The calculator is intended to provide a useful insight into your electrical energy use in your vehicle. It will help you to work out what capacity battery you will need when you're off-grid. We have used the most commonly used appliances in the calculator but there are additional fields for both 12V and 240V appliances if we've missed out your must-have piece of kit.

The Typical Watt rating fields show what an average appliance of that type will use. If you know the exact Watt rating of your appliance, you can enter that into the field. Otherwise, just leave the average figure as it is.

The Minutes usage per day fields can be filled in with your estimate of the time you will use each appliance on a daily basis.

You can clear all the fields by clicking the Clear Inputs button at the bottom of the calculator. Refresh the page to restore the "typical" values.