Your devices are working correctly. They just cannot see each other.
When Octopus charges your EV during the day, your battery discharges to supply the load — because it has no way to know cheap grid power is available. 1app.energy reads every device simultaneously and makes the decision your inverter cannot: hold the battery, let the grid do the work, and optionally charge the battery further while the cheap window is open.
The problem
Each device is optimising for itself — not for your home
A battery can only do one thing at a time: charge or discharge. Understanding this is the key to understanding where money is quietly being lost.
Phase 1 — Working correctly
Off-peak window (e.g. 00:30–05:30)
Your battery is charging. Because it cannot charge and discharge simultaneously, your home — lights, heat pump, all overnight loads — runs entirely from cheap grid electricity. Your EV also charges. Everything that draws power during this window pays the off-peak rate. This is working exactly as intended.
Phase 2 — Where the conflict happens
After the window closes
Your battery switches to discharge mode. Octopus Intelligent Go then dispatches a daytime EV session — at 13:00, 15:30, whenever the grid is clean. Your charger draws 7kW. Your inverter sees the load and does what it is configured to do: the battery discharges to supply it. Solar storage built up that morning is consumed by the car instead of being available for the evening peak.
A real winter day — what actually happens
Off-peak window opens
Battery starts charging. Car also starts charging. Home loads run from cheap grid. Battery reaches 85% by 05:00.
Off-peak window closes
Battery switches to discharge mode. Heat pump starts its morning pre-heat cycle. Battery supplies the load — this is correct.
Solar generating
4kW array producing. Battery charges further from solar. Reaches 90% by midday on a good spring day.
Octopus dispatches a daytime EV session
Your charger starts drawing 7kW. Your inverter sees the load and the battery — in discharge mode — begins supplying it. Over 90 minutes, 7–8kWh of solar storage is consumed by the car.
Peak-rate evening begins
Battery is at 25% instead of 80%. Grid imports at 30p/kWh fill the gap that solar storage should have covered. The battery did its job — just for the wrong load.
How 1app sees your home
Four live data connections. One coordination layer.
Every device in your home has its own app. None of them talk to each other. 1app.energy reads all four simultaneously — and acts on what it sees.
Octopus Energy
- —Live dispatch signals — when a smart session starts
- —Upcoming cheap windows (Agile half-hourly, Go schedule)
- —Current tariff rate (import and export)
Solis Inverter
- —Battery state of charge — right now
- —Solar generation rate
- —Grid import / export flow
Daikin Heat Pump
- —Current operating mode (heating, DHW, standby)
- —Power draw
- —Scheduled cycles
Zappi EV Charger
- —Session active or idle
- —Current draw rate
- —Charging mode (smart / boost / eco)
What 1app does
Two modes. One decision made automatically.
When a smart charging session is detected, 1app.energy acts immediately — before the battery has a chance to drain. The mode chosen depends on battery state, expected demand, and whether the cheap window makes additional charging worthwhile.
Mode 1
Hold
The battery is held in its current state. Everything — home loads and EV — runs from the Octopus grid supply during the session. The cheap rate benefit is fully realised: grid imports happen at the dispatched cheap rate, the battery is not consumed, and your solar storage is preserved for the evening peak.
Result
- ✓EV charges cheaply from grid
- ✓Battery stays full for the evening
- ✓Solar storage untouched
- ✓No manual schedule to maintain
Mode 2
Hold + Charge
The battery holds AND charges further during the session — using the same cheap grid supply that is charging your car. Your EV, your home, and your battery all draw at the cheap dispatched rate simultaneously. You end the session with more stored energy than you started with.
What this means for you
- ✓Extra stored energy for the evening peak
- ✓More to export on Flux or SEG tariffs
- ✓Avoids oversizing battery capacity
- ✓Fully automatic — no manual config
Supported devices
Which homes can 1app.energy coordinate today?
Inverters & batteries
- —Solis
EV chargers
- —Zappi (myenergi cloud)
Heat pumps
- —Daikin
Tariffs
- —Octopus Go
- —Octopus Intelligent Go
- —Octopus Agile
- —Octopus Flux
Not sure if your setup is supported? Check the full integrations list or tell us what you have installed and we will review it.
Ready to stop the drain?
Your setup might already qualify.
Tell us which devices and tariff you are on. We review every request and invite in order of fit — not sign-up date.