Excess Solar Priority Calculator
Decide where excess solar should go first.
This calculator helps you rank the four most common uses for daytime solar surplus so you can stop treating every exported kWh as if it should automatically go to a battery.
Your result will appear here
Submit the form to get a recommendation profile, supporting reasons, suggested next steps, and relevant devices, integrations, or guides.
How to use this excess-solar tool properly
What this tool helps with
Use it when your home is already exporting solar and you want to know what should get that surplus first: EV charging, hot water, comfort loads, battery, or another daytime load.
What improves the result
The strongest answers come from being realistic about whether the EV is home, whether hot water is actually shiftable, and whether daytime comfort loads really exist in the house already.
How to read the result
Treat the top priority as the first thing to test or improve, not as proof that every lower-ranked option is bad. The real goal is usually cheapest useful self-consumption first, then more expensive upgrades later.
What changes the order fastest
EV daytime presence can reorder the list immediately
If the car is actually home during strong solar hours, EV charging can jump ahead quickly because it can absorb meaningful energy at retail-value replacement.
Hot water is often the simplest controllable load
When hot water timing is flexible, it can outrank a battery because it is a cheaper way to keep more solar on site.
Daytime occupancy can create a new middle ground
If people are regularly home and the house has flexible AC or a heat pump, daytime comfort loads can become a better first step than jumping straight to a battery.
Battery rises when the easy daytime loads are weak
If the EV is not around, hot water is not very flexible, and exports are recurring, battery storage moves up because the simpler loads are not enough.