Battery Backup Reserve Calculator
Estimate the battery energy capacity to reserve for essential home loads during a planned outage, using their combined demand, backup duration, and a usable-capacity allowance.
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Calculators
Calculators
Planning tools for solar basics & home energy, with visible assumptions and units.
Battery Usable Capacity Calculator
Estimate the usable energy in a battery bank from each battery’s rated capacity, the number of batteries, and the allowed depth of discharge. The estimate assumes identical batteries and does not account for conversion losses or manufacturer-specific limits.
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Electricity Bill Comparison Calculator
Compare two modeled electricity bills from monthly usage, energy rates, and fixed charges. The result is the signed dollar difference between Bill A and Bill B.
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Household Daily Electricity Use Calculator
Estimate your household's daily electricity use in kilowatt-hours from appliance power, daily operating time, and quantity. The estimate assumes each appliance runs at a steady rated wattage for the hours entered.
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Inverter Energy Loss Calculator
Estimate the energy an inverter loses by comparing its DC energy input with its AC energy output over a chosen period. This arithmetic estimate assumes both readings cover the same system and time interval.
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Peak Sun Hours Estimate Calculator
Estimate equivalent peak sun hours from daily solar irradiation. Enter irradiation in kilowatt-hours per square meter per day; the result uses the standard equivalent-hour interpretation and is not a site-specific production forecast.
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Portable Solar Power Budget Calculator
Estimate a planning budget for a portable solar setup from the power station, panel, and accessory costs you enter, plus a chosen contingency allowance. This is a simple cost worksheet and does not determine system suitability or predict energy production.
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Solar Annual Production Estimate Calculator
Estimate a solar panel system's annual electricity production from its rated capacity, peak sun hours, performance ratio, and days in a year. This simplified estimate assumes consistent average conditions and does not model hourly weather or shading changes.
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Solar Battery Runtime Calculator
Estimate how many hours a battery can supply a steady electrical load using its usable energy and the load's average power. This simplified estimate does not account for inverter losses, changing loads, or other system limits.
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Solar Capacity Factor Calculator
Calculate the capacity factor over a reader-defined reporting interval from generated electrical energy, stated electrical nameplate capacity and elapsed hours. Use a consistent reporting basis and the same interval; this does not infer dates or forecast output.
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Solar Energy Unit Conversion Calculator
Convert an amount of solar energy between watt-hours, kilowatt-hours, megawatt-hours, and joules using a selected source and target unit.
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Solar Export Income Estimate Calculator
Estimate gross income from solar electricity exported to the grid over a chosen period. Enter exported energy, your export rate, and the period length. This simple estimate assumes a constant rate and excludes fees, taxes, and other contract terms.
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Solar Installation Cost Per Watt Calculator
Estimate a residential solar installation's total project cost per watt from the installed project cost and system size. This simple ratio does not account for incentives, financing, or equipment differences.
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Solar Panel Daily Output Estimate Calculator
Estimate a solar array's average daily energy production from its rated capacity, peak sun hours, and an assumed system efficiency. This planning estimate does not predict a specific day's weather or guarantee actual output.
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Solar Panel Efficiency Calculator
Estimate a solar panel’s conversion efficiency from its rated power output and active surface area. The result is a percentage based on the supplied inputs and does not predict a system’s energy production.
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Solar Panel System Energy Cost Calculator
Estimate the electricity cost of energy produced by a solar panel system over a chosen period. Enter the energy produced and the electricity rate you want to use. This arithmetic estimate assumes the entered energy and rate apply to the same period and excludes fixed charges, taxes, and other fees.
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Solar Roof Area Estimate Calculator
Estimate the roof area occupied by a solar array from panel count and panel dimensions, with an optional allowance for layout spacing. This is a planning estimate, not a roof suitability or structural assessment.
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Solar Self-Consumption Percentage Calculator
Estimate the share of your solar electricity generation used by your home during the same period. Enter solar generation and the portion exported to the grid, using matching energy units and time periods.
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Solar Simple Payback Calculator
Estimate simple payback in years by dividing a home's upfront solar system cost by its estimated annual bill savings. This basic calculation does not account for financing, incentives, maintenance, utility rate changes, or the time value of money.
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Solar System Size Estimate Calculator
Estimate the solar array capacity needed to meet a share of your household's daily electricity use, using peak sun hours and an assumed system efficiency. This planning estimate does not size batteries or replace a site assessment.
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