ratings, or electrical code requirements.
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