If you drive an electric car, Intelligent Octopus Go is the tariff to beat. If you have solar panels plus a home battery, Octopus Flux turns your roof into a small business. If you heat with a heat pump, Cosy Octopus gives you eight cheap hours of electricity a day. In the Octopus Intelligent Go vs Flux debate, Go rewards shifting consumption into the night; Flux rewards selling stored power at tea time. Which fits depends on what your home already has.

Figures below reflect published trackers as of 3 October 2026. Rates vary by region, so confirm before switching.

What a time-of-use tariff actually is

Most of us are on a flat tariff: every unit costs roughly the same, whatever the hour. Time-of-use flips that. Electricity is cheap when the grid is quiet (deep night) and expensive when everyone wants it at once (the 4-7pm peak). A smart meter prices each half-hour chunk honestly, so shifting heavy usage into the cheap slots costs a fraction of the flat rate. Both halves of the Octopus Intelligent Go vs Flux question work this way: one discounts what you use, the other values what you export.

Intelligent Octopus Go: the EV tariff

Six hours of cheap power every night, 23:30 to 05:30, currently around 8p/kWh off-peak against a day rate of roughly 26-34p depending on region. The clever part: when Octopus smart-charges your car outside the window because the grid is quiet, your whole house gets the cheap rate during that session, so overnight appliances stack extra savings.

The catch: Octopus controls your car or charger, so yours must be on their compatibility list. Typical savings: £500-£600 a year on charging alone, which is why EV owners usually find the Octopus Intelligent Go vs Flux debate ends quickly in Go’s favour. Check Octopus’s Intelligent Octopus Go page for the latest rates and the list of compatible cars and chargers.

Octopus Flux: the solar + battery tariff

Flux prices your exports by time of day. Published September 2026 rates put peak exports (4-7pm) at roughly 29p/kWh, daytime at about 10p and overnight near 5p. Import is also banded: around 15p in the small hours (02:00-05:00) versus about 35p at peak. The strategy writes itself: solar fills your battery by day; at tea time you either run the house from it (dodging a ~35p import) or sell surplus back at 29p, then top up overnight at 15p.

Flux needs solar, a battery, a smart meter and Octopus as your supplier, and has recently reopened to new sign-ups after a spring 2026 pause. If you have the panels and the battery, the Octopus Intelligent Go vs Flux answer points the other way: Flux pays you for what the roof produces.

Cosy Octopus: the heat pump tariff

Cosy gives you eight cheaper hours every day across three windows: 04:00-07:00, 13:00-16:00 and 22:00-midnight, at about half the standard day rate (trackers put it around 14p). The trade-off is a peak rate from 16:00-19:00, roughly 45% above the day rate. You need a heat pump (or electric boiler) and a half-hourly smart meter; see Octopus’s Cosy Octopus page for the latest rates.

Octopus Intelligent Go vs Flux vs Cosy: which fits your home?

• EV, no solar: Intelligent Go. Night charging at 8p is the simplest big win here.
• Solar + battery: Flux. Nobody else pays you 29p for a 5pm export.
• Heat pump: Cosy. Eight discounted hours a day matches how a heat pump wants to run.
• None of the above: stay on the standard tariff while you plan the retrofit. Insulation first.

The retrofit ladder to a near-zero bill

1. Insulate first. Loft top-ups and draught-proofing are the cheapest kWh you will ever buy: the one you never use. (See cutting home energy bills this winter.)
2. Solar panels. A typical 4kWp array generates around 3,400 kWh a year. Self-consumed, that displaces imports at 26p; exported on Flux at peak, it earns 29p. If yours underperform, find out why before buying more hardware.
3. Home battery (5-10kWh). This unlocks Flux properly: it shifts your solar into the 4-7pm peak instead of dribbling back at daytime rates.
4. Heat pump. With seasonal efficiency around 3-4, Cosy halves the electricity price for eight hours a day, plus extras like Google’s payments for heat-pump homes.

A well-insulated home with 4kWp of solar, a 10kWh battery and a heat pump on the right tariff can realistically halve its electricity bill, and in a good solar year push toward zero. Whether the Octopus Intelligent Go vs Flux vs Cosy comparison lands you on Go, Flux or Cosy, the ladder below is the same. The capital cost is real (often £15k-£25k before the £7,500 Boiler Upgrade Scheme grant): each step makes the next one pay faster.

Frequently asked questions

Can I be on two Octopus tariffs at once?

No, you pick one import tariff. But Flux bundles import and export, and Cosy works with Octopus’s Outgoing export tariffs.

Is a £0 energy bill genuinely possible?

Plausible for a well-insulated, solar-equipped, battery-backed home on Flux, at least in some years. Treat £0 as the stretch target and a 50-70% cut as the realistic prize.

Do I need a smart meter?

Yes for all three. Cosy needs half-hourly readings (usually a SMETS2 meter); Octopus installs one free if yours is incompatible.

What if I rent?

Intelligent Go is still open if you have an EV, since it needs no home modifications. Otherwise, plug-in solar (legal in the UK since August 2026) can shave around £150 a year off your bill, no roof required.

Tariff check date: 3 October 2026. Figures come from Octopus’s published terms and third-party trackers (Energy Stats, Home Energy Quotes, Ecoaim, jmegreenenergy). Rates vary by region and can change: verify your exact prices before switching.