Octopus Nook vs Habo Energy: Price Comparison 2026

Why this comparison comes with an asterisk

If you have landed here after reading about the Octopus Nook launch, the first thing to be clear about is that Octopus did not announce a price. At the Octopus Energy Tech Summit on 22 June 2026, CEO Greg Jackson held up the Nook Cube and said two things about money: the Nook Colossus will be "about a third cheaper than the best-known battery brands", and the 2kWh Cube will "pay for itself in two or three years". That is it. No Cube price, no Colossus price, no per-kWh figure, and no on-sale date beyond "next year".

So any head-to-head price table involving the Nook is, by definition, an estimate against a known number. The known number is the Habo Energy price: £4,599 fully installed for an 11.5kWh battery, with MCS-certified installation, 0% VAT and a 10-year warranty, available to reserve today. Everything in the Nook column below is our best reconstruction from Jackson's claims and current market pricing, and we have flagged it as such.

The headline price comparison

Here is the cleanest side-by-side we can build. The Nook figures are estimates derived from the launch claims; the Habo figures are published prices.

The single most useful row is price per usable kWh of installed storage, because that is the only fair way to compare a 2kWh box, a 10kWh wall unit and an 11.5kWh system. On that measure the estimated Colossus (£450 to £550 per kWh) is more expensive than the Habo battery (about £400 per kWh), even before you factor in that the Habo price is real and the Colossus price is a guess.

Where the Nook Cube number comes from

The Cube is the easier of the two to anchor because Jackson tied it to payback, not to a competitor. A 2kWh plug-in battery on Octopus Go realistically saves around £170 to £200 a year (full daily cycle, 9.5p overnight versus roughly 32p peak, minus round-trip losses). For "two or three years" payback to be honest, the Cube has to retail at roughly £400 to £600. Add a little headroom and £400 to £700 is the sensible estimate range.

At face value that is far cheaper than £4,599. But the Cube only stores 2kWh and only saves around a fifth of what an 11.5kWh battery saves. Per kWh of storage it is competitive, not revolutionary, and to reach Habo-equivalent capacity you would need five or six Cubes, five or six spare double sockets, and you would still have no whole-home backup. The Cube is the right product for renters and flats with no install path, not a cheaper route to a full home battery.

Where the Nook Colossus number comes from

The Colossus is benchmarked by Jackson against "the best-known battery brands". In UK search results that means Tesla Powerwall 3, which sells from around £7,499 fully installed for 13.5kWh, or about £555 per usable kWh. A third off that headline puts the Colossus near £370 to £400 per usable kWh, which for a 10kWh unit lands somewhere around £4,500 to £5,500 fully installed once you account for the cabling, inverter and labour that the Tesla figure also includes.

In other words, the most aggressive thing Octopus has said about Colossus pricing still only gets it to parity with what you can already buy from a UK installer today. If the Colossus launches at the top of its estimated range, it is more expensive than the Habo battery for less usable storage.

The bit the price tag hides: when you start saving

A price comparison that stops at the sticker misses the biggest number, which is the saving you forgo while you wait. The Habo battery is installed and earning from the month you buy it. The Nook does not go on sale until 2027, and the Colossus realistically lands in the second half of that year once BS 7671 and PAS 63100 conformity is done.

For the Colossus to win on lifetime cost, it has to launch before 31 March 2027 so 0% VAT still applies, undercut the Habo price by more than £900, and avoid a long install queue. The first is plausible, the second is unlikely given the "third cheaper than Tesla" benchmark lands at parity with Habo, and the third is not within Octopus' control given the waiting list demand confirmed at ETS 2026.

So which is cheaper?

The bottom line

We cannot give you an exact Nook-versus-Habo price because Octopus has not published one and will not sell the Nook until 2027. What we can say with confidence is that the most optimistic reading of Octopus' own launch claims puts the Nook Colossus at roughly the same installed price per kWh as the Habo Energy battery, which is already on sale at £4,599 fully installed for 11.5kWh with 0% VAT and MCS certification. The Cube is cheaper but smaller and aimed at renters. For a homeowner who wants whole-home storage, there is no waiting-and-saving version of this where the 2027 Nook beats buying an installed battery today. If a real Nook price lands and changes that, we will update this page.