System voltage: volts

Appliance Power (watts) Hours per day Wh per day
Total Watt-hours per day:

(equivalent to   Amp-hours for a   volt system)

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Solar panel calculator

To calculate approximately how much electricity you use every day in watt-hours (Wh), enter the power of each appliance in watts and the average length of time it is on for each day, in hours.

For guidance you can click on the 'show me an example' text below the calculator, which will enter some sample data into the grid. You can then revise these figures with an estimate of your own power consumption, remove those not relevant to your situation and add any additional items. Clicking the button will add the total Watt-hours for the individual appliances together, to give you a daily total.

Power ratings can often be found on information plates on appliances, or instruction booklets. Note however that these are normally the maximum power draw - a radio may be rated at 50W for example, but only when it is blasting out at full volume. Fridges draw a lot of power, but usually the pump switches on every few minutes rather than running continually. You may have to make a guess at the amount of time it is actually drawing power for each day.



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