AC-connected storage
A battery and inverter exchange energy through a defined AC connection. Connection and export controls still matter.
EMERGING MARKET TRACKER
Small batteries are changing home energy.
Track plug-in, balcony and portable crossover products — and understand the UK electrical and grid questions before buying.
How Battery Boost verifies dataUK + Europe
LIVE DATAPLAIN ENGLISHVERIFIED SOURCES
Balcony solar + storage
PV-first ecosystems are established in parts of Europe, but UK connection and installation requirements are product-specific.
Portable crossover
Portable power products are gaining home-energy functions without automatically becoming fixed home-battery systems.
PRODUCT / MARKET TRACKER
What is available, announced or market-dependent.
STREAM Ultra X
- Capacity
- 3.84 kWh; expandable to 23 kWh
- Power / connection
- 2.3 kW on-grid · 1.2 kW AC output · 2.3 kW max device load
- PV
- 2 kW PV input across four MPPTs
- Meter / control
- EcoFlow Smart Meter / Smart Plug
Solarbank 4 E5000 Pro
- Capacity
- 5.024 kWh base; expandable to 30 kWh
- Power / connection
- 2.5 kW on-grid output
- PV
- 5 kW PV input across four MPPTs
- Meter / control
- Anker Smart Meter Gen 2
SolarFlow ecosystem
- Capacity
- Modular
- Power / connection
- Market configuration dependent
- PV
- Balcony PV ecosystem
- Meter / control
- Smart meter options
NEXA / balcony storage ecosystem
- Capacity
- Model dependent
- Power / connection
- Market configuration dependent
- PV
- Integrated MPPT
- Meter / control
- Accessory dependent
VENUS E 4.0
- Capacity
- 5 kWh; up to 15 kWh with SmartBox
- Power / connection
- 3 kW bidirectional
- PV
- Not stated on cited product page
- Meter / control
- MARSTEK intelligence / VPP claim
Nook Cube
- Capacity
- 2 kWh; planned modular expansion
- Power / connection
- Plug-in concept
- PV
- Ecosystem dependent
- Meter / control
- Octopus platform
MiniQube S22
- Capacity
- 2 kWh class; modular
- Power / connection
- Product/market approval dependent
- PV
- Direct PV input
- Meter / control
- CT / smart meter concept
Plug-in does not mean regulation-free.
Connection method, protection, earthing, circuit capacity, export behaviour, product standards and manufacturer instructions all matter. Do not improvise a connection or use an extension lead. Seek competent electrical advice for the specific product and installation.
UNDERSTAND THE DETAILS
What to know before choosing.
What is a plug-in battery?
The phrase covers several products: portable power stations, AC-connected storage and balcony-solar batteries. They do not all connect, export or protect the circuit in the same way.
Why the market is growing
Smaller modular systems, smart meters and flexible tariffs make storage attractive to renters and homes without conventional rooftop solar. Regulation and product approval still differ by country.
Europe vs the UK
Balcony solar is established in parts of continental Europe. Britain has different wiring, connection and export arrangements, so an EU product page is not evidence of a suitable UK installation route.
What is available in Britain?
Some AC-connected and portable crossover systems are sold now; other plug-in concepts are announced or market-dependent. The tracker separates those states rather than treating them as equivalent.
LATEST SIGNALS
Recent changes from trusted sources.
E.ON publishes four current SEG tiers
E.ON lists 17.5p/kWh Next Export Premium v3 for qualifying E.ON-installed solar or battery systems, 13p/kWh Next Export Exclusive v3 for qualifying E.ON import customers, 6p/kWh variable Next Flex Export v1, and 8.5p/kWh Next Export Business v1 for qualifying SME or commercial generators. Installation date, import-tariff, system-size, metering and fixed-term conditions differ by tier; the headline rates are not generally available to every home.
Read source: E.ON NextScottishPower publishes three SmartGen export tiers
ScottishPower lists 6p/kWh SmartGen, 12p/kWh SmartGen Premium for qualifying import customers and 15p/kWh SmartGen Premium Plus for qualifying customers whose solar panels and/or battery were installed by ScottishPower. All three rates are variable; generation, certification, half-hour metering and DNO evidence requirements still apply.
Read source: ScottishPowerGovernment launches UK-wide lower-cost battery loans
The Warm Homes Loan Scheme supports no- and low-interest finance for household clean-energy upgrades across the UK, including electrical storage battery loans of up to £15,000. Ten lenders are participating initially and installations must use MCS-certified installers. This is repayable finance, not a battery grant: rates, installer restrictions, term, fees and the total amount repayable still need comparing.
Read source: Department for Energy Security and Net ZeroGovernment sets tariff-data interoperability rules for smart devices
The government has modified the Retail Energy Code to set how electricity suppliers must share tariff pricing data in a standardised format. The change takes effect on 6 November 2026, with Phase 1a planned to go live on 18 February 2027 so energy-smart appliances can respond more consistently to price signals. This is an interoperability framework, not a new retail tariff, a live battery-control service or a compatibility approval.
Read source: Department for Energy Security and Net ZeroSo Energy resolves So EV at 7.5p/kWh
So Energy's tariff index, dedicated So EV page and FAQ now agree on 7.5p/kWh from 00:00–05:00, resolving the previous 7.5p/6.5p supplier-page conflict. The overnight rate applies to the whole home; So Energy supply, a compatible half-hourly smart meter and the account-specific daytime price still matter.
Read source: So EnergyE.ON keeps £75 Next Drive Smart connection credit live
E.ON's current page identifies Next Drive Smart V7.9 at 6.5p/kWh, while its terms keep the limited £75 account credit for eligible existing customers who had not previously connected equipment and do so in the E.ON Next Home app from 14 October to 30 November 2026. They must remain connected for the eligibility check; E.ON says the credit should be applied by 14 December.
Read source: E.ON NextGovernment consults on consumer-authorised energy data sharing
The government proposes a legislative framework requiring specified energy datasets to be made securely available to authorised services when consumers choose to share them. The consultation covers datasets, accreditation, consumer protection, governance and funding; it does not yet create a live data-access route or authorise third-party battery control.
Read source: Department for Energy Security and Net ZeroOfgem closes low-carbon information consultation
Ofgem's consultation on objective, non-promotional information about battery storage, solar panels, EV chargers and heat pumps during smart-meter visits closed on 23 October and is awaiting a decision. Marketing without prior consent would remain prohibited under the proposal; this is not yet a final licence change.
Read source: OfgemGovernment considers V2G and V2H credits in ZEV mandate review
The Department for Transport's closed ZEV-mandate review asks whether manufacturers should receive a credit for cars and vans with meaningful UK V2G or V2H capability. Proposed criteria include UK-enabled bidirectional operation, G99 or ENA evidence, warranty support, a compatible UK charger, ISO 15118-20 and a live vehicle-charger-tariff proposition. This remains a policy proposal awaiting an outcome, not a new customer incentive or compatibility approval.
Read source: Department for TransportBritish Gas publishes four current SEG tiers
British Gas lists 12p/kWh Premium for electricity customers with systems up to 15kW, 8p Extra above 15kW, 6p VoidCare for qualifying social landlords up to 15kW and 3p Export SEG for non-supply customers, developers and larger VoidCare systems. It says eligible battery-storage export can qualify, but renewable-generation, certification, DNO and half-hourly metering rules still apply.
Read source: British GasE.ON Store & Save uses a single overnight window
E.ON Next's current terms set Store & Save's lower-priced period at 02:00–05:00. The 12-month fixed tariff requires a solar battery, half-hourly smart metering, Direct Debit and online account management, carries no exit fee and publishes no general unit rates, so the personalised quote remains decisive.
Read source: E.ON NextIntelligent Octopus Flux is again marked temporarily unavailable
Octopus's live page again says Intelligent Octopus Flux is temporarily unavailable. It also remains internally inconsistent over eligibility: one section says compatible equipment need not have been installed by Octopus, while another says the tariff is currently exclusive to Octopus solar-and-battery customers. Battery Boost therefore marks it paused and restricted pending a consistent reopening route.
Read source: Octopus EnergyE.ON opens Solar Storage Steady beta with fixed windows
E.ON Next's quote-only beta combines fixed import and export windows with automatic battery steering. It requires E.ON supply and SEG, a half-hourly smart meter and one of nine listed inverter ecosystems. E.ON does not publish general unit rates, so the personalised quote, exact model and export limits remain decisive.
Read source: E.ON NextNESO brings constraint actions into the Demand Flexibility Service
From 7 October, NESO says DFS can procure both margin and system-tagged constraint actions and the Local Constraint Market no longer procures constraint actions. Households still participate through registered providers; the change does not create a direct retail payment guarantee for an individual home battery.
Read source: NESOOfgem finds modest response to standing-charge flexibility rebates
Ofgem's two trials covered more than 43,000 British Gas and ScottishPower customers. A standing-charge rebate reduced 16:00–19:00 use modestly in only one trial, and doubling the maximum reward produced only a small extra reduction. The findings support cautious tariff design rather than a guaranteed saving or response for every household.
Read source: OfgemOctopus terms confirm landlord-linked Tenant Power
Octopus's smart-tariff terms describe a restricted proposition for homes with approved solar, a battery, import and export smart meters and a MID-approved whole-home submeter. The electricity discount is agreed with the landlord and moves with the price cap; no public unit rate or open sign-up route is stated, and Octopus controls the battery.
Read source: Octopus EnergyOfgem proposes a commitment fee for queued battery projects
Ofgem says around 90 GW of battery capacity is operational or in the reformed connections queue versus a projected 29 GW requirement by 2035. The consultation concerns larger grid-connected projects, not domestic battery registrations.
Read source: OfgemBudget extends domestic electricity VAT cut to July 2027
Budget 2026 extends the temporary 0% VAT rate on qualifying domestic electricity supplies for three more months, to 1 July 2027. The government expects the extension to reduce the April 2027 Ofgem price cap by around £50 a year. It changes the VAT component, not a supplier's underlying unit rate, standing charge or the economics of every battery tariff.
Read source: HM TreasuryOctopus publishes Charge Pack control and eligibility terms
The terms require a supported battery, compatible import and export tariff, working smart meter and battery control access. Sessions are at Octopus's discretion, and the terms restrict joining another demand-response scheme with the same asset.
Read source: Octopus EnergyOVO Charge Anytime PAYG remains at 13.33p/kWh
OVO's primary page dates its pay-as-you-go smart-charging rate at 13.33p/kWh from 1 October 2026. The figure is not the price of its separate fixed-monthly plans, and boost charging still uses the customer's standard home tariff.
Read source: OVO EnergyIntelligent Octopus Go moves to 6.5p/kWh
Octopus now advertises smart charging from 6.5p/kWh, including the six-hour 23:30–05:30 whole-home window and up to six hours of eligible managed charging. Day rates, standing charges and contract terms remain account-specific, and the live vehicle or charger compatibility check remains decisive.
Read source: Octopus EnergyBritish Gas confirms current EV Power and Hive Power+ figures
British Gas's current EV page shows EV Power at 9.5p/kWh from 00:00–05:00 and a 25% Hive Power+ discount, equivalent to 7.125p/kWh when combined. Its general energy page no longer displays the older 6.75p illustration, resolving the previous public-page inconsistency.
Read source: British GasAxle lists seven supported inverter ecosystems
Axle's beta proposition lists AlphaESS, Sigenergy, Fox ESS, GivEnergy, SolaX, Solis and SolarEdge. It advertises £1/kWh during qualifying grid-stress events and a £10 monthly minimum; actual operation still depends on a compatible battery and smart-meter connection.
Read source: Axle EnergyCharge Pack lists nine battery brands as eligible now
Octopus lists AlphaESS, EcoFlow, Enphase, FoxESS, GivEnergy, HanchuESS, Huawei, Sigenergy and SolarEdge as eligible, with Tesla, SolaX, LuxPower, Solis, GoodWe, Duracell and Hinen marked coming soon.
Read source: Octopus EnergyPower Pack still has one verified UK compatibility chain
Octopus currently names one live combination: a V2G-enabled BYD Dolphin with a V2G-enabled Zaptec Pro. Other vehicle and charger claims remain separate as trials, announcements or overseas products.
Read source: Octopus EnergyE.ON Next Optimise adds Sunsynk support
E.ON Next now lists six automatically compatible battery ecosystems, adding Sunsynk ECCO, Accure, Elite and 8–50kW three-phase inverters while excluding Lifelynk. Unsupported batteries may still join in self-optimise mode, where the customer manages scheduling; exact model and beta eligibility remain decisive.
Read source: E.ON NextNESO keeps generation and carbon datasets openly available
The system operator's data portal supports transparent tracking of how Great Britain's electricity is generated and how carbon intensity changes over time.
Read source: NESOElexon publishes near-real-time generation by fuel type
Operational metering data gives a current view of transmission-connected generation. Battery Boost labels embedded-solar estimates separately because they are not measured in the same feed.
Read source: ElexonHome Assistant adds Axle grid-event schedules and local inverter integrations
Home Assistant 2026.10 adds an Axle Energy integration that exposes upcoming import or export grid events, plus local Modbus integrations for SolarEdge and KACO inverters. This improves visibility and automation inputs; it does not by itself authorise battery control, prove service compatibility or replace provider rules.
Read source: Home AssistantOfgem's SEG guidance remains the comparison baseline
Ofgem's scheme guidance explains the regulated export framework. Individual supplier rates, stored-energy rules and import-tariff conditions still need checking at the provider source.
Read source: Ofgem