Octopus Energy's Own Plug-In Solar Kit: What the M1-800-E Means for You

Octopus Energy has quietly done something none of the big six-turned-big-whatever-it-is-now suppliers have bothered with: it's put its own name on an ENA-compliant plug-in solar kit. The device, listed in the ENA compliance registry as the M1-800-E, passed G98 testing in early September and is now legally fine to plug into any UK socket under the same SI 2026 No. 848 rules that cover every other 800W kit on the market. For a supplier that's spent the last few years building out Agile, Flux and the Intelligent Octopus family of tariffs, launching hardware is a logical next step — and it changes the calculation for anyone who's already an Octopus customer and has been eyeing up plug-in solar.

What is the M1-800-E, actually?

Strip away the branding and the M1-800-E is a conventional 800W, single-phase microinverter system — the same basic architecture as the vast majority of kits on the ENA list, including the entry from Solarfy. It sits within the standard 800VA/3.5A output cap that defines the whole plug-in microgenerator category, uses a BS 1363 plug fitted with the mandatory 5A fuse, and has no battery built into the plug circuit — so like every compliant kit, what it generates during the day either gets used immediately or is exported, with no way to store it for the evening peak unless you add a separate power station.

What's different is the ecosystem it's designed to sit inside. Octopus has built the M1-800-E's companion app to talk directly to the same account infrastructure that already runs your smart meter data, your tariff, and (if you're on it) Intelligent Octopus Go charging schedules. In practice that means your generation shows up alongside your existing consumption data in the Octopus app rather than in a separate manufacturer app you have to check independently — a genuinely useful bit of integration that EcoFlow, Anker and the rest can't replicate unless you're also happy to sync accounts manually.

How it compares to EcoFlow STREAM and the rest

The EcoFlow STREAM remains the best-known name in the category since its September 2026 launch, and it still has one structural advantage the M1-800-E doesn't: a genuine battery-backed version (STREAM Ultra) that can shift generation into the evening, something no base-spec plug-in kit can do within the no-battery-in-plug-circuit rule. If you want storage, you're buying a separate power station regardless of which panel kit you start with — see our battery storage vs no battery guide for how that trade-off actually plays out financially.

Where the M1-800-E earns its place is price and account simplicity for existing Octopus customers. Early listings put it competitively against the cheapest plug-in solar kits already on the market, and because Octopus already holds your meter data, there's no separate app login, no manual tariff entry, and — if you're on Flux — your generation numbers appear right next to the half-hourly pricing data you're probably already checking obsessively.

Should you switch tariffs to get it?

No — and this is worth being clear about, because some early coverage has implied the kit is tariff-locked. It isn't. The M1-800-E is sold as standalone hardware; you don't need to be on any particular Octopus tariff to buy or run one, and it will work perfectly well if you're actually with British Gas or E.ON. That said, the app integration is noticeably smoother if you are an Octopus customer, and if you're already comparing Octopus against British Gas and E.ON for solar users, a free, well-integrated generation dashboard is a reasonable tie-breaker in Octopus's favour.

Installation and DNO notification

Nothing changes here versus any other compliant kit. You still need to submit a G98 DNO notification before switching it on, the panel still needs a reasonably unshaded south-facing (or east/west-split) spot, and you still can't run it through an extension lead — it has to go straight into a wall socket.

Does it actually save more money than a generic kit?

Not in raw generation terms — an 800W microinverter produces roughly the same output whoever badges it, assuming similar panel efficiency and siting. The saving, if there is one, is in time and friction: no separate app to manage, no manual entry of your tariff rates to estimate savings, and generation data that sits next to your existing bill breakdown. For someone who wants to buy a kit, plug it in, and not think about it again, that's a real (if modest) advantage. For someone who's happy to use a third-party monitoring app anyway, it's largely cosmetic.

Is the Octopus M1-800-E cheaper than EcoFlow STREAM?

Pricing moves around with promotions on both sides, so check current listings before assuming either is cheaper — but the two have typically launched within a similar band for equivalent 800W specs. The bigger differentiator is ecosystem integration rather than raw price.

Do I need to be an Octopus Energy customer to buy or use the M1-800-E?

No. It's sold as standalone compliant hardware and works on any electricity account. You just get smoother app integration if you happen to already be with Octopus.

Does the M1-800-E include a battery?

No — like every other compliant plug-in kit sold under the current rules, it has no battery in the plug circuit. If you want to store generation for evening use, you'll need a separate portable power station alongside it.