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Daily Power Consumption Calculator

List the devices you use and choose the type of value you have for each device: running watts, volts and amps, or energy in kWh/day or kWh/year. Choose how each device is powered to see separate DC and inverter AC totals for battery or solar planning.

Not sure what to enter? Read the step-by-step guide.

Your inputs

Add the devices you use on a typical day. Results update as you enter your numbers.

Device 1

Enter the values for one device. The calculator multiplies its energy use by Quantity.

This only affects how Wh/day is grouped for battery and solar planning; it does not change the device’s calculated energy use.

Check your device label, manual, energy label, or a power meter. For watts and amps, enter actual running hours; for kWh inputs, the energy already includes time. Choose how the device is powered separately from the value shown on its label. Inputs stay in this browser.

Daily estimate

Your daily energy

Energy used by your devices, before inverter losses.

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By power source

Direct DC from battery—

AC through battery inverter—

Other source—

Not specified—

Plan your next step

Battery Size, Solar Size and System Checker use the DC and inverter AC totals above. They account for inverter losses separately for AC loads; other power sources are excluded.

Add battery-powered devices and choose their power sources to use these totals in another calculator.

    Enter a device to see its daily energy use.

    All totals show energy used by the listed devices. DC/AC groups are based on your chosen power source and do not include inverter losses or battery capacity adjustments. Devices marked “Other source” or “Not specified yet” are excluded from battery and solar inputs.

    Edit your inputs
    See calculation details, assumptions and sources

    For each device: Wh/day = quantity × running watts × hours actually running per day. For DC, watts = volts × amps. For single-phase AC, real watts = RMS volts × RMS amps × power factor; power factor must come from your device information or measurement.

    If you have kWh/day, multiply by 1,000 to get Wh/day. If you have kWh/year, divide by 365 first for an average day. Multiply by quantity, then add all devices. Divide total Wh/day by 1,000 to show kWh/day. Do not add running hours to an energy-label value.

    Each device's Wh/day is also grouped by the power path you select: direct DC from battery, AC through a battery inverter, another source, or not specified. The input type determines how energy is calculated, but not how the device is powered in your RV.

    For example, two 60 W laptops used for five hours each consume an estimated 2 × 60 × 5 = 600 Wh/day. A fridge's compressor may cycle; for watts or amps, enter the hours it actually runs rather than automatically using 24 hours. An annual kWh label is an average under its test conditions, so daily use may differ.

    These estimates cover the energy used by the devices themselves. AC loads supplied through an inverter need additional energy from a battery because of inverter losses; this calculator does not estimate that loss. Nameplate ratings may differ from measured use. These inputs do not account for startup surge.

    Method: U.S. Department of Energy guidance on calculating daily load. See the site methodology for the wider approach.