GreenWattWise LabCalculation tool
Home Battery Decision Calculator
Explore your own household and battery scenarios and test how different assumptions affect the decision. This is an educational decision-support tool, not a final electrical or engineering design.
What it helps with
- Work through your own household numbers instead of a generic example
- Compare how different battery capacities (5, 7.5, 10, 13.5+ kWh) fit your situation
- Test how assumptions about consumption, solar, and goals change the sizing result
- Sanity-check a battery size an installer has already quoted
Who it's for
- Homeowners actively comparing installer quotes
- Solar PV owners weighing more than one battery capacity
- Anyone who wants to test their own numbers, not just a worked example
What you receive
- The GreenWattWiseLab Home Battery Decision Calculator (Excel-based)
- A worked example file showing the calculator filled in end to end
Difference from the free calculator
The free Home Battery Size Calculator gives you a quick sizing estimate in your browser. The Home Battery Decision Calculator is designed for deeper scenario exploration when you're actively evaluating a battery purchase — working through your own numbers at your own pace, offline, in a spreadsheet you keep.
Want the complete buying system?
The Home Battery Buyer Toolkit bundles this calculator with the Essential Edition guide and the additional buyer resources included in the Toolkit.