DNO and compliance · checked 2026-09-03
G98 home battery UK: DNO notification, limits and paperwork
G98 is not a battery-size label. It is an ENA connection route for fully type-tested micro-generators up to and including 16 A per phase. DNO guidance commonly describes this as up to 3.68 kW per phase. For an applicable single-property installation, SSEN says the installer notifies the DNO with G98 Form B within 28 days after commissioning. If your inverter output, total site generation, number of generators or product paperwork falls outside the route, ask the DNO about prior approval and G99.[15][29][20]
What G98 means
G98 is an Engineering Recommendation used for connecting fully type-tested micro-generators in parallel with a public distribution network. The current ENA catalogue describes G98 as applying up to and including 16 A per phase.[15]
For a battery, the relevant number is usually the AC power that can flow to or from the grid through the inverter, not the storage capacity in kWh. A 10 kWh battery and a 2 kWh battery can still need different connection routes if their inverter outputs and site arrangements differ.
The 3.68 kW figure is about output
Sixteen amps per phase is commonly expressed as about 3.68 kW per phase on a nominal 230 V supply. SSEN describes its G98 process as covering small-scale generation equipment at 3.68 kW or less per phase at one property.[29]
That is a per-phase connection limit, not a promise that any product labelled 3.68 kW can be connected. The DNO will care about the total generation, the inverter certificate, the property and the other equipment already connected.
Notification is not the same as prior approval
SSEN says an applicable installation of up to 3.68 kW per phase at one property can use the G98 process: install compliant equipment, then submit G98 Form B within 28 days of commissioning.[29]
The same DNO page lists situations needing an application before connection, including more than one generator at a property, another nearby installation by the same installer within the last 28 days, or total generation above the G98 limits. Your DNO may present the workflow differently, so use its current form and instructions.[29]
When G99 enters the conversation
The G99 recommendation covers connection of generation equipment in parallel with public distribution networks outside the simple G98 route. The current G99 document also discusses energy storage and connection processes, which is why a battery system cannot be classified from its marketing name alone.[17]
If the battery can export through a grid-connected inverter, ask the installer to state the registered capacity, export limit, type-test evidence and proposed DNO route in writing. If the product only powers appliances from its own sockets, that is a different electrical arrangement, but it still needs safe use under the maker's instructions.
Paperwork to keep
SSEN says the G98 submission needs property details, the proposed total generation capacity and an inverter type-test certificate whose power rating matches the inverter rating on the schematic diagram.[29]
Ask for copies of the final schematic, certificate, commissioning record, notification form and any DNO response. ENA Connect Direct is the network industry's device and application platform, including a place to check generation-device information.[30]
Why G98 is not a marketing badge
A product page may say "plug-in" while the UK installation still requires a dedicated circuit, a qualified electrician or a particular DNO process. Fox ESS's MiniQube page itself says formalised plug-in battery guidance remains limited and refers to existing electrical and grid standards, including G98 where applicable.[25]
The government's 2026 plug-in solar route does not change that. The announcement and interim specification concern plug-in solar microgeneration, not blanket permission for plug-in batteries.[3][4]
A safe G98 buying process
Use this sequence: identify whether the battery connects to home wiring; record the inverter's maximum AC import and export; add every other generator at the property; check the exact model in current ENA or manufacturer paperwork; ask your DNO or accredited installer which route applies; then keep the completed notification or approval documents.
If a seller says "G98 approved" without giving the relevant model, certificate and process, treat the statement as incomplete. The UK plug-in battery rules guide explains the wider distinction between solar approval and battery approval.
Questions people ask
What is G98 for a home battery?
G98 is the ENA route for fully type-tested micro-generators up to and including 16 A per phase. A DNO commonly expresses that as up to about 3.68 kW per phase, but the exact battery inverter and site setup decide the route.[15][29]
Does G98 need prior approval?
For an applicable single-property installation, SSEN says the equipment can be installed and then notified with G98 Form B within 28 days of commissioning. Other setups may need prior approval, so follow your own DNO's process.[29]
Is a battery over 3.68 kWh G99?
Not necessarily. If the total export capacity, number of generators, equipment type or site circumstances fall outside the G98 route, ask the DNO about G99 or another application. Do not choose the route from battery kWh alone.[17][29][20]
Did the plug-in solar rules remove the need for G98?
No. The 2026 plug-in solar specification is for plug-in solar microgeneration. A battery's charging and export path has to be checked under its own UK electrical and network requirements.[3][4]
Sources and further reading
- [3] GOV.UK: Households can save as plug-in solar panels come to marketGovernment plug-in solar announcement and its defined scope
- [4] GOV.UK: Plug-in solar regulatory amendment and interim specificationPlug-in solar interim specification, not a blanket battery approval
- [15] ENA Document Catalogue: current G98 recommendationCurrent ENA catalogue entry describing G98 and 16 A per phase
- [17] ENA Engineering Recommendation G99, Issue 2G99 recommendation and its energy-storage connection context
- [29] SSEN: Installation of up to 3.68 kW per phase at one propertySSEN 3.68 kW per phase, 28-day notification and application conditions
- [20] SSEN: G98/G99 generator requirement documentsSSEN G98 and G99 forms and support documents
- [30] ENA Connect DirectENA platform for generation-device information and applications
- [25] Fox ESS MiniQubeManufacturer's current UK compliance note for a plug-in battery product