Do You Need DNO Permission for a Home Battery?

Planning permission is the question people ask about a home battery. The answer is usually no, because a battery indoors or in a garage is not a planning matter. The question that actually affects your timeline is a different one: does your network operator need to approve it, and do they need to approve it before the install or after.

That is the grid connection application, and every battery that can push electricity back out to the network needs one. Here is how it works, in plain terms.

Who the DNO is and why they care

Your distribution network operator owns the cables and substation that feed your street. In the North West that is Electricity North West. They are not your supplier, and you do not choose them.

Their interest is simple. The local network was designed to deliver electricity to houses, not to receive it from them. A battery that can export changes the direction of flow on a street, and if enough homes do it without anyone keeping track, voltages drift out of their legal limits. So the industry runs two notification standards, G98 and G99, and which one applies decides whether you can simply get on with the install.

G98: notify afterwards

G98 covers small connections, up to 16A per phase. On a standard single phase domestic supply that works out at roughly 3.68 kW of export capability. Most three phase supplies have a correspondingly higher ceiling, though it is worth having the figure confirmed for your own property rather than assumed.

Under G98 there is no waiting. The system is designed, installed and commissioned, and the DNO is notified afterwards, within 28 days. For a homeowner this is the version you want, because it means the only thing setting the date is the installer’s diary. Most domestic solar and battery systems fall here.

Submissions now go through ENA Connect Direct, the industry portal, which auto approves routine domestic solar, battery and heat pump connections. Your installer handles it. You should not be filling anything in yourself, but you should expect a copy of what was submitted.

G99: approval comes first

Go above the G98 threshold and you are into G99, which reverses the order. The application goes in, the DNO assesses what the local network can take, and the system cannot be energised until they have agreed to it.

The wait varies by operator and by how loaded your local network already is, and some run a fast track route for straightforward domestic cases. Occasionally an application comes back with a condition attached, usually a cap on how much you may export. That is not a reason to abandon the project, but it is the one part of the process nobody can promise a date for, which is why it belongs in the conversation at survey stage.

Export limiting, and why battery size is not the issue

This is the part that surprises people. A 20 kWh battery does not automatically need G99. What the thresholds measure is export capability, not storage capacity, so what matters is the inverter and how it is configured.

Batteries stack from 5 kWh up to 60 kWh, and a large bank of storage sitting behind a 3.68 kW export limit can still be a G98 connection. The limit is set in the inverter and declared on the application. It does not restrict how much you can store, how fast you can charge from a cheap overnight tariff, or how much of your own house the battery can run. It restricts only what leaves the property, which with the Smart Export Guarantee paying around 12p per kWh against 24p grid electricity is the least valuable thing a battery does anyway.

So the sensible design question is not how big a battery you can have. It is what you want it to do, and whether export is worth triggering a longer process for.

What this means for your install

Ask any quote three things: which standard the design falls under, whether the application is in or still to be submitted, and what export limit is declared. A quote that cannot answer those has not been through the step that sets your timeline. The work on site is 2 to 3 days either way.

We use subcontractors for parts of some installs, as is normal in this industry. The application, the design and the handover are ours to manage and ours to answer for, and as an MCS accredited installer the paperwork is part of the job rather than something you chase.

If you would like someone to look at your supply, work out which route your system falls under and tell you plainly what it means for timings, our survey is free and carries no obligation.