Solar Power

Calculate your Power Budget Requirements

The single most important thing you need to do if you are planning to boondock with solar is to build an honest power budget.
The power budget will allow you to design a system that will actually meet your needs and not lead to disappointment.

People online in different forums may tell you what they found works for them or you may hear this or that is the only way to go... This is all nonsense, if you want a system that will meet YOUR needs, start with YOUR power budget.

We created the downloadable Excel spreadsheet to assist in your build and hope you will find it useful.

In the spreadsheet, text that is shaded GREEN may be edited for your particular requirements.
Text that is shaded RED may not be edited as they are calculated fields. Once you have your numbers entered, save the results for your records.

The spreadsheet will also calculate Amps and Volts for Series and Parallel connections of you solar panels, as well as a Series-Parallel system.

There are 5 worksheets in the spreadsheet:
1. Start Page: Introduction
2. Solar Power Budget: List ALL of your electrical devices
3. Series-Parallel Calcs: Solar panel capacity calculations
4. AWG Calc: Calculate required wire gauge for an inverter
5. Ampacities: Conductor ampacity chart

We added some typical equipment for you already, you may add or edit these descriptions as needed for your system.
You may enter Amps or Watts depending on the information provided on the UL Listing Label on your device, the calculator will automatically calculate the Watt Hours.

The bottom 5 rows that are shaded are for devices that have a Duty Cycle, meaning that they run intermittently such as the examples given in those rows.
When possible for best results run the device for an hour and note how long it actually runs in total minutes during that hour and enter that information in the *Runtime Minutes" column, this will calculate the Duty Cycle percentage. If you cannot run the equipment yet, just enter 30 in the *Runtime Minutes" column for now.

The Ah/Day is the amount of Battery Capacity needed to run your devices for (1) 24 hour period.
The Net Power/Day at the bottom of the sheet is your calculated total wattage and amp hours of your solar panels minus your calculated usage.

Ideally the Net Power/Day - Watt/Hrs and Amp/Hrs should be positive numbers, if not consider adding more panels and/or battery capacity.

Updated 20-AUG-26
Should you find any errors, have questions about how to build your power budget, or have suggestions to help improve our budget calculator,
please feel free to contact us.