Both Octopus Go and Octopus Intelligent offer cheap overnight electricity — roughly 7p per kWh during off-peak hours, compared to around 25p at other times. But they work quite differently, and if you have solar panels or a battery, those differences are worth understanding before you switch.
How each tariff works
Octopus Go has a fixed off-peak window — currently 00:30 to 04:30 every night — at around 7p per kWh. Outside that window, you pay the standard rate. Beyond a smart meter, there are no special requirements: it works with any charger or battery system, and you schedule things yourself. Set your charger and battery to charge during those hours and that’s largely it.
Octopus Intelligent is built around EV charging. It connects to a compatible charger (Zappi, Wallbox, Ohme, Hypervolt, and others) through an app, and Octopus automatically schedules your car to charge at the cheapest available times within a wider overnight window. Rather than a fixed four-hour slot, Intelligent dispatches charging across more flexible periods — which often means more hours at the cheap rate than Go provides. The trade-off is that it requires a compatible charger linked to your account.
Solar and battery, but no EV
If you have solar and a battery but no electric car, Intelligent isn’t really designed for you — its scheduling logic is built around vehicle charging. Go is the more natural fit. Schedule the battery to charge during the cheap window, run it down through the morning before the panels pick up, and let solar top it back up through the day.
Octopus Agile is worth a mention here too. It prices electricity in half-hourly slots based on wholesale rates, and on cheap or negative-price periods — which happen fairly regularly — you can charge the battery for almost nothing. The trade-off is complexity: you need the battery to respond to price signals, either through its own scheduler or via Home Assistant or a similar integration. For people happy to set that up, it can squeeze more value out of the system than Go.
Solar, a battery, and an EV
This is where Intelligent starts to pull ahead on the EV side. It handles car scheduling automatically — you tell it when the car needs to be ready, and it finds the cheapest slots to get there overnight. During the day, your solar can divert into the car via the charger’s eco mode alongside the Intelligent scheduling.
The complication is the battery. Octopus Intelligent manages the car, not the battery, so battery charging still needs to be scheduled separately through the battery’s own app. You also need to make sure the system is wired so the battery doesn’t try to discharge into the car during the overnight cheap window — something that comes down to CT clamp placement and Henley block configuration, which we’ve covered in our guide to wiring EV chargers and battery systems.
On Go, you have more direct control — you schedule both the car and battery yourself. More setup upfront, but fewer interactions between systems you haven’t explicitly configured.
The export side
Both tariffs are compatible with the Smart Export Guarantee. You can export surplus solar on either and get paid for it through a separate SEG arrangement. Neither tariff affects your export payments.
Which to go for
For most solar households with an EV and a compatible charger, Intelligent makes sense — the automatic scheduling is genuinely useful and the extended cheap window adds up over the year. For households with a battery but no EV, Go is simpler and works well. If you want to optimise aggressively and don’t mind a more involved setup, Agile gives you the most flexibility.
If you’re planning a solar, battery, or EV charger installation in Bristol or South Gloucestershire and want to make sure the wiring suits whichever tariff you’re on, get in touch.
